Author |
Message |
KC
Unregistered guest Posted From: 168.209.98.66
| Posted on Friday, 30 July, 2004 - 03:49: | |
What would be the recommended oil for a 4.25L Mk VI engine? Is Castrol GTX2 20/W50 suitable? What is the difference between GTX and GTX 2? They are both 20W50. Also, is Castrol EP90 (80W90) GL4 OK for the gearbox and diff? Kind regards KC
|
Bill Vatter Unregistered guest Posted From: 67.33.175.138
| Posted on Saturday, 31 July, 2004 - 00:29: | |
KC: Where are you? Different brands are available in different countries. Some points about oil: 1. Do not be concerned about using detergent oil in a sludgy engine. Long experience has shown detergent additives do not break up existing sludge deposits. 2. Early postwar engines put a lot of carbon particulate (soot) into the oil, and soot control is probably the biggest challange for the oil in your car. Soot is what turns the oil black. Soot that has precipitated out of the oil is also the main ingredient of sludge. Modern engines have very little soot problem, at least not until they are nearly worn out. Note that the oil in a modern engine turns amber, not black, as the oil accumulates use. Conversely, old RR engines turn the oil black. 3. One additive present in all modern engine oil is zinc dialkyldithiophosphate (ZDDP). This additive is usually referred to as an anti-wear additive, but is also very beneficial in controlling soot. Most recent spark-ignition-engine oil specifications call for less ZDDP than previously because ZDDP has been found to be adverse to catalytic converter life, and as stated above is not greatly needed for soot control. 4. Soot is controlled by keeping it in suspension. The oil filter will not take it out because in suspension it is a smaller particle than the pores in your filter. It also will not harm the engine because it is a much smaller particle than the clearance in the bearings. The oil filter is designed to remove particulate large enough to be harmful to engine bearings. If/when the soot particulate begins to clump up (soot control additive expended) it will begin to precipitate. That will be a problem for your engine. 5. Oil specified for diesel engines, American Petrolium Institute (API) specification CH-4, has more of the ZDDP additive than specified for API SL oil for spark-ignition engines, which is what you are currently using. (Note that diesel engines do not use a catalytic converter.) Bottom Line: Get oil for a diesel truck, for example Shell Rotella. Currently available in SAE 15W-40. That is what I use, and also many other knowledgable enthusiasts with cars like yours. |
Bill Vatter Unregistered guest Posted From: 67.33.175.138
| Posted on Saturday, 31 July, 2004 - 00:34: | |
For gearbox, use 20W-50 engine oil. For rear axle, use 85W-140 gear oil. DO NOT PUT GEAR OIL IN THE GEARBOX. Gear oil has extreme pressure (EP) additive, which is a sulphur-based compound, which has been found to be detrimental to brass, which is the material of some components in your gearbox. |
Richard Treacy Grand Master Username: richard_treacy
Post Number: 258 Registered: 4-2003
| Posted on Saturday, 31 July, 2004 - 02:11: | |
Hi there in South Africa (I seem to remember). To answer your question, GTX I, II and III are virtually the same but with increasing qualities reflected by their API indices, and come in various viscosity grades eg 15W40 or 20W50. Castrol recommends GTX (1) "for older engines" but I don't like its poor SH rating by the API. GTXIII is API rated at SL/CF, the highest performance ratings for petrol (SL) and diesel (CF) oils. Higher numbers of GTX than 3 (I have seen GTX 7 in Europe) start down the semi-synthetic path, but I don't see the point of semis. Personally, I use full synthetic 5W50, and in future 0W40, engine oil. A low viscosity when cold is a godsend to engine life, let alone the other benefits. Gearbox: do not exceed 40 grade: use 15W40 engine oil. Back axle: EP90 is fine, as are most universal extreme pressure hypoid multigrades. So, there's not much to the fluids in these cars, just whether to use mineral or synthetic engine oil. In any case, it's all sold in the supermarkets. |
KC
Unregistered guest Posted From: 168.209.98.66
| Posted on Saturday, 31 July, 2004 - 08:02: | |
Thank you very much Bill and Richard. Yes, I’m in South Africa. As far as I know we don’t get GTX 3 here. I use Castrol GTD in our diesel Land Rover. I think its 15W40, so perhaps I should give that a try. Many thanks! KC
|
Richard Treacy Grand Master Username: richard_treacy
Post Number: 259 Registered: 4-2003
| Posted on Saturday, 31 July, 2004 - 08:49: | |
