| Author | Message | ||
     Jeffrey McCarthy Frequent User Username: jefmac2003 Post Number: 94 Registered: 5-2007 |
I've had my aircon system on SRH20280 tested by a local shop in Albury. The car hasn't had gas in it for a very, very long time - I think the old stuff was just removed and it was never filled with the new stuff. The compressor seems okay and I've read all the info here. It's the standard GM SS1 system. All the actuators and flaps are working. However when I suggested to the guy that the new charge should be weighed (just under a kilo) he corrected me and said that it was a specific QUANTITY of liquid that had to go in. Does anyone know if this is correct/ just another way of saying the same thing? Also if the suction throttling vavle is working is it worth removing it anyway or better to just wait till it goes bung. The cost with various bits (seals and new inlet valves included) is about AU$530 which is less than I was prepared to pay(I thought the compressor might be gone) However - with compressor - what is it that does breaks down in them and if/when they do can they be rebuilt or is it more cost effective to replace them? Any advice/horror stories would be appreciated. Cheers, Jeff | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 1581 Registered: 4-2003 |
This document should be enough for the R134a data conversion, http://rrtechnical.info/miscellaneous/r134.pdf However. Use it for your own reference and interest value only. Leave it all strictly to your aircon shop to determine the oil and charge requirements. They do it all the time. Any good shop will set the quantities with no fuss, evacuating the system with a vacuum pump, then using the correct compressor oil and quantity before charging the system. If they can't, find a shop that can. Suction throttling valve. Leave well alone unless it leaks or malfunctions. They are a good device, but the alternative works just as well on billions of cars and is equally effective by cycling the compressor. The shop may or may not understand a STV, but they will learn fast. Your GM compressor and clutch are designed to cycle, but Crewe simply didn't like the regular click although you can only hear it when stationary. STVs are replaceable, and you my buy a repair kit to repair yours. They are available from the likes of Introcar ex-stock. UK suppliers will also sell you a conversion kit devised for your car to delete the STV and to cycle the compressor instead, similar to the kit specified and offered by Crewe at a silly price. Important is that the refrigerant switch be fitted to cycle the compressor as in practically every other refrigeration system including the fridge in your kitchen. Any aircon shop will do the modification at a far lower price than buying a kit. They will use their own components at a negligible price rather than using a relatively expensive kit. It is no good simply blanking out the suction throttling valve as it can only cause problems and copmpressor failure or worse, so you need the refrigerant switch to trigger the cycles. Cars from SZ 20000 use the cycling system from new. Please, don't take on your shop's job. It is their responsibility to determine the charge. If you specify anything yourself, they will only blame you for any problems. Believe me, our aircon shops in Canberra (I have used two) can do all this standing on their heads. They have been recharging compressors for decades, and certainly don't need any of the information you mention from any customer.¨ RT. | ||
| Jeffrey McCarthy Frequent User Username: jefmac2003 Post Number: 95 Registered: 5-2007 |
Thanks Richard, I guess I was just being a bit paranoid about it all. Cheers, Jeff | ||
| Bill Coburn Moderator Username: bill_coburn Post Number: 1077 Registered: 4-2003 |
Can I add to Richard's advice. As I understand it the compressor alone is a fairly critical bit of equipment when operating. The refrigerant has to reach it as a gas and there has to be a fairly precise fog of oil in it. All of this is under pressure retained by seals at various points in the system. If the STV or the later replacement on the early Spirits lets liquid refrigerant through to the compressor, when those little pistons strike a block of solid liquid they tend to break.and if the oil in the system dries out or is lost the seals go hard and the gas escapes to the atmosphere and buggers the ozone layer. The hoses on older cars leak as do the evaporators and the back of the compressors. All this to iterate Richard's advice - leave it to the professional. There is also another reason to do this, only they are licensed to service the equipment, if you do it it is illegal! | ||
| Jeffrey McCarthy Frequent User Username: jefmac2003 Post Number: 96 Registered: 5-2007 |
