| Author | Message | ||
     Miguel A. Garcia Experienced User Username: magarcia Post Number: 46 Registered: 3-2005 |
I am experiencing charge battery problems in ambient temperatures of more than 35ºC. All has started with the installation of new 2 extra electric fans wich drops 15 Amperes when switched on. I have tested the generator working and with motor cold and iddle running (over 1200 or 1500 RPM), it gives 13,60 volts of charge. If i let it run a bit higher (over 2500 or 3000 RPM) it rise to 13,85. These readings has been done with 29º C. and with battery conected. From this, i suspect that the generator ir working right, and the regulator too, at least at this temp. problems comes with higher temp (with more than 35ºC. and after a run, when under bonet is hell temp) Then, i suspect that generator does not work right, or regulator does not. In this scenario, battery drops dramatically in minutes. I have a second new small truck battery in the boot for emergency situations, and this was dropped too, this time, fans were not switched on, so i think that the heat is the problem. Could be that the regulator is not right tunned? I think that the following range of charges is right: 50F (10C) 14.9 to 15.5 volts 68F (20C) 14.7 to 15.3 volts 86F (30C) 14.5 to 15.1 volts 104F (40C) 14.3 to 14.9 volts so, from this reading, mine is giving a lower charge ratio. But i am not sure if this range is with the battery conected or disconected... Any sugestion? Could be a new Lucas RB.340 regulator the solution? Does the new ones come yet calibrated for the Rolls Royce requirements, or their standar settings are right for early shadows? Or would be better (but i do not like too much it) to replace the generator with a new alternator with build-in regulator (as is done in some triumph cars wich mounts from factory same generator and regulator that these early shadows)? Thank you in advance for any help here. I would not like to drop a battery each weekend.. :-P | ||
| William H. Trovinger II Prolific User Username: bill_trovinger Post Number: 220 Registered: 8-2003 |
Miguel, I would think that you are better off changing the alternator out for a new one. This is a normal modification that is even recommended by Albers’ RR/B. The replacement unit is an AC/Delco with the pulley wheel from your old Lucas unit. I am sorry I do not have the Delco part number but someone else on the forum may. Also this eliminates the need for a separate voltage regulator, as the Delco’s is built-in. Additionally, I believe that the cost of the Delco is less than the new Lucas regulator. I think the replacement AC/Delco will cost you around U$100. I can tell you that an exchange on my Delco last year was U$38.88 plus U$15 core charge; my ’76 already had the modification many years before I got it. Best of luck; Bill | ||
| Miguel A. Garcia Experienced User Username: magarcia Post Number: 48 Registered: 3-2005 |
William, Thank you. From your words, i deduct that my problem is a common one to this Dynamo mounting very early shadows.. isn´t it? Well, the Delco alternator you say is: MUD 11964SX ALTERNATOR 11AC DELCO Chassis 1001-7411 ? Is it easily replaced in the place of the dynamo? Thanks again! | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 419 Registered: 9-2004 |
Check your belts are not slipping when hot you should have 14.2 volts with dynamo or altenator. Dynamo should cope if it is working ok with the correct regulator setup with extra electric fans. Dynamo will not last so long as an altenator and will not give the output at lower revs. | ||
| John Kilkenny Unregistered guest Posted From: 60.230.150.160 |
Miguel, The RB340 Regulator used on the early Shadows to control the generator (not alternator)needs the current to be adjusted as well as the voltage.Instructions for doing this are in Section M6 of the Maintenance Manual. However the maximum generator output is 35 amps so if you are loading it with extra equipment it is a good idea to fit the higher output alternator. Regards, John (Message approved by david_gore) | ||
| Miguel A. Garcia Experienced User Username: magarcia Post Number: 49 Registered: 3-2005 |
Patrick, belts do not slips as i checked them at first. I think that it could be neede to adjust the regulator voltage, as John says, but i have unscrewed the 3 screws, and they just take it out from the support. The backelite cover seems to be sealed and i do not know how to open it without breaking it. I do not see any more screw closing it :-( just to plastic rivets intead of 2 screws... I have read the procedure in the workshop manual, and also the one posted in this forums, but i do not know how to open it. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 52 Registered: 3-2005 |
Hello again. I am asking some local dealers for comparing prices with other UK deals (introcar, flying spares, beare essentials, ect..) and with this reference: "AC DELCO 11" , or with the Rolls Royce reference number "MUD 11964SX" , DELCO does not give them any result. Does anyone here has the real DELCO reference, or any other actual alternator or other brand that could be used in the generator to alternator conversion? I suspect that if i find one in a local dealer that fits on SRH3430, the saving will give me for a weekend in the country ;-) | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 420 Registered: 9-2004 |
Miguel, the plastic rivets as you call them have a peg in the centre that pushes out,the plastic connector can then be pushed out from behind collapsing the prongs as you go. The cover can then be removed. Nice to keep the car original with the dynamo as they are getting thin on the ground now. | ||
| Peter Colwell Experienced User Username: peter_colwell Post Number: 11 Registered: 3-2005 |
Generators and alternators each have advantages. The main advantage of generator is that they are virtually indestructible, electrically speaking. Ie. an accidental short circuit will not upset them. Alternator will disappear in puff of expensive smoke. Alternators became popular because their high low-speed charging capacity allowed two thing; a smaller lighter battery to be fitted in increasingly confined space, and more amps-eating accessories to be fitted. In my experience, sometimes strange electrical problems are cured by the simple fitting of a new battery. Even though nothing appears to be lacking from the current battery. Eg. my CD player recently stopped working, with continual error message. With approaching winter I decided to replace the battery early to avoid the obvious anticpated problem. Voilà, the CD player started working perfectly again, untouched. In theory the system voltgage with alternator running should have been normal, and all other systems were working perfectly. But the fact remains that a new battery fixed the problem. It is amazing what mysterious problems in older vehicle may be fixed by a new battery, - and a full tank. Peter | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 53 Registered: 3-2005 |
Hi Peter. Battery fitted is new, and have a new one too for light trucks as emergency in the boot plus 2 Booster Starter fully charged for taking care for starting problems. As you see, if someone have a look into SRH3430 boot could think that i am doing some black market traffic with canned energy :-P. I agree with Patrick, about keeping the car as original as posssible, so for starting i have ordered a new LUCAS RB.340 regulator. I will fit it once i receive it (Now from UK by parcelforce it is taking over 15 days!!!! a foolish for 2 counties in 1:30 hour by plane and in the EU both!!) If after fitted i expercience the same problems, i will go to the alternator conversion. In this matter, i am advancing too asking for prices in local dealers, but as i told before, no delco dealer in Spain can tell me any equivalence for the piece with the RR part number. They told me that has asked to USA main office too, and they could not help them. They ask me for the DELCO reference. This way they could have a cross reference with other manufacturers so they will tel me any equivalent of any brand for it. Has anyone in the forum done the conversion? If so, the reference number stamped in the body or mounts of the new placed alternator would be helpfull!! Also, please, if any of the masters here could open my blind eyes about the causes of these problems with high temps, would be welcome. Why does the efficience of the regulator drops so dramatically with high ambient temps? sorry for my ignorance. I am just a very early novice "one day per month mechanic". Miguel | ||
| Ralph C Brooks Unregistered guest Posted From: 71.105.49.254 |
I made this conversion a year ago with a kit from Albers; 317-873-2360. Not cheap, but R-R approved. The kit included a 108 amp Delco alternator plus (very important) a bracket mod, a wiring kit and an instruction sheet. Installation was smooth except for interference with the AC hoses which required removal of the compressor. Good luck Ralph PS Unless you are an electrical engineer, the wiring kit and instructions are ESSENTIAL. (Message approved by david_gore) | ||
| John Kilkenny Unregistered guest Posted From: 60.230.150.160 |
Miguel, This is probably a silly question but are you sure you have a generator and not an alternator ? From the diagram it looks easy to remove the two screws holding the RB340 cover,whereas I know it is tricky to remove the cover of the 4TR Alternator control unit. Regards, John (Message approved by david_gore) | ||
| William H. Trovinger II Prolific User Username: bill_trovinger Post Number: 221 Registered: 8-2003 |
Ralph; Would you by chance still have the instruction sheet from Albers? The modification was done to mine years before I purchased it and I would like to compare what Albers is recommending versus what was done to mine. Best regards, Bill | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 54 Registered: 3-2005 |