Here is a site to compare Castrol oils. http://www.castrol.com.au/index_flash.html Use the vertical scroll bar near the right hand side. I don't really agree that high-soot tolerance would be of any benefit, even if the motor is burning excessive oil: in that case the problems will not be solved by putting diesel lubricating oil in your low-compression petrol motor. As always, look at the cost-performance benefits, but I would not pay a premium for GTD over GTX 2/3. I do for synthetic oils though. |
Ashley James
Unregistered guest Posted From: 62.255.0.5
| Posted on Sunday, 01 August, 2004 - 19:42: | |
R-R recommend gear oil for gearboxes in an attempt to protect first and reverse from chipping. I do not believe that there has been an additive in extreme presure oils that damages brass/bronze since the forties! I use 5-50 fully synthetic oil in both my MKVIs. |
Richard Treacy Grand Master Username: richard_treacy
Post Number: 263 Registered: 4-2003
| Posted on Sunday, 01 August, 2004 - 21:00: | |
Ashley, You have much more experience with gear oil than the rest of us put together, so you are surely correct. I thought that the only reason not to use heavy oil in the Mk VI transmission is that it makes the synchromesh stiff. That must be a red herring. |
Martin Cutler Unregistered guest Posted From: 211.30.116.216
| Posted on Sunday, 01 August, 2004 - 21:34: | |
Hi guys, I have had 90 weight gear oil in my gearbox for 15,000 miles, have had to rebuild the gearbox when the first gear retainer ring broke, allowing the gearbox the shift into reverse when it should have been in first. Not sure this was because of heavy oil or because of age. Car has only 100,000 miles on the clock. I was told that a later modification was made to the shaft to make the ring stronger through a larger ring. True?? The synchro's don't seem to be stiff, shifts very nicely hot or cold. In the engine I run Penrite HPR50, which is a quite thick oil, 40W70 viscosity. It was recommended to me by John Vawser, I run 30 - 35 pounds while driving, and hold 20 pounds pressure when idling, (engine hot). Should I be using a thinner oil? My overheating issues seem to have been sorted, although it is the middle of winter :-))) Chassis B256MD |
Richard Treacy Grand Master Username: richard_treacy
Post Number: 264 Registered: 4-2003
| Posted on Sunday, 01 August, 2004 - 21:54: | |
For Ashley's benefit, John Vawser started with York Motors in Alexandria, Sydney, then founded Campbell and Vawser, later John Vawser Motors, in Ultimo, Sydney, 1968, with support from Malcolm Johns. Malcolm, a well-known lawyer, has been a senior RROC (A) and BDC official for years, and has owned or still owns a Silver Ghost Barker Tourer, WOs, new Silver Shadows I and II, a new Turbo R and more. John Vawser has moved premises a few times, and was once in Crown St, Redfern (1976) and later William St, Alexandria (1981). He has seen my R-Type on quite a few occasions. I have a number of receipts for work done before my father let me loose on his then car, which has been mine since 1976. Martin, I am not a fan of thick engine oils, especially for cold running and short drives. It is definitely dangerous with a rebuilt motor. My R-Type runs 28psi hot or cold, and dips to 15 on idle when very hot with 5W50 Mobil 1 synthetic. It uses and leaks no oil at all (modern valve stem seals and piston rings). However, if a heavy oil cures oil pressure problems on a higher-mileage motor it is probably a valid option. Otherwise I would use 20W50, or preferably a good 5W50 synthetic. The 50 rating provides excellent oil pressure behaviour for any new motor and most high-mileage motors. |
Ashley James
Unregistered guest Posted From: 62.252.44.80
| Posted on Sunday, 01 August, 2004 - 23:54: | |
All I do is use what is recommended by Rolls Royce, I do not consider myself an expert on oils at all. The information came form the Service update bulletins I think. |
Bill Vatter Unregistered guest Posted From: 68.215.166.134
| Posted on Monday, 02 August, 2004 - 13:19: | |
Ashley, EP additive in gear oil is relatively new I think. Not there is the 1950s. Look on the bottle. If it says "EP" I would not use it. Of course the EP thing could just be an old wives tale. However, RR recommended SAE 30 engine oil not gear oil. If you want heavier oil, you could get some SAE 40 or SAE 50 ND oil. If it is not available locally, a small airport maintenance hanger can sell you aircraft engine oil in weights up to SAE 70. That will be detergent oil, but that will not really make any difference. When I was young and travelled cross country,on my Harley Davidson, I got oil at little airports. My gearbox is fine with 20W-50, 140K miles on the car. First gear is quiet, somewhat unusual. I think if I had a noisy gearbox, I would be looking for some heavier oil, but not the EP stuff. They say a noisy first gear is not a death noise.