Thanks also Bill. I wasn't intending to do it myself, I'd just read in the forums that there had been cases where aircon guys had put the wrong quantity of liquid in and caused damage. I've become a bit (over?) cautious about who gets to work on the car after a bad experience with a young auto-electrician who wasn't very familiar with fuse wire -- he wrapped 10amp fuse wire around the fuse in 5 layers. Also it never hurts to ask - it's good to at least understand what the professionals are talking about. The guy at the shop told me that he thought the compressor would be okay after the initial tests but with one that is this old you can't really tell what shape they're in until you use them. I'm assuming that all the seals should be replaced as a matter of course - I think it's probably about 10 years since the system has had anything in it so they should be fairly dried out by now! If however the compressor does break down, is it better to replace it with a newer one or can it be repaired? Cheers, Jeff | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 1582 Registered: 4-2003 |
Leave it to him. He will probably use an electronic leak detector wand immediately, then put in a dye, as checks before ripping it all apart. Any unlikely leaks at the compressor (not primarily age-dependent by the way), or mor commonly the hoses or STV, will show up straight away. Compressors are like sleeping dogs: best not kicked. | ||
| Jeffrey McCarthy Frequent User Username: jefmac2003 Post Number: 97 Registered: 5-2007 |
Not primarily age dependent is good news! Definitely won't be kicking any sleeping dogs then... :-) | ||
| Bill Coburn Moderator Username: bill_coburn Post Number: 1078 Registered: 4-2003 |
Jeff please don't let me discourage you from knowing about our cars - that is the very thing I try to encourage the tea and scones mob to do. I try to explain that they don't have to get their hands dirty just try and have some empathy with the functioning of the car. As to compressors I have used both reconditioned and new ones and now I always use new. You would not be likely to repair yours simply exchange it for a reconditioned one. For the extra couple of hundred to me a new one seems worth it considering the amount of work to fit them and recharge the system. Incidentally I did not mention that it is good practice to use the airconditioning at least once a week to keep the seals etc moist. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 1584 Registered: 4-2003 |
Agreed, Bill. Yours repaired is probably OK if the defect is minor and easily repaired, like the rear seal. If any other problem arises, a repair may just be throwing good money after bad. Exchanges are buying someone else's problem, probably a compressor more stuffed than yours to start with. Why else would a compressor be exchanged on the never never ? Repair yours if minor, new (only brand spanking new I mean) if medium. | ||
| Jeffrey McCarthy Frequent User Username: jefmac2003 Post Number: 98 Registered: 5-2007 |
Yep - if it's anything but the seals I'll tell him to go for a new (brand spanking !)one - at least that would come with some peace of mind (and presumably a warranty!) Thanks again for the advice. | ||
| John Kilkenny Frequent User Username: john_kilkenny Post Number: 72 Registered: 6-2005 |
Jeffrey, Car air conditioning is not rocket science and local shops are quite capable of working on them. My system was the same as yours and has been upgraded as follows... Initially (in 2002) it was losing refrigerant the cause of which turned out to be a leaking Suction Throttling Valve. The cost of a new one (or even a repair kit) was excessive and the aircon technician (Denmor Auto Electrical in Sydney) recommended getting rid of it, which we did. I see that Introcar currently sell a similar kit for 129 pounds which replaces the STV with a temperature sensing device that cycles the compressor clutch. At that time it was still possible to get reclaimed R12 so this was used for my system. Also at that time a low refrigerant pressure detection switch was added to the clutch circuit as a safety device, as required by law. Five years later the aircon failed again due to low refrigerant pressure. At Robert Chapman's recommendation I took the car to Bold Auto Electrics in Box Hill Melbourne, who checked for leaks then replaced the refrigerant with HR12, a hydrocarbon based refrigerant which enabled the retention of the original receiver/drier. Since then the aircon has worked well with plenty of cold air. I suggest that before you spend any money, charge the system with HR12, check that the STV actuator is operating properly and if there are any leaks in the system. Regards, John | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 801 Registered: 9-2004 |