Absolutely our cars are considered as rubish by Rolls Royce Official Workshops and dealers. In Spain, the only one official Rolls-Royce workshop is Royal Crown S.A. wich is too for bentleys, Aston Martin, Maseratti and Ferrari (what a cocktail, eh?). I called them 5 days ago asking if they could afford the conversion from the Dynamo to Alternator for SRH3430. They answered "we will call you in one hour to quote it.." 4 days after, tired of waiting their call, i try again. The answer could not be more surprising: "Sir, sorry. This is not possible to do as we do not know how to do, and there is not documentation about how to do." Of course i told them that some Shadow I fits alternator instead of generator..."Yes? Sure? we do not know how to do that... Is impossible to make this conversion. bye (..and do not call again... may be were the unpronounced words on mind of that man on the phone..)" How alone are we going to feel with this official support!!! | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 55 Registered: 3-2005 |
Ralph, does Albers has website? I am located in Spain. I do not mind to buy from overseas, but i would prefer to get it from UK or any other EU country. Does anybody have any information about where to buy a conversion Kit for it? | ||
| William H. Trovinger II Prolific User Username: bill_trovinger Post Number: 223 Registered: 8-2003 |
I do not know your problem with purchase from the US but here is the website: http://albersrollsbentley.com/ | ||
| John Aravanis Experienced User Username: krug300 Post Number: 21 Registered: 2-2005 |
Hello Miguel, at least your "official" RR/Bentley (etc) dealer called back.....albeit slightly delayed. Here in Greece, at the mention of Silver Shadow I they very politely hang up. Why don't you buy from the U.S.? Take advantage of the 1.26 euro to dollar difference while it still exists! Worse case scenario is that you will be slapped with another 25% for VAT and customs in Spain, so its back where you started from. Regards, John | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 56 Registered: 3-2005 |
I am just browsing Albers website now to order the kit. Thank you all for the help!!! Regards PS: well, i see tha no online orders can be placed, just requesting spares... I had to wait their reply. Thank you all again! | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 798 Registered: 4-2003 |
Watch out, chaps. Only Shadows without aircon have a generator. There were very few of these cars sold. The rest all have alternators and airconditioning. The drive belt and mounting setups are completely different on those two types of car. Don't even imagine that Albers in the USA will have a conversion kit for a very rare and early car not fitted with airconditioning and fitted with a generator. These cars were never sold in the USA. ps: if the electrics won't work properly in the heat, they will never work in the cold weather. Electrics and batteries like hot weather. With the battery in the boot, the setup on a Shadow is ideal to avoid large short-term and excessive swings in temperature. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 58 Registered: 3-2005 |
You are right. In SRH3430 generator is located in the same place where AC compressor is mounted in AC equipped Shadows. Belts are different then. Tonite when arrives home, i will take a picture and upload it so all you see where is located the dynamo. Anyway, i suppose that any alternator that could be placed in the same location that the generator, respecting the actual belt distribution, could do the work... In fact, this operation might have been done many times by any automobile electrician over 50 years age... | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 421 Registered: 9-2004 |
Miguel have had low outputs from charging systems caused many times by faulty earth connection from the RB340 regulator to ground. What part of Spain are you as i am passing through later in the year with RR. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 59 Registered: 3-2005 |
I live in a really nice town called Aranjuez, wich is most known by a music called "Concierto de Aranjuez" and for it´s Royal Palace. This is short from Madrid (50 Km) and from Toledo (40 km). If you go from north coming from France (center area, Paris, Bodeaux, etc..) or UK to Andalusia you will pass in front my door!! Anyway, if you have planned to pass near Madrid, i eill be really glad to meet you (and your family if you travel with them) and to invite you home with me and my family if we agree with the date (summer hollydays could be..)!! let me know by email the calendar of your travel. If you have some time to spent here i will show you all nice places near here (Toledo, El Escorial, El valle de los caidos, Segovia, Chinchon are MUST for any visitor...) Where would you come from? About the Dynamo, here is the pic in zenithal view  Here a view of the belts from right side:  and from the left side now:  | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 799 Registered: 4-2003 |
Phew. Imagine: no aircon in Spain !! You drive past ski lifts on the way around Madrid. 40C in Summer, -10C in winter. I went to a friend's wedding in August a few years back at El Escorial. Quite something else I may say. The service was earlier at 2pm in a steamy Madrid church, and the reception started at 10pm at El Escorial on the clubhouse terrace on the golf course, with a view for 50 miles in the balmy evening. In Spanish style, we 10 from Zurich were lost in the crowd among the 300 guests, and barely spoke to our best mate, the groom. We stayed in Madrid for a week and commuted to the various associated functions. In Toledo, it was 45C, and the ice cream shops made a fortune. I love the temperature indicator roadsigns every 500m in Spanish cities. I still use the kitchen knives I bought in Toledo. We probably drove by your house. I have never understood Spanish names, and how they change after marriage. RT. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 422 Registered: 9-2004 |
Migual that dynamo is genuine RR lucas fitment DO Try To Keep It Original. Going by the pictures i think some of your probs is that you have not got the rad cowling fitted this will make such a diference to the throughput of air flow. RT may be of help on this as he can advise on original fitment or not. Will see if i can find some pictures of my last visit going through Madrid we lost our way in the old part and had a very helpful taxi driver lead us the way out. This was before the sat nav development. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 60 Registered: 3-2005 |
Would be nice to see the pictures of your Madrid´s visit!! Just let me know when you shall come this yeat to arrange a meeting. Contact me by email and i will send you my telephone number. About the cowling of the radiator that you say, is it the cowling shown in the draw below? I had not notice that before you said now!! Would you think it could be the guilty of my temp problems and what i am suffering with low charge? As i have said before, i got this problems of low charge only with the motor HOT and HOT wheather Too!! None of this problems while in winter!  | ||
| William H. Trovinger II Prolific User Username: bill_trovinger Post Number: 225 Registered: 8-2003 |
Hopefully someone can help me understand what is going on here. I have gone back and read this thread from the top and to tell you the truth is doesn’t make sense to me. Miguel, in your first post you quote output rates for your generator at different temperatures. However, the worst rate you quote is 14.3 volts, which is still way above the batteries rating of 12 volts. Granted the system should be putting out more than 12 volts but 14.3 seems to me to still be in the acceptable range. So I guess my question to you is why do you say that the battery is failing? Is it that the car will not start after running on extremely hot days? Or is it that on hot days there is no power to anything such as headlamps? Granted I am know making an large assumption but it sounds like on hot days Miguel is driving his car it heats up and then will not start again, so he boost the battery with a second one and the car starts. Thereby, he is presuming that the battery has gone dead. If my assumptions are correct, I would guess that the trouble is not in the battery, generator nor voltage regulator. Years ago I remember having a similar problem on my ’73 Mustang. This car ran very hot and one summer while working in DC with plus 90% humidity the car would start and run for awhile but then if you turned her off and ran into a store for 5 or 10 minutes she would just click so I assumed battery problem. After having the battery tested and voltage regulator we discovered that the starter was about to go, as the engine and starter heated up something happened. The only way to deal with this was either to let the car sit for several hours to cool back down or boost the battery with a second one. Once the starter was replace problem was gone. If I am misunderstanding Miguel’s problem please excuse this post but if my assumptions are correct I think the starter is worth a look. Best regards, Bill | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 423 Registered: 9-2004 |
I had a 50s Ford Sunliner drophead hydro electric operated roof with 6V battery. great car started every time cold however if stopped to put the roof up or whatever the thing just would not start untill nearly cold. A real let down pulling the birds in my youth. Turned out to be the carb flooding,high float set up. William i took the figures that Migual put up as being the correct variation figures that it should show due to the tempt at correct charging rate[volts] his output was low! | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 61 Registered: 3-2005 |