|
Martin Cutler Unregistered guest Posted From: 211.30.116.216
| Posted on Monday, 02 August, 2004 - 22:30: | |
Thanks Richard. I might try a lighter oil at the next oil change. Bill, I have taken the side cover off my friends R type to look at what remains of first gear, after looking at it, my advice to him was to take off in second gear! The car is very noisy in first, but refuses to die, still going strong! Marty |
John Dare Unregistered guest Posted From: 144.138.194.57
| Posted on Thursday, 12 August, 2004 - 06:54: | |
Engine oil/s; John Vawser, who has probably performed more work on R-R/B cars than anyone, rebuilt the engine on my "R" Type (B10TN) and rebuilt it PROPERLY, following a "world expert" $20K re-build (so called) where the new pistons had begun to scuff after only 1500 (one thousand five hundred!) kms., not to mention virtually no oil feed to the crank/cam timing gearset!. John personally ran the engine "in" (driving it for about 2 weeks)using lighweight "running in" oil, after which I flew up to Sydney to enjoy a most memorable drive back to Melbourne via the Blue Mountains.During that time, engine temp. and oil pressure (since tested with independent gauges!)were excellent, using HPR30, this being confidently suggested by John as the best oil to use here in Australia. I am also a somewhat permanent "custodian" of a friends "R"Type (the FIRST standard steel saloon built;B20RT, delivered by Franco Brittanic to Brussels) and use it as often as I can whilst he holidays around the world (Geneva,Berlin and all that) That car has been to the moon and back and I get moist eyes when it charges up long hills in absolute defiance of its years and mileage. Oil is HPR70, which I change regularly, along of course, with Bill Vatters excellent "spin on" oil filter adaptor, just like on my 1970 Shadow. Again, good oil pressure and eng.temperature in this "R" Type too, even with the air cond.(as fitted by him) operating on 30C days. More facts, as trialled and proven in the real world! |
Ashley James
Unregistered guest Posted From: 62.252.44.10
| Posted on Thursday, 12 August, 2004 - 18:56: | |
R-R recommend fully synthetic oil in all their engines since day one, but after an engine rebuild. Ken Lea was more comfortable with semi synthetic oil if engines have not been rebuilt. The message is simple: Old oil used to be major cause of engine wear but, as R-R say "if you use fully synthetic oil you may never have to rebuild again" EP80/90 gear oil is roughly the same visocosity as 30 grade engine oil - visocosity varies with operating temperature and gearboxes run cooler. Either in the Service Update Bulletins or the MKVI handbook R-R recommend a change from engine to gearbox oil. They did this to try and reduce damage that was occurring to first and reverse gears Anyone interested in oil arguments ought to obtain Club Technical manual number 5 from the RREC shop. In it they will find everything they need to make a decision they are comfortable with. I lay the blame for these endless oil discussions on totally incompetant Ad agencies, they have singularly failed to communicate the benefits of synthetic oil in particular, to end users. Old wives tales predominate! |
Bill Vatter Unregistered guest Posted From: 68.158.17.89
| Posted on Friday, 27 August, 2004 - 01:38: | |
I have just returned from the US RROC annual meet in Monterey, California, a round-trip for me of about 6000 miles in my Silver Wraith. At the meet, I attended a lubrication seminar led by Will Fiennes, who is a Tribology PHD. Will explained two important points about the "EP" additive in gear oil: 1. It only works in a boundary lubrication environment and where the local temperature (at point of contact) reaches very high values, which conditions are only present in HYPOID gears which are only used in the crown/pinion of the rear axle, and only from about 1936 onwards with the P-III and Wraith. Everywhere else, "EP" additive does nothing. 2. Early "EP" formulations used sulphur and phosphorous compounds, which were harmful to copper-based alloys (brass & bronze). Current "EP" additives are much more copper-friendly, and concerns over their use in gearboxes are no longer valid. Note however, that the "EP" isn't doing you anything in a gearbox. The principle advantage of synthetic oil is a very high natural viscosity index, meaning it does not thin out as much as mineral oil when hot, and less or no VI improver additive is needed to maintain viscosity when hot. |
John Dare Unregistered guest Posted From: 144.138.194.24
| Posted on Friday, 27 August, 2004 - 08:12: | |
Thank you Bill; Point 2 of your post bought back old memories about the "special" oil/s specified for "Peugeot" 403s etc., with their worm/wheel final drive arrangement, the "worm" drive, I recall (from memory) being of bronze etc. Technological progress is a marvellous thing which allows us all to move forward. Having said that,I spend more time thinking (and worrying!) about the "best/correct" oil than anything. Well.. almost anything. Wish you hadnt raised the subject.(joke) |
Ashley James
Unregistered guest Posted From: 62.252.40.29
| Posted on Saturday, 28 August, 2004 - 18:33: | |
The stated advantages of synthetic oil are as follows: 1. That is thinner when cold and more quickly reaches important places on start up. 2. That it clings to surfaces for longer during periods of inactivity and thus offers more protection on start up. 3. That it withstands higher temperatures and pressures than conventional oil without film breakdown. Our engines have more of these than modern engines. 4. It maintains its viscosity to higher temperature (not quite the same as number 3) 5. That is does not dissolve so easily in petrol and so protects against washing petrol off top rings when the choke is out. These claims are made by the oil companies and verified by a number of motor manufacturers including BMW and R-R who now recommend it for all models as I previously explained. These are substantial advantages by any standards. |