Jeffrey, with regard to your first posting: "I think the old stuff was just removed and it was never filled with the new stuff. The compressor seems okay and I've read all the info here. It's the standard GM SS1 system. All the actuators and flaps are working. However when I suggested to the guy that the new charge should be weighed (just under a kilo) he corrected me and said that it was a specific QUANTITY of liquid that had to go in. Does anyone know if this is correct/ just another way of saying the same thing?" The weight of the refrigerant charge is 38oz, the oil is 190cc. If the system is not flushed then 3 to 6 ozs of oil should be added. IMO I would pressure test, still replace all the flexable hoses and o-rings fit a new receiver drier,STV, and then retrofit to R134a. Checking with the compressor maker if it will run on R134a first. As for useing HR12[hydrocarbon-based] you had just as well use [LPG] propane! if a leak accours through an accident or a flexi hose failure etc, you will have a fire ball. All refrigerants are violently flammable when the refrigerant rushes out, creating an aerosol mist of oil but the R134a will not engulf the car ETC in a fire ball. | ||
| Gus Brogden Experienced User Username: gus Post Number: 22 Registered: 2-2008 |
If you are retrofitting from R12 to R134a, you need to change the compressor oil to a PAG oil. 134a will have a reaction to the residual mineral oil and cause coagulation, disallowing proper oil return, with the results a seized compressor. I believe Copeland and Tecumseh recommend a residual mineral oil content of <5%. Changing the compressor oil and receiver dryer should remove enough mineral oil, but I would let it run for about 15 min and then take an oil sample to check its refractive index to make sure. I have seen many seized compressors after R12 to R134a retros, and have seen crankcase oil like "silly string" in piping, with no oil in the crankcase. If you cant use a refractometer to check refractive index, I would at least give it an extra oil change after running for a half hour. You can use the same R12 compressor for R134a, the two refrigerants have similar pressure/temperature characteristics. The oils ARE NOT compatable. Pressurize your system with dry nitrogen 1st to leak test (100psi max!), because unless your car was imported and disallowed entry with R12, I dont see why it would be purged. There is only one other place for it to go. A small leak on R12 will be a big leak with 134a, as 134 is a much smaller molecule than 12. Pay attention to the compressor crankcase seal (behind the pulley) and o rings. Oil stains are tell tale signs. 50/50 dish suds and H2O will show leaks. DO NOT run the AC with nitrogen in the system!! PAG oil is very hygroscopic, worse than RR363. Buy it in small containers and keep closed. After retrofit with 134, you will experience a few bubbles in the sight glass on the reciever. Charging to a clear sight glass will be overcharged. You will experience about 10% less cooling on 134 compared to 12. | ||
| John Kilkenny Frequent User Username: john_kilkenny Post Number: 73 Registered: 6-2005 |
Patrick, While it is very dramatic to talk about fireballs due to hydrocarbon refrigerants, the fact is that any release of vapour from a car air conditioner is flammable due to its oil content. The fracture of fuel lines in a car running on petrol or lpg is just as likely to result in a fire, probably more so as there are only a few hundred grams of refrigerant in a system. HR12 is a mixture of propane and iso-butane and is non ozone depleting as well as having minimal global warming potential. The web site of an Australian manufacturer of hydrocarbon refrigerants (www.hychill.com.au) claims there has not been a case of a fire due to escaping refrigerant but we all know of fires due to ruptured tanks or fuel lines. The web site has a comprehensive article on charging a system, including the recommended amount of HR12 refrigerant for the Silver Shadow (475 g) ! While R134A (tetrafluoroethane) is preferable to R12 (Freon) it is still toxic with a high Global Warming Potential and will be phased out for all new cars in the EU from 2011. Most concern about hydrocarbon refrigerants seems to be coming from the fluorocarbon manufacturers. My advice remains the same as previously. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 1588 Registered: 4-2003 |
Now we have heard it all. Let's ban Spray Fresh and save the planet $42 billion on exploding airconditioners. BO Air Fresh or Air Conditioner.jpg  | ||
| Paul Yorke Prolific User Username: paul_yorke Post Number: 279 Registered: 6-2006 |
Gus's advice is very important. It is quite technical but don't be tempted to ignore it. Many R12 systems have been ruined by air CON 'engineers' just filling them up with R134a and not flushing the old oil out and changing it, or they will tell you they are adding a 'special oil' that works with both. Mobile engineers are especially good at doing this because it's easy money just to drain and re-gas. It will be lovely and cold as he gives you the bill, but a few months down the line you will end up with a nightmare! Always get the existing gas / oil checked. Also, as a warning to anybody with cars that have been imported. Don't rely on a sticker saying that the system has been RETROFITTED WITH R124a. I know for a fact that some dealers will just put a sticker on a car to get it through customs. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 1589 Registered: 4-2003 |