You are right, Patrick, This range: 50F (10C) 14.9 to 15.5 volts 68F (20C) 14.7 to 15.3 volts 86F (30C) 14.5 to 15.1 volts 104F (40C) 14.3 to 14.9 volts is what i think that might be as the right ones at different temps. In fact, my Dynamo is charging at: (29º C) over 1200 or 1500 RPM:13,60 volts (29º C) over 2500 or 3000 RPM:13,85 volts By comparison, my charge ratio is lower that the recommended, so i think that in hotter temps it will fall under 12 volts, so in this situation. all electric comsuptionm in the car will be gone out from battery, as regulator switch off, or if not, i had not understand at least its functioning... I will measure the charging ratio at high temps and will post it here. ragards Miguel | ||
| Bill Coburn Grand Master Username: bill_coburn Post Number: 448 Registered: 4-2003 |
Miguel I agree with Bill T look at the starter those things are very prone to limpus dickus performance when they get old. Get yourself a new Nippondenso from British Starters.com in the States they are superb and a fraction of the cost of the Factory version. RR used this starter from 1987 on! | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 424 Registered: 9-2004 |
Bill,fitting a new starter whatever type will not cure the starting with a low output [charging rate]with use [long run] Lucas starters are bullet proof for a long long time. why because cars should start without the continuous cranking due to other starting related faults not delt with. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 62 Registered: 3-2005 |
Finally, albersrollsbentley has replied my mail: "...The conversion kits your friend purchased were for cars that already had an alternator from 1977-1984. Sorry, no conversion kit for your car..." Well, i think i must try with the ordered new regulator at firts. If it works, it wiould be fine. At least, the cvar has not a larger output that when went out from factory: No Cd player, no extra beams... just 15 amperes more for the fans. Oh!! I forgot to say that i only drive in the day? so the fans would compensate the amperes eaten by the main lights?. If it fails, i have decided to ask to any auto electricity workshop in any village in the country. These people has been doing conversion from Dynamos to alternators from many years ago, in Land Rovers, Tractors and meny other agricola machinery. Of course i will ask as mandatory to get a work that could be undone with leaving no trace of it!! Anyway, i will read the charging level at hot motor and will post here for your information! | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 800 Registered: 4-2003 |
Actually, Pat, the Nippondenso starter has only one drawback if you can call it that. It will crank the motor over even with a very, very low battery, long after the Lucas has stalled. That's possibly a weakness of the lucas in some respect, but at least it's a safe condition. The drawback is that a Nippondenso also winds the motor long after the voltage is too low to provide a spark. With a low battery, the Nippondenso doesn't even complain, and sounds quite normal. It is easier to burn out a Nippondenso for this reason. The Lucas will simply stall and force you to take proper action. Many an owner of these cars with a Nippondenso is dismayed that the motor cranks but will not start, and are flabergasted that a new battery cures it all. Which reminds me, MG: is your ignition coil's ballast resistor correctly wired to short circuit while starting ? If you have an ignition coil with an internal ballast, expect poor starting due to the long main cable run among other reasons on these cars. RT. ps the voltages quoted are well within range, but the battery is probably due for replacement. Indeed, the charging voltage is designed to be lower at high temperatures. I would either adjust the regulator or leave well alone. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 801 Registered: 4-2003 |
MG: I forget your chassis number. If it is an early RHD 4-speed, BritishStarters.com have just released a Nippondenso starter for SCII, SCIII and 4-speed Shadows (pre-1968 RHD cars). I have the one for all 3-speed cars and all later cars, and it is a brilliant component, carrying a lifetime guarantee. I replaced the original Nippondenso by this one, and it is at least as good as the old one. Bill C. has bought a couple too. RT. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 63 Registered: 3-2005 |
SRH3430. sorry, no time to type, just for reading.... SORRY again. Miguel | ||
| Laurie Fox Experienced User Username: laurie_fox Post Number: 15 Registered: 6-2004 |
Being a MK VI owner I am only an interested spectator in this topic. However, I do have some experience of regulators and how they work. I find it important to know something about the currents flowing at different times in different parts of the circuits as well as the voltages and the 30-0-30 ammeter on B420EY is, in my case, a very useful instrument. Apart from the mention that the electric fans take 15 amp there has been no mention of current so far in this topic. Do Shadows etc. have proper ammeters? | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 802 Registered: 4-2003 |
As I suspected, a rare and desirable early 4-speed RHD (chassis 4482 and earlier). It would be a shame to change the generator, as cars so equipped are extremely rare indeed. I have seen many Shadows, but never one with a generator. I saw a picture of one only once before, maybe 25 years ago, in an RREC publication: it is such a novelty that it deserved print ! RT. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 803 Registered: 4-2003 |
Valid point, Laurie. I have problems to believe that an extra 180W/15A causes difficulties. Like your car, assuming it has the 5" RA5 generator, my R-Type, B174UM, has a nominal 24A-rated generator. That's quite enough to drive at night with the two 100W headlamps and two 100W driving lamps (inserts to replace the Colonial spec twin foglamp beams, and relay interlock to high beam) for any length of time without battery depletion. MG says he only drives daytime with the lighting off, so there should be no problem. That's why the battery is suspect. RT. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 64 Registered: 3-2005 |
Well, i have not at my saw now the car to see exactly the ammeter scale, but from what i remember My Shadow ammeter points "0" (middle of the scale) in normal iddle motor speed in normal temp. If i swich on lights it marks "-5" or first 1/5 from middle to the left, and with fans on, marks "-20" or even more, over 1/2 in the left from the middle. I NEVER has gone plus than "0" or turned to the right side. Running in the road at medium speed, it keeps again to "0", also with lights switched on. If i turn on fans while running in this same conditions, it goes down to the"-5" or first 1/5 from middle to the left . Richard, I did not know i had a such rarity at the garage...happy to know that! In fact i would love to have all information possible about my unit. i asked for the lady at the RRoC in UK, and she kindly tols me that they had the factory sheets, but nut further information about it. Would be possible to get any other kind of information from other source that RRoC Uk? | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 65 Registered: 3-2005 |
After reading your posts, and for being sure about it, I will do tonite what may be should had to be done at firts: replace the battery for the new one. I had not done that before as the one mounted is just 6 months old and the other one i have is a large light truck one that does not fits into the battery bay in the boot. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 66 Registered: 3-2005 |
Richard, the one that SRH3430 has is a LUCAS C48 generator and Lucas regulator RB.340. This gives 25 Amp. | ||
| Laurie Fox Experienced User Username: laurie_fox Post Number: 16 Registered: 6-2004 |
Miguel It sounds to me that the dynamo field is not being energised and that the dynamo is trying to do it`s best with just the residual magnetism. Most regulators contain two relays, one for the cutout and one for the field regulation. They usually have five terminals, marked A, A1, F, D and E. The points on the cutout relay are normally open and close when the dynamo voltage rises to about 13. The closure of these points short circuits the ignition warning lamp which then goes out. The controller relay is different inasmuch as the points are normally closed to energise the dynamo field and they open under various voltage and current conditions to interrupt the field circuit and reduce the dynamo output. If these points do not close or if there is dirt on the contacts then the dynamo field will not be energised. If your regulator is of the kind I have described above then I can help to indentify the cause of the problem. Do you have a copy of the maintenance manual M6 which John Kilkenny referred to a short while ago? Your ammeter should be rising to +20 or so when you first accelerate the engine after firing it up from cold. If not, I think we can find out why. Incidentally, voltage measurements in the field circuit are best done with an analogue voltmeter rather that with a digital voltmeter because the voltage to be measured is not actually steady and an analogue meter in better at giving a correct reading averaged over a short period whereas a digital meter will try and record the peaks and valleys. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 67 Registered: 3-2005 |