Jeff Martin
Experienced User Username: jeff_r_1
Post Number: 65 Registered: 07-2018
| Posted on Wednesday, 17 June, 2020 - 03:17: | |
Rather then start a new thread, it made more sense to post here. Interesting reading, my only complaint about my transmission (4 speed manual 1951 MK VI Bentley), is when shifting into 4th gear, it has to be done carefully, pausing for a few seconds in neutral and gently putting it into 4th. If one does it too quickly, it will go in with a bit of a grind. Double clutching will also keep the slight grind from happening. I'm running Pennzoil 80/90 weight gear oil, it's very thick and sticky, will a lighter oil help with the synchro from 3rd to 4th ? I'm not worried about sulfur in the what I use now, I wanted to know if I use 20w-50 weight motor oil, if that will help with my grinding problem ? Maybe the synchro is worn and putting a lighter weight oil in there will make it worse ??? All other gears shift really well _ reverse too. |
Jim Walters
Frequent User Username: jim_walters
Post Number: 315 Registered: 01-2014
| Posted on Wednesday, 17 June, 2020 - 04:35: | |
Jeff, the best product you can use to improve the synchro operation in your gearbox is Redline MTL 75/80 (Manual Transmission Lubricant). I have used it extensively in British gearboxes for many years and if there is any improvement to be had, it will do it. The results have been amazing at times especially when used in Morgan and Jag Moss boxes which have traditionally weak synchros. SRH8505 SRC18015 SRE22493 NAC-05370 www.bristolmotors.com |
Christopher Carnley
Unregistered guest Posted From: 109.159.182.244
| Posted on Wednesday, 17 June, 2020 - 04:52: | |
Jeff, You have a problem with the gearbox, maybe the 3rd speed thrust washer has broken, jamming the synchronisation.
(Message approved by david_gore) |
Jeff Martin
Experienced User Username: jeff_r_1
Post Number: 66 Registered: 07-2018
| Posted on Wednesday, 17 June, 2020 - 09:32: | |
Thanks, I will try that Jim. I suspected as much Chris, it's been like that since I have had it, more then 20 years, and it's never gotten any worse. I was cleaning up the servo and dealing with some oil leaks and pondering how to get the trans out. It doesn't look like there is enough room to withdraw it from the bell housing. The input shaft will never clear because the back end of the transmission will come in contact with the "X" in the middle of the frame. It's a winters project, so I'm not going to worry about for now, it's just the beginning of our summer. |
David Gore
Moderator Username: david_gore
Post Number: 3717 Registered: 04-2003
| Posted on Wednesday, 17 June, 2020 - 15:49: | |
Jeff, Corniche DRH14434 had a similar "cruciform" brace under the passenger compartment floor to stiffen the convertible body structure. This had to be removed to allow removal of the automatic transmission for overhaul. I did this at the time and removed the transmission without any problems. After the transmission overhaul was completed, the transmission reinstalled and general tidying up of the underneath of the vehicle, it was time to reinstall the cruciform brace. You can guess what I found - the body structure supported on front and rear heavy duty floor stands had sagged slightly and the mounting points for both the brace and the body were no longer aligned for easy reinstallation of the bolts. The solution was both simple and complex, I mounted the brace on the body mounts closest to the engine and then assessed what to do next. A simple solution suggested itself - put a timber cross-piece and appropriate supporting blocks for the body under the centre of the cruciform brace and use a hydraulic floor jack to lift the body and see if the rear brace and rear body mounts would realign. Against my expectations, this worked first time with the bolts sliding smoothly into place and being tightened to specification. The cross-piece and blocks were removed and the car lifted from each end to remove the floor stands. The mounting bolts were rechecked and found to be still compliant with the torque specification - they were checked again a month later after the car had been driven on a daily basis and found to be still compliant. One very relieved DIY custodian after solving a problem with possible major rectification difficulties. |
Jeff Martin
Experienced User Username: jeff_r_1
Post Number: 67 Registered: 07-2018
| Posted on Wednesday, 17 June, 2020 - 19:02: | |
David, Well this is bit embarrassing, I had another look under there and all that needs doing is to remove the rear transmission support bracket (for bolts). This will allow the trans to slide back to clear the rear of the bell housing with out coming in contact with the "cruciform". It's actually a nice arrangement being able to remove the trans with out having to deal with the bulky bell housing. The car doesn't have to be lifted so high to make room, although the car only has about another foot until it's touching the ceiling of my garage. |
Christopher Carnley
Unregistered guest Posted From: 109.159.182.190
| Posted on Wednesday, 17 June, 2020 - 18:40: | |
Jeff, It does, but you have to remove the prop shaft. All is elucidated in Section F of the Workshop Manual, the Clutch Section.The servo has to come off as well as the selector shaft. You can,t remove the bell housing due to its proximity to the bulkhead, and the clutch plate has a special central boss to allow it to drop out of the bottom when the steel sheet cover is removed. C.