Quote: ______________________ Mobile engineers are especially good at doing this because it's easy money just to drain and re-gas. ______________________ Not in this country. There are laws. If he calls himself an engineer, ask to see his University degree. | ||
| Jeffrey McCarthy Frequent User Username: jefmac2003 Post Number: 99 Registered: 5-2007 |
I'll definitely check on the oil and the procedures he intends to use. Is purging the old oil a complicated procedure or do 'some' aircon techs just omit to do it because it's time consuming ? The car is an Australian Delivery by the way and although I don't have any records relating to aircon work there are stickers from 'Ken Green Air Con' in Sydney with a 1980s phone number. (Message edited by jefmac2003 on 15 February 2009) | ||
| Gus Brogden Experienced User Username: gus Post Number: 23 Registered: 2-2008 |
When retrofitting from R12 to 134a, use 90% or less 134 than the stated charge of R12. DO NOT charge to a completely clear sight glass. The condensing pressure should correspond to a temperature of no more than 30 degrees farenheit with a good fan blowing over the condenser. (Use a pressure/temperature chart for 134a). Dont use "drop in refrigerants" that are purchased at auto part stores in little cans unless you know EXACTLY what you are doing. They cool, but they dont mix with existing refrigerants, and they can do bad things and void warranty. Manufacturers may only honour warranty if you use refrigerants that they approve. Recover refrigerants, repair leaks, evacuate and recharge properly according to the chemical you are using. Some refrigerants are "near azeotropic" mixtures that must be charged as a liquid. If you are not qualified, find someone who is gov't qualified that you can trust. Remember Gay-Lussac's law and Dalton's Law. These are pressure vessels! | ||
| Bill Coburn Moderator Username: bill_coburn Post Number: 1079 Registered: 4-2003 |
Gosh I have and Richard does when he is here, an aircon man who I simply say the thing does this and this and he fixes it. I just realise how lucky we are! | ||
| John Kilkenny Frequent User Username: john_kilkenny Post Number: 74 Registered: 6-2005 |
I think most of us just go to the aircon man and my aircon man recommended HR12. Another advantage of a hydrocarbon refrigerant is that no flushing or oil changes are generally required when converting from R12 or R134A. A short description of the charging process for HR12 is given at http://www.hychill.com.au/pdf/recproce.pdf My Shadow SRH1405 has been using it for nearly two years with no problem. | ||
| Paul Yorke Prolific User Username: paul_yorke Post Number: 280 Registered: 6-2006 |
Jeffery, it's not difficult, but is time consuming as you may guess. Removing and draining the compressor is quite easy on our cars, but on other makes it can be a right pain in the . . . Flushing the pipes with air and a solvent is quite straight forward. Richard - "Not in this country. There are laws." It must be great to live somewhere where everybody is completely honest - I'm surprised they have laws at all. Do you have police and law courts there? They must have an easy life  Bill - you have the luxury of knowledge, as John says - most people just go to the air con man. :/ | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 802 Registered: 9-2004 |
John,yes the oil in 134a will give a fire but not a fire ball as the HR12 will with catastrophic results. To what degree this concerns you is an individual matter. However if say, the flexi hoses were not renewed when a change to HR12 and a failure occured causing loss of car etc, would the insurance pay or would the person or persons who recommended the HR12 be liable,instead of using 134a with new flexi hoses etc in the first place. There are many RR fires that leave no trace of the cause Hummmm!!!!!!!! (Message edited by pat lockyer on 16 February 2009) | ||
| Jeffrey McCarthy Frequent User Username: jefmac2003 Post Number: 100 Registered: 5-2007 |
Paul, When you say "removing and draining" does this mean that it has to be removed in order to drain it properly, or just that if you need to remove it for some other reason it's not that difficult to do ? (Message edited by jefmac2003 on 16 February 2009) | ||
| Mark Aldridge New User Username: mark_aldridge Post Number: 3 Registered: 10-2008 |
I have used drop in gas RS24 otherwise Isceon 49or R413a as a drop in replacement for R12. I understand that this has been used as a propellant in fire extinguishers! This is available easily in the UK and I have used it for some years on old Mercs,my Rolls Shadow and the Bentley 8 with no apparent ill efects. Mark | ||