Laurie, yes, i have the manual mentioned. I have seen the procedure for testing the regulator, but as is needed to broke some plastic stitchs to open it, i finally has bought a new one (is an exact reproduction, i think). I would not like to start work and if something goes wrong not to have a second chance so i shall not do it before i have the spare one. Really i do not feel myself able about electrics in the car. I feel able for doing many other things, but i am not too sure when speaking about electrics. In fact i tried to open the regulator, and just take out from its support and saw the wires too too short for reconecting them if i take them out, so i decided not to touch them. After reading all the post and all from all you friends your answers, i am more convinced that is a problem in the regulator. I think that new ones comes yet properly tunned for optimal performance into the mentioned range of charging ratios for different temperatures. Also has been very usefull you last reply in wich you say about the ammeter reading about +20. Mine NEVER has read that!!! just "0" or negative values... | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 425 Registered: 9-2004 |
Fitting a new battery is just a stop gap sorry. Lets test the battery in its present state first. Connect a volt meter to the battery and read the live reading 12v hopefully,now with the coil ht lead disconected get someone to crank the engine while you watch the voltmeter reading drop and hold at about 9.5 volts for 10 seconds. If it drops quickly below or you have not 12v's in the first place charge the battery from an external source and then let it stand for an hour or two,then carry out the test again. If you have a amp meter it would be intresting to know what the starter is drawing. This can be done with the type that go over the main + battery lead. If ok then we will go on to testing the dynamo and regulator as you state that it appeares the ampmeter does not go to the + position at all even after start up. Have known the in car amp meter not to function correctly as well. Richard when a Lucas starter is low on power you can still start the car by swinging the starter on the com stroke, try doing that with a Jap jobby. Richard a faulty ballast will play up more cold than hot i thought! | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 426 Registered: 9-2004 |
Laurie,the RB340 is a current control box,This type is called i think a three bobin coil type. 1 cutout relay. 2 voltage regulator. 3 current regulator. Can be set up with out to much trouble from memory. After dynamo test first is a must. | ||
| William H. Trovinger II Prolific User Username: bill_trovinger Post Number: 226 Registered: 8-2003 |
Miguel; RE: your post of 16.06.05 4:22 am Do not be scared of automotive electrical. Biggest thing to remember is to mark all wires, and make diagrams (today digital pictures work better) before disconnecting anything. Another thing that I have found helpful if to print out a very large blow-up of the electrical diagram (too many year in front of these computer screens have done in my eyes), for my ‘76 the print out is about 4 feet by 6 feet (printed it on a plotter) and it hangs on my garage wall. When I got my Shadow I had never touched a Lucas system and was petrified. I had rewired a few American cars over the years but was so scared of this system I did not want to touch it and would just call a friend who was an electrical engineer. Thanks to that friend and the advise of Richard, David and a few more on this site I have been able to fix a few problems and have lost my fear of this system. What I am trying to say is do NOT be scared of the system or the task, take your time think out your moves ahead and document what you do then I am sure you will succeed! Best of luck, Bill | ||
| Bill Coburn Grand Master Username: bill_coburn Post Number: 449 Registered: 4-2003 |
http://au.rrforums.net/cgi-bin/forum/show.pl?tpc=17&post=7370#POST7370 Patrick I agree entirely. But it seems odd that two batteries are required to start the car. Hence my suggestion re the starter. My experience with these Lucas starters is they tend to draw more and more power with less and less crank until there is literally not enough juice getting to the ignition system to give a decent spark! And this experience over I think eight starters ranging from very early to my '84 Spur when I hurled the unit out and fitted a brand new Nippondenso and now the starter almost throws the engine out of the car!! I am also very familiar with dying batties. Many years ago a very dear friend lent me his Hooper bodied Silver Dawn about a '54 model. A beautiful car. He was so proud of the battery which was the original fitted to the car which was then amazingly over 15 years old! 'One thing ' he cautioned me, 'It's a bit hard to start these cold mornings - if you have trouble use the crank handle'. Use it I certainly did as the rotten thing would not start. Eventually I got it to my battery man and he stared at the thing in wonderment. He asked if he could have it as a souvenir!!! New battery and the old girl had a new lease of life. Friend was quite chastened!! | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 427 Registered: 9-2004 |
Bill i think by his postings that the car is not charging at all. Miguals battery is only months old. I personaly have not had a NEW faulty battery for years and years of many fitted. I think he needed extra batts for starting after useing the car with the extra drain useing the electric fan on hot runs. Lets start with the testing of the system,first batt then the dynamo then the reg then the results will point to the cause of watever and there can be many. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 805 Registered: 4-2003 |
Let's go back to the start. The general assumption of most participants has been, I suggest, that the voltage and current regulators had been adjusted as required during routine servicing. The symptoms suggest otherwise. You should see at least a 25A charging current just after starting with an almost fully-charged battery, and it should settle in time to maybe 3-5A continuous. It sounds as if the battery and charging system here is in good shape, but out of adjustment. The voltage regulator of most cars with generators, including this one, is an electro-mechanical device. It is sensitive, and needs regular adjustment. Settings depend on how new the brushes are, the individual generator characteristics, and the regulator itself. No two applications are identical, and even without any defect they do need setting periodically. A new regulator needs adjusting on the vehicle just as much as an old one does: it is not a plug-and-play module. If you bolt on a new regulator without adjusting it correctly, disaster is a certainty. The early Shadow generators are limited to 36A, plenty for these cars. To adjust the voltage regulator contacts, you simply remove the cover and put some paper between the cutout contacts and measure the voltage at the armature. I have no records for a Shadow generator as they are very rare, but for example on the R-Type it is as follows. You need a voltmeter with a needle: digital ones are useless here. Start the motor and increase the RPM until the needle starts to flicker. On the R-Type, this is around 16.2V depending on ambient temperature, and I suspect that the early Shadow generator setting is similar or slightly lower. Adjust the flicker point to specification. Afterwards, of course remove the paper and refit the cover. The temperatures and corresponding voltage figures are in your workshop manual. If the regulator has not been adjusted in the past 2 years, then this thread has been in vain. RT. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 428 Registered: 9-2004 |
Hang on Richard Battery first then i would do the output of the dynamo, then do current on load setting to the maximum rated output of the dynamo. But ofcourse much else. we don't want the solder melting on the com. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 806 Registered: 4-2003 |
Pat, That's a fine point, but the generator voltage needs regular setting anyhow. No doubt, a battery test will only show that the battery is low on charge, but that's useless information until the charging system is calibrated properly. The voltage regulator is set with the battery out of circuit (cutout relay blocked by a piece of paper). The voltage setting is independent of battery condition. If the battery is so new, I would simply do that first and see if it solves the issues. After all, the battery sounds to have at least some charge. Then, test the current limit by turning everything on (headlamps, blower, radiator fans etc) and set it to 36A, again independent of battery condition. I would never put in a new battery without first doing that. Battery condition does not affect the charging system; rather the reverse. Especially with the specified out-of-circuit adjustment used on these cars, the regulator is the first thing to check before brushes and batteries, although the generator does need regular servicing too. Gone are the days of topping up batteries with distilled water. I would verify the charging system before chasing shadows (or Shadows!). RT. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 429 Registered: 9-2004 |
Richard. I would do a test on the dynamo after first the battery as stated then if all ok last test the RB340 current regulator not a voltage regulator. Then correct as nessesary finding other poss faults ie bad connections etc on the way. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 807 Registered: 4-2003 |
Hey, Pat, the regulator features both a voltage regulator and a current limit regulator. If you look at the field modulator solenoid in the regulator, you will see that it has a fine inner winding for voltage regulation with hundreds of turns, and a very thick outer winding with only a few turns, for current limiting. RT. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 430 Registered: 9-2004 |
Yes but the current is priority first the rest is after as i said in previous post don't want to melt the solder on the comutator. First battery test then we will follow through,we are now way to far ahead missing other important checks on the way first things first. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 808 Registered: 4-2003 |
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| Richard Treacy Grand Master Username: richard_treacy Post Number: 809 Registered: 4-2003 |