(Message approved by david_gore) |
Bill Vatter
Experienced User Username: bill_vatter
Post Number: 109 Registered: 09-2004
| Posted on Wednesday, 17 June, 2020 - 23:25: | |
The difficult part is accessing the upper nuts that hold the gearbox on the clutch cover (bell housing). I recall the top right one is the worst. The Service Instructions tell you to remove the floor, not always easy due to rusty fasteners. It is possible to lower the back of the gearbox-engine assembled unit to open up the space enough to get a spanner in there. Even then, you can't see it.... need to work by feel not sight. You will need to disconnect several things to achieve sufficient motion. I remember exhaust pipe(s). May be other items. Then your spanner probably still difficult to get sufficient motion. I cut a combination spanner in half and maybe also ground on the ring end to get it to slip on. That now special tool is ground thin, maybe done for that; maybe something else. If you had full access you would be using a socket. |
Jeff Martin
Experienced User Username: jeff_r_1
Post Number: 68 Registered: 07-2018
| Posted on Thursday, 18 June, 2020 - 14:30: | |
Bill Had a look at those two inaccessible nuts, the only thing that will work (on mine) is an open end wrench (right now). The aluminum casting is so tight up against the nuts, that no box wrench would go on. However, I did get the one on the starter side to move, so I could have gotten that one off. The one where all the brake and clutch linkage is gets in the way, so that would all have to be removed, but still better then removing the floor. Once the trans is removed, it wouldn't take much to create enough space to get a box end wrench on it, I would say about 1/8 of material would have to be removed. Once a box end wrench would be made to fit, it would be easy, I have long arms and skinny long fingers. Getting a socket on would be impossible no matter what, it's designed in such a way that a socket could not be used. The trans casting takes a sharp curve, so there is no clearance for a socket. I don't know what it is with RR, why do they design things in this manner where only an open end wrench will go on. The nuts on the exhaust are like this, both where it bolts onto the block and the downpipe. The nuts that hold the lower distributor housing where it meets the block are the same, in fact they are so close, the points on the nuts are rubbing against the aluminum. Looks like the nuts on the rear end are the same. I've ground off some of the casting on the manifold so I could get a box wrench on. I'll post again once a have put the new oil in. |
Bill Vatter
Experienced User Username: bill_vatter
Post Number: 111 Registered: 09-2004
| Posted on Friday, 26 June, 2020 - 08:00: | |
Try grinding a ring spanner on the outside to make the ring thinner. The worst that can happen is that you destroy the spanner. The gearbox case is a casting, so there will be small variations of dimensions and clearance between the nut and the case. All I can say about it is that a ground ring spanner worked for me on 5 gearboxes and failed on none. 12 points on the spanner will double the variations in ways you can put it on compared to an open-jaw spanner and you need that to turn the nut. The nut cannot be turned 30 degrees in one motion without bumping into something, and 30 degrees per swing is the minimum you can get using an open jaw spanner with a 15 degree offset end, flipping it over between swings. A 12 point ring spanner will reposition 15 degrees when you turn it over between swings (360 / 12 / 2), and with that, you can get the nut off. You will also need a short handle, which you get by cutting the spanner in half. The nut will probably be too tight to get it moving with the short handle and the awkward way you have to hold it so you will need something to lever on the end if it. Count the times you drop the spanner. My record is over a hundred on that upper-right nut. Hopefully you have a lift so the spanner hits the floor and not your face. No one said it would be easy. Success at a challenging task is satisfying. |
Jeff Martin
Experienced User Username: jeff_r_1
Post Number: 148 Registered: 07-2018
| Posted on Saturday, 10 October, 2020 - 05:53: | |
This is an update about the trans oil (Redline MTL 75/80) from Jim's recommendation. It has made an improvement, while it has not cured the slight grind into 4rth gear, it has reduced the tendency to "grind". At any rate, I have to drop the trans anyway to repair a leaky cam-shaft cover at the back of the engine, I will have Jim dismantle the transmision and inspect the suspected thrust washer. About the synthetic 10w/30 oil that I have been running. The oil is very noticeably cleaner on the dip stick after a number of weeks of driving and many miles. Where it would be getting dark already, it is still very clean and transparent. This may be due to the synthetic WIX spin on filter that I have fitted as well. The other thing said about synthetic oil is that all the molecules of oil are the same. This allows the rings to seal better and this in turn prevents compression gasses entering the sump. This is turn keeps combustion soot out of the sump. The clean oil on the dip stick would indicate that there is some truth to this. As mentioned before in other threads, I am running the hotter thermostat of 88 degrees and the mixture is set for best performance and good spark plug colour. This also is responsible for the clean oil on the dip stick. |