| Paul Yorke Prolific User Username: paul_yorke Post Number: 281 Registered: 6-2006 |
Jeffery, if changing gasses to 134a , yes I'd take the compressor off and drain it, then change to a PAG oil. R-R recommend usong a poly Ester oil which can be used with 134a but mixes with the old R12 Mineral oils. Problems can arise later when somebody then tops up the R134A and assumes that it has a PAG oil and adds more of that to the system. Also early receiver driers use a descant which was designed to dry R12 not 134a, so I'd change that as well if in doubt or it is old. Mark - I've also used 413a with good results. | ||
| John Wright Unregistered guest Posted From: 203.206.241.243 |
If you do have problems with the compressor it is generally the seals or bearings that wear. In the Shadow II the air conditioning is used all the time the system is working, either for hot or cold air so it is more prone to problems than on the earlier cars. In my ShadowII I converted to a later compressor as used on the later series Spirits and found this lowered head pressure and increased compressor life enormously. If you need to replace the compressor I suggest you speak to Steve Sparks at NBS Services in Geebung Queensland.(07) 3865-6032 It will mean that you will need different brackets but the system will work much more efficiently with the new gas. Steve has the brackets you will need in stock. (Message approved by david_gore) | ||
| David Gore Moderator Username: david_gore Post Number: 863 Registered: 4-2003 |
Hi John, My apologies for the delay in releasing your post from last Friday - have been away without internet access. Regards David | ||
| Gus Brogden Experienced User Username: gus Post Number: 24 Registered: 2-2008 |
Back to HR12. It is a 50/50 mixture of propane and isobutane. Both are excellent refrigerants by themselves, and this mixture has a refrigeration effect similar to a 134 or 12 system. In servicing, you are dealing with a very flamable mixture so I would vent the vacuum pump to fresh air. I hear people have "topped up" this mixture on leaky systems with propane only. Bad move. Propane by itself has a similar condensing pressure to R22. With a rich R290 (propane) mixture on a hot day you could have condensing pressures well in excess of 400 psi., not to mention the change in evaporator, STV, and TXV performance. R290 refrigerant will also have considerably less moisture than what's in your barbeque tank. HR12 would be a "near azeotrope" mixture, and on a small leak the lower boiling point refrigerant (isobutane)would would be the one to mostly escape first, leaving a mixture richer in propane. Adding more propane would give you cooling, but the system suffers. If one was running straight propane, one might as well run straight R22, but an R12 or 134a compressor doesnt have the volumetric efficiency for it. With a system containing a blend like this, in the event of a leak, it is always prudent to reclaim the old refrigerant and use a new charge. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 1590 Registered: 4-2003 |
Perhaps I have been too flippant on this subject, and I apologise. The gist of my message is only to find a good shop and to trust them. They will choose the optimum refrigerant and not mess around with questionable oil mixes, with quick-fixes, or with reused refrigerant where inappropriate. Of course, do call around and ask before choosing a shop which prefers any particular refrigerant type which suits your own inclination, but I do suggest that to impose a refrigerant type on a shop would be folly. HR12 does sound attractive on all counts. For the records and interest, sure it is important to log what has been done and to understand it. Given that it has been virtually impossible to sell any car without refrigeration for decades, it is no surprise that the shops are well equipped to do any job properly. My own experiences have been non-events. Using R134a in our T since the 1980s has been trouble-free. The last recharge was around 1992 for a leaky STV, and I can safely claim that it still produces the same incredible volumes of cold air on demand. The guy was unfussed about whether to fit a new STV or to fit a pressure switch to cycle the compressor clutch so I left it. Today, I would prefer a cycling clutch if the shop agreed. My Turbo R has been fine on R134a for a decade, and of course its clutch has been programmed to cycle since new. I do hold an industrial and automotive refrigeration certificate myself, from 1981 in Central Queensland, but it has no doubt completely lapsed. I did it partly for fun. Mainly it allowed me as the designer to commission unrelated electrical power and control systems in cooled equipment rooms, but only when accompanied by a tradesman. Otherwise, I was to be booted off site by the unions. That refrigeration