I don't want an argument but... The current limit regulator function practically never operates. Only on a very heavy load should the current limit switch in to protect the system. If the voltage regulator is incorrectly set, the current regulator will be incorrectly set too as the voltage setting affects the current limit setting. The no-load voltage setting is, by definition, independent of the current limit setting. The voltage regulator must therefore always be set first with the battery out of circuit as described. Only then can the current limit be set also as described. As for the battery, you had best be sure that the charging is alright before addressing it. Besides, if it recovers with the charging set correctly, external charging and cycle testing is a waste of time. Let's face it, this car is driving around showing a discharge, so London to a brick the regulator needs adjusting unless the generator brushes are badly worn. If new brushes are fitted, the regulator needs adjusting anyhow. A bad battery will not cause the discharge when driving. RT. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 68 Registered: 3-2005 |
Hi again. Today when arrived home, got happily a box from UK. Yes!! the new regulator. so i hahev started the job. After disconectin battery I replaced the old one with the new one, wiring EXACTLY as was before. reconected the battery and started up the engine. Oh! the ammeter pointed EXACTLY as before, but the RED LIGHT on the facia (the one that lights when the cut out in the regulator closes i think, is ok?). Ok, i will review what i have done: disconect again the battery, disconect the wires and reconect tightly again the wiring of the new regulator. Reconect the battery again, and start up again the engine: RED LIGHT AGAIN!!! With my old regulator, red light was turned on just with iddle very low or at very high temp, when parking the car in my garange for example, but only in this situations. I have replaced again the old regulator and the light does not light all the time as with the new regulator. It lights only in the same situations that i had explained before. Confused by this, i have applied the voltimeter (a digital one, sorry) directly to the 2 output cables that i see going out from the dynamo, and it was 5,45 volts in the voltimeter!!!. I thought i was doing something bad, so i went to the boot and applied the voltmeter to the battery: 12,53 continously, as a clock!!, i switched on the fans and the lights: 11,83 in the volt now, if i gives more RPM to the engine, ir raise to 12,2 in the battery always i mean. Till what i understand here, when dynamo turns highly, the battery charge raises, but how is possible to get a so lw reading in the output dynamo? I am confused. Does it shows finally that the dynamo is faulty? How to mind the red light matter with the new regulator? Of course that i think it would be work nicely.. but, could it be faulty? | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 431 Registered: 9-2004 |
Ok Migual,Back to my early postings of procedure. first test the battery and from what you have said it is ok. Forget the RB340 new battery starter and any other try this and that. Next go the dynamo remove the large[dynamo output] and small[field current] wires, connect both wires together with a small piece of wire. Connect the two wires to the + terminal of a moveing voltmeter. with the -wire of the voltmeter connect to a good earthing point. Start and run the engine at idle and increase the dynamo speed to about 1200rpm if all is ok the volts should clime quickly but do not go more than say 16.5 volts at this stage. Let me know the results if any? | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 433 Registered: 9-2004 |
Migual whoops! my posting was not that clear on the joining of the wires,these are two made up that join the two terminals on the dynamo together. The "f" and the "d" wires can be disconected on the regulator and joined together and be tested as above but if no volts are found testing it does not alway mean the dynamo is at fault. The wires can have a break in them etc. Go back to the the dynamo removing the two wires and joining the two terminals,then connect the voltmeter and test the dynamo output as in my previous posting above. Can put a picture up of the test setup later. Let me know if that would help. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 434 Registered: 9-2004 |
Picture of the two wires red and green joined together from the dynamo terminals. the red lead clip from the voltmeter is connected to these and the black lead is to a good earth. start engine to fast idle and check the volts.   If Ok we then will do some continuity tests to the reg next. | ||
| David Gore Moderator Username: david_gore Post Number: 478 Registered: 4-2003 |
Hi Pat, Thanks for "taking Miguel under your wing" so to speak and walking him through the diagnostics. I am also benefiting from this as it is refreshing things I haven't done since my teenage years. Thanks for saving me having to do this from my archives as I have other demands on my time that have to be given priority. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 69 Registered: 3-2005 |
Sorry for the dalay in replying, but i had problems accesing the forums.   here are the pictures of the test. It seem that i have a death dynamo, what do you think? Yesterday battery was gone again, also the replacment one that i have. as the fans were not energysed to run, hot was so high, that after stoped, a hose was broken. :-( furtunatelly the bride was yet at the church and i had enough time to get the motor colder and repair, as the broken was really close to the clip on the side.. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 70 Registered: 3-2005 |
I have to sincerely thank to all of you your help and support. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 435 Registered: 9-2004 |
Migual, just to make sure you did the test as stated,on connection the two gen dynamo teminals are joined together then the + red voltmeter lead attatched, with the other black- voltmeter lead to a good earth and then the motor engine run at a fast idle. If you have done that and your meter is reading as shown then the dynamo brushes are caput or stuck or the com has had it. Remove the dynamo unit. Sorry i to could not access the site till now. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 436 Registered: 9-2004 |
regarding the hot running you may be able to run without the electric fans if a rad cowl is fitted also the fan blade may be upgraded,not sure on that but Bill Colburn may be able to help on that one. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 71 Registered: 3-2005 |
Patrick, yes, the test was done following your instructions. Do you think that with the cowling in the rad, cooling shall be more efficient?. I have found a rad cowling in a reciclying yard in UK, but shippment is more than it costs (75 UK Pounds shippment and 35 UK Pounds the cowling) , so i am looking for other prices... The fan blade is possible to bw upgraded? more air flow ones are available for Shadows? About the Dynamo, i am seriously thinking the possibility of converting to Alternator. Thank you again all of you for the support and help. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 437 Registered: 9-2004 |
Migual,i have enlarged your pic. If you undo the screw holding the cover round the dynamo the plate can be slid forward,then you can see if the brushes are worn down and if the commutator is ok. Not a hard job to fit new brushes if needed. Then all there is if the wireing is ok is to check and maybe set the regulator. Shame to fit a Alternator at this stage. | ||
| John Kikenny Unregistered guest Posted From: 60.230.150.160 |
The correspondence on this issue (59 so far) has reminded me of the old adage regarding cooks and broth. Another old adage worth noting is, when in doubt read the manual. The first sentence of Section M6 of the manual,which Miguel has, is "If the control unit is suspected of being faulty, carry out the following tests and checks before fitting a replacement unit." What follows is a step by step procedure on how to do it. Of course anyone not conversant with electrical circuitry is reluctant to delve into the innards of control units so the best solution is to take the car to the nearest auto electrician who will have the equipment to quickly diagnose the problem and suggest a solution. A good auto electrician will also be able to replace the generator with an alternator without the need for a special kit. On the subject of replacing the generator, while it is nice to keep cars original, Miguel has already loaded his electrical system with an extra 15 amps which is a big percentage of his existing generator's 35 amps. Alternators are much superior to generators ; they give a higher output at low speed; they run cooler; and because the field winding rotates, the much high ouput current is not taken out through brushes which wear. My car (SRH1405) which is an early model has an alternator because it is air-conditioned; I have had it for 22 years and the alternator has not been touched in that time. (Message approved by david_gore) | ||
| John Kilkenny Unregistered guest Posted From: 60.230.150.160 |