Norman Geeson
Unregistered guest Posted From: 81.99.138.38
| Posted on Sunday, 11 October, 2020 - 19:06: | |
Worth noting here is that in engine tests by R-R they found a 13C differential between coolant at the rear of the engine and that at the thermostat point. This was one reason they fitted a 73C/75C to keep rear end temperatures down, except for Canadian deliveries when 78C (?) stats were fitted. In short, if you can crack a 88C thermostat open you risk boiling at the rear.
(Message approved by david_gore) |
Jeff Martin
Experienced User Username: jeff_r_1
Post Number: 155 Registered: 07-2018
| Posted on Monday, 19 October, 2020 - 11:48: | |
When I did my engine I found a square rectangle tube full of holes that ran the length of the block, I'm going to assume that this was put there to help with that problem. I also removed the restrictor in the heater tube that goes from the back of the head, this should also help with that problem even if the heater fan isn't running. Where would one find a new 73/75C degree thermostat, the only ones listed are 78 and 88 degrees ? At any rate I'm not going to worry about it, the 88 degree one has been in there for many years, and nothing bad has happened. Maybe if I had the original deep split skirt pistons maybe there would have been a problem. If I'm curious enough, I may install another bourbon tube temperature gauge at the back of the head where it feeds the heater matrix. |
Bill Vatter
Experienced User Username: bill_vatter
Post Number: 129 Registered: 09-2004
| Posted on Wednesday, 21 October, 2020 - 10:28: | |
Wow !!! So many things being discussed in a topic Titled "Mk VI Engine Oil." Recent posts include: 1. How to remove the gear box 2. Elevated coolant temperature at the back of the engine 3. Water pipes and tubing connecting the heater. 4. The water distribution gallery (I think that is what was meant by "Square rectangle tube full of holes.") 5. Leaking rear camshaft cover 6. Using synthetic oil to help seat new piston rings. At least that last one is about engine oil. There may be other topics I did not see. Perhaps David Gore will disassemble this thread and separate the discussion so that it can be referenced by those seeking info on the various subjects addressed. David, How do you like that challenge? Maybe just the title can be changed "All about the EPW engine and gearbox" Expecting David will not take the bait, I have a couple of comments on the recent posts. I believe the flow restrictor in the heater supply pipe is there to protect the heater matrix from overpressure. I don't think the heater matrix can take the full differential pressure of the water pump and survive with reliability, so a flow restrictor, which also provides pressure drop upstream of the heater was fit in the supply pipe. I also believe this flow restrictor was not there on the first cars, but added afterwards. Further, I think I read somewhere it was to protect the heater. Perhaps Norman knows the details of that. Anyway, for cars with heater taps near the back, more flow to the heater would probably increase flow at the rear of the engine and help cool that part a little more. Removing the gearbox to access the camshaft rear cover is very interesting. I do not believe it is possible to get that cover off without removing the engine from the car. Certainly the gearbox won't improve access, but if it can be done, it would be worth knowing how. The camshaft part number is stamped on the back end of the camshaft, and if you want to verify camshaft timing or reset it with the engine in the car, that is information one should know first, and taking off that cover is how you can take a look at it. It could be a toss-up. Take out the engine or take out the camshaft, which is more work? The water gallery was modified several times by the factory, which I think was for the purpose of maximizing cooling of the cylinder deck bridge, the surface between the cylinder bore and the exhaust valve. That is the hottest part of the block, and inadequate cooling there has caused some blocks to crack. Usually the crack begins at the exhaust valve seat, and it is a good reason to fit a hard steel exhaust valve seats when you overhaul an engine. Cheap protection against expensive problems (cracked block). Maybe not complete protection, but every little bit helps. Back to the gallery. Norman wrote a VERY comprehensive article, which I think was titled "Cylinder Blocks and a Few Deviations," or something like that. You can see it on KDA132.com. If you want to know about water galleries, that's where to look. Different pistons make the car more or less sensitive to overheating