NOY FOR POSTING David, I can understand your being reluctant to post my last message but most of the advice being posted is obviously confusing Miguel. He has already un-necessarily bought a new control unit for what is a large percentage of the cost of an alternator and is still being advised to keep the generator. He has the documentation to investigate the problem but does not have the electrical experience to follow it. His 35 amp generator will not keep up with headlights and his two additional cooling fans and also adds to the underbonnet heating. Before he starts spending more money on kits and equipment you would be doing him a big favour by suggesting he takes his car to an auto electrician. It's ironic that the same people who are telling him to keep an inefficient and outmoded generator are the same ones who cheerfully fit modern starter motors to their cars. After saying all that, I enjoy the forum. Regards, Moderator's Comment: Hi John, sorry that you have misunderstood the reason why your post did not appear immediately - this is simply the result of the fact that I have not accessed the forum until now and both messages were waiting for release. We encourage robust discussion and expect strong differences of opinion from our contributors - most users will be aware that I am extremely reluctant to censor/delete posts and this has caused problems for me in the past - needless to say, we all learn from well-argued points of view and I am the first to admit that I have been known to change my opinion after someone has presented a logical point of view that was more valid than my own. Even if I personally disagree with an opinion being genuinely expressed by a contributor; I will always post it for others to comment on - the only time my editing privilege is exercised is where the opinion is malicious or reckless and there will be an explanation why the editing was undertaken. (Message approved by david_gore) (Message edited by david_gore on June 19, 2005) | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 438 Registered: 9-2004 |
John. First read my posts again, you will see that i had said proceedure first not fitting battery, starter,regulator etc. As for the dynamo [generater]it will more than cope when the electric fan is not needed once the cooling is sorted re cowl etc hopefully. And it is as others and i have stated a rare fitment for a RR. Are you saying keep the overheating fault and run electric fans,i think not. Fitting a new dynamo it can be repaired by most folk if they are willing to have a go and help from this forum. Brushes cost a pittance. I have been surprised beyond belief of the jobs carried out by non professionals with the help of forum members. Well i just could not stop without your remark about extra fans add to underbonnet heating. Please explain more as i am always ready to learn with a question or two. Some true owner enthusiasts just love to do the jobs and tinker with thier cars themselves, some others like to be checkbook charlies and swank about in them. That is up to the owner what wish to do. As for Migual he is doing his best and i am sure he will get there in the end with correct help from whoever. A discussion and help is what a forum is all about. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 439 Registered: 9-2004 |
John reading your post of 13th june 11-33pm. Looks easy removing the regulator cover two screws. Well the type what Miguel has,are fitted with as he said plastic rivets. Picture top right shows the white centre peg that is pushed out so as to remove the ponged rivets [two] so the cover can be removed.  Sorry about the dust electrical fields attract. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 440 Registered: 9-2004 |
John K, you could register then your postings would come up straight away! | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 72 Registered: 3-2005 |
Hi, after reading the last posts here, i have to say that i feel that in the spirit of owning classics (it does not mind if they are RR, Mercedes, Lancia or a SEAT) is the privilege of keeping hands on their historic pieces and at least try to understand their functioning and working. Nothig better for this that trying to documents about them as far as possible and trying to solve this light problems. Of course that depending of the nechanical knowledge and experience level, at soon or late, you will find to be stopped at some unsoluble problem by yourself. In this matter wich we dicuss here, it seems that due to my inexperience it has been so soon. Anyway i have to say that i have too present in mind that before doing something that could be fatal fot the car, i will go to the specialist workshop. But this does not mind that me or anyone who has the same or similar doubths, tries to take the knowledge for understanding what is happening. I think that this is the spirit of any technical forum: Sharing experiences and knowledge, and for this matter we speak about, i have to say that IS HAS BEEN very helpfull. I have had too many bad experiences with some self called specialists in some workshops here in Madrid, who takes advantages when billing their work about the unknowledge of the cars owner. Thats way, at least i think that any classic owner is obligated to know as large as possible about his car. Once you have the knowledgs, you can choose about to pay a professional, or to do it your self. About the economical cost of both operations, i had to say that in most cases the difference will be irrelevant, or in some situations could higher if you do it yourself, but also is the satisfaction of a work done by oneself. Finally I will carry the car to an electrician workshop and install an alternator with built-in regulator. This was the last chance i had, but after having in one hand the 1st option: 1-check out the dynamo, go with it to the speciallist, change brushes and any worn pieced. 2- once repaired to fit again, and after if it does not work to change regulator, and at least it could be not be enough amp. outgoing... I choosed the 2cond option: 1-go with the car to the speciallist. 2-ask for the final price of his work 3-if i like it, let him to do it, if not, asking another speciallist. I feel that final price of both options would be too too close, if not cheaper the second one... But at least, as i said before, i will know about what the speciallist is talking about and will not let him to cheat me. Any time after dynamo could go back to the car if needed, as i will not trouhg to the dustbin. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 811 Registered: 4-2003 |
For John Kikenny, Sure, a 20HP would benefit from fuel injection. The trouble is, it's a bit in-your-face. So would be an alternator on a non-aircon Shadow every time you open the bonnet. True, the very rare and collectable Silver Shadows with a generator would benefit marginally from a one-off alternator conversion for sure. However, is not at least a little battery-regulator-generator testing and adjusting worthwhile before going ape and throwing the whole kit away and starting new problems ?? The testing and adjusting of this very simple equipment can hardly be called a specialist job, and takes next to no time. Cripes, the generators have been ultra-reliable for almost 40 years on those cars already, so what's the problem ? How many 20HPs sport an alternator by the way ? If all else fails read the instructions. The Rolls-Royce workshop manual is very clear and correct on the setup procedure in this section. Sorry, but in this case even that has not been done. The suggestions on this site are largely made on the assumption that the base procedures in the manuals are taken for granted as a starting point, and shortcuts (eg instead of "with the motor removed from the vehicle") or refinements are offered. As for the Philistines who go fitting a more so-called modern starter motor replacement on a Silver Shadow, a component you cannot even see without trying really hard, that is the instruction of a factory bulletin over 15 years ago when replacement Lucas starters were discontinued. There's nothing wrong with the Lucas unit, but it's only available aftermarket nowadays. RT. | ||
| Phil Black Unregistered guest Posted From: 210.50.44.76 |
My cars (SRH2281 got the air conditioning in it too and the alternater just like Mr. Kilkennys car and every elec repairman I speak to said they beat the old gennys every time which must be why the factory put them in and now still do like all other car makers some who started them in America even in 1961 Olds and Ponties I think from memory. I just put in a moden starter thats a Nipondenso type and its lighter draws not as much current like before and turns my engine over like a flash so why does that mean Im a Phillistine just because it was cheaper to buy and if I dont have R.R fan belts or Feroado or R.R dealer brake pads that you cant really see either or even big dollar Avon tires from England does that mean I am even worse again. I read other info. that contra outs the first being like dont block up the drainholes on the side of the engine block but Ok and no worries to block off holes in the diff side trunnions which must be there for areason just like the alternators are (Message approved by david_gore) | ||
| John Kilkenny Unregistered guest Posted From: 60.230.150.160 |
First of all David, let me apologise for my mis-understanding. Next regarding Patrick's comments, I did not suggest that fans would increase the underbonnet temperature . I said that the higher operating temperature of a generator would add some heat (though probably minimal). And my comment about taking the cover off the RB340 control unit came from reading the manual which states "remove the two screws securing the control box cover in position". The photo of the cover in the manual is different to your photo. With regard to the value of keeping cars original I believe that where Rolls Royce have made a modification to improve performance there is nothing wrong in retrofitting older cars, particularly if the original component has failed. An efficiently operating car is preferable to a museum exhibit. I don't know how many of our cars still have generators ; according to a book I have, alternators replaced generators in July 1968 but air conditioning wasn't standard until November 1969 although most cars probably had it. I agree with Patrick's comments about the enjoyment of working on our cars, I have obtained great enjoyment over the years doing exactly that. However most of us don't make our living that way, and sometimes don't have the expertise or equipment to do a proper repair job. Apart from major mechanical items this often applies to electrical faults which are often not easily diagnosed. The forum was providing useful suggestions but it was apparent that Miguel was having some difficulty with the circuitry though trying hard. In this case it is far better to have an expert diagnose the problem and suggest a solution, particularly as the diagnosis will normally take only a few minutes. It is very likely a solution will see the generator retained though with an extra 15 amps load it's future is debatable. It would certainly have been preferable to fix the overheating problem, probably with a cowling and radiator cleanout. I have just read Richard's response to my post ; I don't believe Rolls Royce has fitted 20HP cars with fuel injection so I don't see the connection. My car is considerably older than Miguel's but has an alternator. Regards, John (Message approved by david_gore) | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 812 Registered: 4-2003 |
John K: the car with a generator I saw was shown years ago in Flying Lady, and I recall it is a 1971 car. Just for fun, I looked up the spares book, and it lists generators right up until chassis 14896 ! Heavens, that was in 1973. That any Silver Shadow was ever built with a generator beats me, when alternators are clearly more effective. Especially at idle, unlike a generator, an alternator even charge the battery, and the slip ring brushes are low duty unlike the commutator brushes of a generator or starter motor. On what to modify: it's your own choice entirely of course, and I for one would not argue against most modifications even if my opinion is against. It's foolish to ridule someone's desire to modify or not. Almost anything old can be replaced by an improved modern device on a fnctionality basis you may agree. The refernce to 20HP was just that: it would run far better functionally with modern fuel injection, or even a modern motor, but who would dream of that ? The quaintness of a generator these days, to me anyhow, is worthy of at least a straughtforward test and adjustment before being transplanted by an alternator. After all, the smaller 24A RA.5 generator in my R-Type has never let me down, and with far more frontal lighting alone compared to a SS, it does a stirling job. RT. | ||
| Bill Coburn Grand Master Username: bill_coburn Post Number: 452 Registered: 4-2003 |
Actually Richard you have picked a scab off one of my old worries with the Bentley S2. The old C48 generator for which parts are not easy to obtain, must have been working hard to look after the Factory air with the big old piston compressor and a few extra solenoids. Buy I too would like to put some extra fans in and really wonder whether the gen would handle it. I really would not like the appearance of an alternator however efficient - a bit like the appearance of the fuel injection on the 20 HP! | ||
| John Kilkenny Unregistered guest Posted From: 60.230.150.160 |
Richard, I agree with your comments, a generator working within its limitations is fine, and provided any repair costs are reasonable and infrequent there is no reason to get rid of it. However if an expensive repair or replacement is required I would go for an alternator. For the same reason I don't anticipate replacing my original starter motor. Incidently remanufactured G48 generators are available from Star Auto Electric in California for $200. Regards, (Message approved by david_gore) | ||
| Phil Black Unregistered guest Posted From: 203.134.172.198 |
My mechanic has worked on a lot of different cars and has fitted moden alternaters to some of them and he somehow paints them powder black so they dont stand out very much so maybe this could work out OK in Rolls cars too without anybody really noticing it and I think this is what I will do too when I can afford it. He also put a smaller Air conitioning compressor in a Shadow I saw and he did that black too and because it was smaller you hardly saw it at all like the alternater (Message approved by david_gore) | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 73 Registered: 3-2005 |
Hi again. Brushes are bad. Now the problem is that here in Spain, seems to be asking something done in Mars...I do not find them. Does any of you knows where to order them from USA or UK? Thanks again! | ||
| Robert Wort Grand Master Username: robert_wort Post Number: 215 Registered: 12-2004 |
Hi Miguel, Click on the link below and scroll down to Rolls-Royce. This firm has remanufactured Generators for your model. Hope this helps. Rob http://www.starautoelectric.com/ct_CGgenerator.htm | ||
| Larry Halpert Prolific User Username: larry_halpert Post Number: 78 Registered: 9-2003 |
Actually, Star Auto Electric has them for $274.99 US PLUS a $200 core charge, plus shipping to Spain. Over $474US until the old one is mailed from Spain to California to cover the core charge. No auto-electric guys in Spain to do a simple generator rebuild? Larry | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 814 Registered: 4-2003 |
I forget the part number and don't have any here, but those brushes are used on many, many commercial vehicles. My local autoelectrician stocks them for around EUR6 a pair. Try an autoelectrician who does trucks: take an old one as a sample. Otherwise, have Star, or even Introcar, mail you a few pairs. They are cheap components and cost very little to ship. ps Introcar is obliged to charge you the UK VAT as you are in the EU. If the others do not, they will eventually be caught and fined heavily. Only destinations outside the EU are exempt from VAT for sales from within the EU. | ||
| Robert Wort Grand Master Username: robert_wort Post Number: 216 Registered: 12-2004 |
Wow! That's expensive. I found that on Google by the way. There must be someone on the Iberian Peninsular that can help Miguel. Mind you,Miguel, have a search around for Lucas generators in general around some wreckers yards. You may find some brushes that fit. It would'nt be the first time. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 441 Registered: 9-2004 |
Miguel,before you order new brushes do check the commutator where the copper wire joins the armature segments, this is to check that the solder on any of the joins are not melted by some other underlying faults,If it has get new dynamo. If ok more tests after the new brushes are fitted before fitting unit to car. To complete a few more tests when fitted. Not 100% happy with the warning light comments on earlier posting. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 74 Registered: 3-2005 |
Hi all again. After searching here and asking everyone in Madrid, no one has these brushes (in fact, many of them, just has nothing for dynamos!!). Finally, in a very small and old spares shop in the old town side of Madrid, i found and old man who made them for me. I gave him an old one as sample, and next day (today) i went back for it and the new ones. Not expensive: 6 Euros. After placing the new ones (firstly i cleaned the copper and all the joints as explained in the workshop), i remounted again the dynamo, mounted my new Lucas regulator, reconected the battery, and started up the engine: OHHHH.... RED LIGHT AGAIN!!! I applied the voltimeter again to the dynamo, and the read i got was : 0.85 Volts. I have asked to Introcar: they have reconditioned generators for 275 UK Pounds, but in exchange basis, so i had to add over 150 Euros more for shipping my old one from Spain to UK. That would be over 600 Euros. Is too expensive. So, unhappily i have yet decided to mount a 45 or 50 Amperes alternator and leave the old dynamo as decoration in my garage. This was just my last chance, but really i want a usable car, and really this modification, as it is an important one, and when opening bonet will bright the new alternator as an strange thing into the motor bay (i will paint it with mate black painture...), I think it is one is a necessary and excuseable and mainly justified modification. Here in Spain, most english classic cars (mostly jags, triumph, MG, minis, Morris, land Rovers), and not only english, as also Mercedes 180 and 190 from 50´s and 60´s, Seat 1500, Seat 124, 1800, Seat 600, Renault Gordini, etc, had suffered this modification from last 80´s when dynamos spares started to be difficult to find, ans also by the very very bad fame that LUCAS components have here...but mostly this masive modification was done in last 80´s and 90´s. In fact, is very unfrecuent to find in any meeting here any car that was generator equipped from factopry with it on it. All has been replaced with more reliable, powerfull and easy to find alternators. Sorry all for this long term here about this problem i had. Once i have the alternator mounted, i will put here some pictures of how does it fit and shows itself under the bonnet for all you to check it and express your oppinions. Thank you all for the very usefull help and support bringed here. regards, Miguel | ||
| David Gore Moderator Username: david_gore Post Number: 480 Registered: 4-2003 |
Hi Miguel, Just a thought - before you resort to drastic surgery; why don't you contact Pat or Richard and arrange to freight your generator/dynamo to them - they could pass it on to a suitable repairer to quote for the necessary repairs and you could pay the repairer direct by credit card and they could freight the unit back to you. I suspect surface freight within the EU would not be too expensive. Kind regards David | ||
| John Aravanis Experienced User Username: krug300 Post Number: 22 Registered: 2-2005 |
Hello Miguel, if you will have your dynamo on the shelf anyway, you can ship it to me in Athens and I will give it to a good friend who is an "old" car electrician. I was in his warehouse today and he seems to have hundreds of old dynamos and starters. I am almost sure that it can be reconditioned. No charge for the repairs. Best regards, John Athens, Greece} | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 75 Registered: 3-2005 |