conditions. Hmmm. An interesting idea. And there’s probably something to it, but how would you know which pistons are best from that perspective? My opinion, the best EPW pistons are from JP Engineering, an Australian company, maybe carrying a different brand name now. I have used a few sets of those, and have had no problems. Same stories from others, and I haven't heard different. They did have problems shipping, arrived with dents in the skirts, but that is not the piston's fault. Uniform molecules to aid seating piston rings is amazing. That sounds like a marketing pitch. There is always uncertain truth coming from the marketing people. I don't believe it at all. Lastly, and I know you didn't mean it, but I cannot resist. A "Bourbon tube" at the back of the engine. ???? "Bourbon tube" sounds like a straw for discretely sipping whiskey. Maybe you tried to write Bourdon tube, and it is a typo. OK, I have had my fun and I'm done. Shields up, let me have it. |
Jeff Martin
Experienced User Username: jeff_r_1
Post Number: 156 Registered: 07-2018
| Posted on Wednesday, 21 October, 2020 - 11:23: | |
I have a new heater matrix, not the "pie plate" type, so I don't think it would make any difference. The system isn't pressurized anyway, at least mine isn't, would it even make a difference ? I can't see that somewhat feeble water pump putting that much pressure on any matrix to do it any harm. Once the gear box is removed, the bottom bell housing cover is removed. This allows access to the clutch and flywheel. Once those has been removed, there is plenty of room to get at the cam shaft cover. I can see there will be lots of room, shinning a pen light up there. My new pistons have very short skirts as apposed to the RR deep skirt piston's Less metal contact on the bores _ less friction _ less heat _ that's my thinking anyway. And so far it has never over heated, that's in 34 degree C _ stuck in traffic, piddling along at 30km and hour _ weather. My engine has had hardened exhaust seats installed, there was nothing left of the block to machine in that respect. About the oil, that is what I've read, it would seem at this point to be true, or it could be the fancy WIX synthetic filter. Yes. Bourdon tube. I checked. I'll blame that one on my Dad, that what he told me, and I've always written it that way all these years, you are the first one to correct me. Like "pinking" or "pinging" I can see an engine pinging, but pinking, "yes, your engine sounds like Pepto-Bismol today" ? And now that I think about it, every RR and Bentley should have a Bourbon tube for sipping ! Or in my case, chocolate milk. |
David Gore
Moderator Username: david_gore
Post Number: 3818 Registered: 04-2003
| Posted on Wednesday, 21 October, 2020 - 13:32: | |
Bill, I have been preoccupied with family matters today and will sit down tonight and split the topic into individual sections plus add the relevant responses to each item. |
Bill Vatter
Experienced User Username: bill_vatter
Post Number: 130 Registered: 09-2004
| Posted on Wednesday, 21 October, 2020 - 22:29: | |
David, Wow! You reaally are dedicated to having an excellent resource for RR technical experience data. Hat's off. Does not seem like a small job. I have heard about alternate heater matricies to get more cabin heat. Interested to discuss it further. I have changed fan impellers (blower wheel), which improves air flow significantly. It's from a bathroom exhaust fan. Not ideal size or shape, but moves a lot more air than the original. Any heater will be limited in its capacity by one of several different parameters. I see heat transfer area, air flow, and water flow as the major possibilities. I think air flow is the limiting factor for the RR heater, simply because when I stick my hand down there, I feel there's not much air moving. Pretty crude analysis method. Introcar is selling a similar-looking heater core with a fundamentally different internal design, so maybe there is something to the matrix being the problem. Could also be the original design very expensive to manufacture, which I'm sure is true. It's complex with lots of soldering; must be labor-intensive to assemble.. Would also like to discuss other things further, but I'll wait. |
David Gore
Moderator Username: david_gore
Post Number: 3819 Registered: 04-2003
| Posted on Thursday, 22 October, 2020 - 06:46: | |
Sorry chaps, I forgot I had to log in on-line to last night's RROCA NSW Branch October Meeting as there was a guest speaker participating who I wanted to hear. Raining this morning so should find time to complete this task today. |
Trevor Pickering
Experienced User Username: commander1
Post Number: 162 Registered: 06-2012
| Posted on Thursday, 22 October, 2020 - 17:26: | |
I can confirm that it is very easy to access the rear camshaft cover once the gear box has been removed having recently done this. Just a lot of work!!!!!!!!!!!! |
Christopher Carnley
Unregistered guest Posted From: 77.234.43.174
| Posted on Thursday, 22 October, 2020 - 18:19: | |
Jeff, Why are you removing the circular rear camshaft cover?