John, sure. I send you a private message for you to send me your adress where to send it. Thank you! | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 815 Registered: 4-2003 |
Miguel, You are forgeting something, and it's the oldest trick in the book. Before you do any more component removing or repairing, please read the following. It's no good simply bunging in a new set of brushes and praying Eastwards. Whenever you fit new brushes, the generator normally will not work at first. The brushes need to bed in with a decent current load before the red lamp will go out by itself. There will be insufficient residual field to wake it up and get current flowing across the new brush-commutator interface by itself. This is especially the case with custom-made brushes like yours, or generic ones not precision machine contoured to the exact commutator diameter. Unchecked, the condition may last for several hours of running. Don't worry, it's easy to sort it out. The best way to "kick start" the brushes is to remove the regulator cover, and, with the motor idling, simply press the cutout solenoid to energise the field. This should only be required once. While the cover is off, adjust the voltage and current regulators as described earlier. This adjustment is required every few years and whenever the brushes are renewed. RT. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 817 Registered: 4-2003 |
ps: new brushes are often a problem at first on a DC machine. In industry on DC machines, new and old, large and small, on commissioning we always routinely deglaze the commutator and bed in the brushes at the same time using special sticks of soft pumice stone, pressing them onto the com by hand. It's unlikely that there is enough room to do this on yours, but I assume that you deglazed the com and cleaned out the slots between the com bars when replacing the brushes and before repacking the bearings with high temperature grease. This is all particularly important on unloaded constantly running motors and generators, as long periods running with only low currents (battery fully charged for example) cause glazing and poor commutation. Motors run only occasionally but on rated load (starter, windows etc) are much less of a problem in the commutation area. RT. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 821 Registered: 4-2003 |
By the way, you can buy a brand new Lucas RB340 regulator for £27.50, for example at Bernard Bryant Classic Spares in the UK. Introcar has a nice margin on these !! As many industrial vehicles and farm equipmet (eg Massey-Ferguson) use them, they are not hard to find. Likewise brushes. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 822 Registered: 4-2003 |
I even found new RB340s at £19 from Vintage Supplies Ltd. in the UK | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 823 Registered: 4-2003 |
Brushes £3.50 if you order today: http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=9903&item=7981864503 This site is recurrent. I'm sure you can order Lucas C45P brushes over the counter anyhow as they are so common. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 76 Registered: 3-2005 |
Richard, i polarized the dynamo when new brushes were fitted. I did as you described. It did not work. Also i fitted a new RB340 regulator that i bought for 35 UK Pounds (expensive.. YES, and most for having it just for ornamental purposes...)but none of this worked. Today i got yet the alternator conversion done. It has been used a 50 Amperes reconditioned alternator with built-in regulator. I do not know from wich car does it comes, as i just choosed the one that better fitted on the needed place wher it had to be placed: I mean the holes for screwing and all that folk. It has been fixed as near as the dynamo´s original possition, and the pulley from the lucas dynamo was taken off and fitted in the alternator in susbtitution of its original. Now, alternator gives the neede charge ratio in all moments (well, not exactly, as in continous town driving with a lot of stops and iddle motor, it gives no charge as red light goes on...but just to kick a milimeter the accelerator, it brigs power charge..) As i told all you before, this is not the solution i liked, but it works. Once finished, it was BRIGHTING on yhe bay as a star in the night, but i have painted it and now is more discret. here you can see it:   | ||
| Kilkenny Unregistered guest Posted From: 60.230.150.160 |
Richard, If you look at the history of this problem, initially the warning lamp was not coming on, which signifies that the generator was producing a voltage high enough to extinguish the lamp but perhaps not high enough to provide a useful charge. Miguel also says the "battery drops in minutes" which I don't understand. Miguel measured the generator voltage at 13.85 at 2500 RPM (June 15). I suspect he still had the battery in which indicates there was some charge. Ammeter has never read over 0 but moves from -5 to 0 when running with lights on (June 16) again suggesting some charge. New RB340 fitted (June 17) after which warning light always on suggesting the new RB340 faulty or maladjusted. Original RB340 put back. New brushes fitted (June 23) BUT ALSO NEW RB340 so it is not surprising that warning light is still on. While new brushes take a while to bed in and provide full current they should allow field build up unless there is a large output load. I still don't know if an auto electrician has looked at the problem but I would love to get my hands on it !! I would like to attach a simplified diagram of the RB340 but due to my lowly status (under review) I can't. Regards, John (Message approved by david_gore) | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 827 Registered: 4-2003 |
John K, I share your thoughts. It is always unwise to create a problem, then try to solve another before rectifying the newly created problem. The less said of the methods undertaken in this case the better. Here is a simplified diagram of the RB340 3-solenoid regulator system as applied to early Shadows. The RB106 2-solenoid regulator, as fitted to MkVI etc, is similar, but has two windings on the one regulator solenoid (one for current limit and the other for voltage control), and thus only one field control resistor (badly called the shunt) contact. These are such simple systems, parts are cheap and easy to buy, and I'll bet the old RB340 simply needed its routine adjustment. Heavens, they are fitted to everything from Austin Healeys to farmyard tractors after all, and any autoelectrician should know them backwards. Oh well. RT.  | ||
| John Kilkenny Yet to post message Username: john_kilkenny Post Number: 1 Registered: 6-2005 |
Richard, Thanks for the diagram. I believe the RB340 is a little more sophisticated than your diagram suggests. If you look at the diagram from the manual that you posted on June 17 you will see that the cut out relay has two windings in series. Though I haven't looked at a RB340 I imagine the top winding is low impedance to take the generator output current while the lower one is higher impedance to hold the relay on. The output and the reference for the voltage regulator relay is taken from the mid point. I think the reason for this arrangement is to prevent the battery from discharging through the generator at low revs ; as soon as this starts to happen the reverse current through the low impedance winding will oppose the holding winding and drop the relay. If this wasn't done the battery would hold the cut out relay on. I notice that Miguel mentions that his warning light comes on at idle, this shouldn't happen with an alternator and suggests that he needs a smaller pulley. Regards, John  | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 831 Registered: 4-2003 |
Yes, John, You are correct. I made my diagram as simple as possible, with the key components all labelled. It is a functional schematic, and not a detailed one showing all the fruit salad (condensers, additional winding tappings, ignition lamp, ammeter shunt etc.). These regulators are a universal type intended for as many applications as possible. They feature several components, tappings and functions very rarely utilised by the vehicle designers. You mention the cutout. A few times I have deleted it, fitted a 60A power diode in its place, and tuned the open loop voltage to be 0.7V higher at the D terminal. One minor detail: you show the generator fields in parallel, whereas I am fairly sure that they are in series. Also, you have shown the indicator lamp in the wrong place. It should go from the ignition switch to D. The ignition switch, of course, electrically connects directly to the battery at all times. The way it is shown, the ignition switch and lamp are simply transposed. RT. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 832 Registered: 4-2003 |
Actually, the warning lamp is between the W terminal and the ignition switch on some cars, and between the D terminal and the ignition switch on others. Functionally there is no difference of course. RT. | ||
| Miguel A. Garcia Frequent User Username: magarcia Post Number: 79 Registered: 3-2005 |
Just to say that finally i have fitted the original plastic rad cowling that was missing in SRH3430. When fitting it i found that it could be disambled by a previous owner or mechanical because some after mounted tubes in the right lower side of the motor bay, in the bottom right side of the rad were disturbing its fitting. In fact, for fitting it, i had to practice an small hole for letting them to go through the cowling. Anyway, and about the high heating of the motor, i have to say, that i have no notice a real improve of the cooling. temp go as the same level that before fitting it. :-( Regards, Miguel | ||
| David Gore Moderator Username: david_gore Post Number: 487 Registered: 4-2003 |
This topic is now closed. |