(Message approved by david_gore) |
Jeff Martin
Experienced User Username: jeff_r_1
Post Number: 157 Registered: 07-2018
| Posted on Thursday, 22 October, 2020 - 23:41: | |
Because it's leaking like a sieve. |
David Gore
Moderator Username: david_gore
Post Number: 3826 Registered: 04-2003
| Posted on Saturday, 24 October, 2020 - 14:24: | |
Bill, I have not been able to find a way to split individual posts for reposting as as you suggest as I cannot post split posts using the name of the member who wrote the original post on the split posts. Best to "let sleeping dogs lie" and rely on the Google Search facility as our Administrator changed the access permissions some time ago to allow Google access to the forum archives. . |
Bill Vatter
Experienced User Username: bill_vatter
Post Number: 132 Registered: 09-2004
| Posted on Sunday, 25 October, 2020 - 00:03: | |
I figurex somethig like that. Why I said seemed like it would be a big job. |
David Gore
Moderator Username: david_gore
Post Number: 3829 Registered: 04-2003
| Posted on Sunday, 25 October, 2020 - 06:39: | |
Bill, I think it is a privacy issue to prevent posts not made by members other than edits or deletion by Moderators/Administrators being created. |
Jeff Martin
Experienced User Username: jeff_r_1
Post Number: 158 Registered: 07-2018
| Posted on Sunday, 25 October, 2020 - 11:13: | |
I need to amend one of my statements, I should have said, "synthetic oil helps to seal the rings on the bores, not, "seat" the rings". That comes from what I read about the molecules being all the same size. When the molecules of oil are all the same size, you get them packed more close together, this in turn also helps with cold start up on the bearings. The oil stays put better, you don't have the smaller molecules escaping between the larger ones like in conventional oil. And because they are all the same size and packed closer together, there is less blow-by by the rings. It makes sense, even if it does sound like a marketing ploy. Moderator comment - Now corrected. . |
Trevor Pickering
Experienced User Username: commander1
Post Number: 166 Registered: 06-2012
| Posted on Sunday, 25 October, 2020 - 18:29: | |
Jeff The rear cam shaft cover seems like an unusual place for an oil leak. |
Jeff Martin
Experienced User Username: jeff_r_1
Post Number: 159 Registered: 07-2018
| Posted on Monday, 26 October, 2020 - 04:53: | |
After dealing with the sump, I started the engine and watched the last place where it was leaking. I watched the oil seep out from under the cover while the engine was running. When I did the engine I used this crappy Permatex gasket sealer. It looks like thin black tar and one would think it would do a good job, but it gets rock hard after a number of years and does nothing to seal. I had put it on the sump gasket too, totally useless stuff. |
Trevor Pickering
Experienced User Username: commander1
Post Number: 167 Registered: 06-2012
| Posted on Monday, 26 October, 2020 - 16:58: | |
Can I recommend that you use Wellseal Jeff as this will solve your problem. Wellseal was developed by Rolls Royce and manufactured under licence and was used very successfuly to solve oil leaks on the Merlin engines. I have used this for years and it works. |
Christopher Carnley
Unregistered guest Posted From: 159.242.227.44
| Posted on Monday, 26 October, 2020 - 19:23: | |
Thin oil paper is best if the machined surfaces are undamaged, with Wellseal and you may never get it off. How are the fixing screws / bolts sealed on yours? It is also a big mistake not to use the soft pine dowel seals for No 7 main bearing seal.
(Message approved by david_gore) |
Jeff Martin
Experienced User Username: jeff_r_1
Post Number: 160 Registered: 07-2018
| Posted on Tuesday, 27 October, 2020 - 06:24: | |
Thanks, I've been using this, Loctite 515. It can be used with or with out a gasket. It works really well to hold the gasket in place in awkward areas _ doesn't cure until there is no oxygen present. Maybe Wellseal does the same thing. https://www.henkel-adhesives.com/ca/en/product/gasketing-sealants--flange-sealants/loctite_515.html |
Patrick Lockyer.
Grand Master Username: pat_lockyer
Post Number: 2392 Registered: 09-2004
| Posted on Tuesday, 27 October, 2020 - 07:46: | |
Nothing like the proper thing when all else fails! Been using the product for years. https://www.frost.co.uk/hylomar-universal-m-aerosol/ https://www.newmantools.com/chemicals/hylomar.htm |
|