mechanics are heavily regulated in Australia, and that there are stiff penalties against DIY und unlicensed work, has good and bad aspects. Fortunately there is plenty of competition to keep prices fair. That the professionals risk heavy penalties for skimping seems to have had the benefit of self-regulation, as a shop is obliged to undertake work to a safe minimum standard. They have no incentive to use bogus labels or to do illegal work. The shops adhere to this in their best interests. Call it a cartel of mechanics hiding behind stiff regulations if you wish, but at least the quality is all but assured. Incidentally, shops become rather difficult when presented with a vehicle, boat or home heat pump whose refrigeration needs recharging after a DIYer has obviously vented it to do some related or unrelated mechanical work. Best plan it with him so he may prepare the system prior to doing your own work. We are rather sensitive about ozone depletion, and it explains why Australia leads the world on CFC rationalisation. One peripheral outcome is that Australia has practically only one worldwide dominant standard - UV protection in sunscreens. If you buy sunscreen in Nepal, the US, Switzerland or anywhere, it quotes UV protection to Australian Standards. We were rather upset when certain Europeans tried to argue against the 2000 Olympics choice of Sydney, citing that the ozone depletion was too much a risk for world athletes. It came up again in the UK press last month with the Australian Open, with the UK media claiming that Australia is too hot and too UV-dangerous to hold any world sporting event. Our popular laws are heavy when it comes to safety, ozone, CFCs and such things: there is a bloke in Victoria facing a long gaol term for using an angle grinder in the bush last week, starting a fire which destroyed a town. A shop will turn you away if you, as a customer, ask for less than the minimum. For example, a shop will not hear of changing refrigerant types without changing the desiccator and oil, and they are unusually uncompromising on oil types, purging, sweeping and the rest. The shops I know will only take on a new customer on the condition that the starting point assumes that oils and refrigerants are unknown, suspect, and need of being worked from scratch. Drop-in refrigerant doses ? Leave that to the used car lots if they dare losing their licences. As to retrofitting a Sanden compressor as on a 20000-series SZ and later, I asked the bloke in passing when at the shop last August buying somthing else. He rather turned his nose up at that as being only of marginal merit. There are plenty of Harrison/Delphi/Delco/Frigidaire/GM compressors out there, and the compressors on our cars have serious overcapacity in any case. However, if going brand new, it may be worthwhile if you are prepared to have brackets, fittings and drive belts set up. Sanden can be contacted to find a preferred outlet and service agent. http://www.sanden.com.au/english/environment/report2008/pdf/P46_47.pdf Sanden International (Australia) Pty. Ltd. 54 Allingham Street, Condell Park New South Wales 2200 Australia Telephone: +61-2-9791-0999 Incidentally, Sanden, a Japanese company, has a venture with BEHR of Germany, mainly supplying to Honda and European plants in China. BEHR, of course, supplies coolant radiators for SZs as OEM equipment. Sunscreen from a Swiss pharmacy:  | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 1593 Registered: 4-2003 |
For information on the Sanden 510, and its replacement Sanden 709 (SD709), standard for 20000-series SZs and possible retrofits to earlier cars, see: http://rrtechnical.info/sz/sz87/sanden7series.pdf Either the 510 or 709 fits later SZs exactly, but the 709 is better. The 709 is offered by Sanden, the SD7-series model SD709, and there are also Chinese copies at very good prices. The correct twin-groove V-belt drive flange is on standard offer. An adventurous shop may update even further, and go for a variable-displacement type like a Sanden SDV-series - no connection with the term suction throttling valve STV. The SD7V16 is one of the SDV-series. 54000-Series SZs have the SD7V16. That's kind of like having a STV or its early SZ cousin the POAST valve built-in, but it is usefully more efficient. The disadvatage of an internally-controlled variable-displacement SDV-type is during system diagnosis, when Crewe recommends fitting a fixed-displacement SD709 for the duration of diagnosis. RT. | ||
| Jeffrey McCarthy Prolific User Username: jefmac2003 Post Number: 101 Registered: 5-2007 |
Okay - I got the car re-gassed yesterday. New hoses, new valves,new o-rings, new receiver/dryer. It appears to work well. The gas has a flourescent dye in it so I can check for any missed leaks with a black light. I explained the oil story to the guy and (after he'd done the work!) he told me that the oil that was already in there was compatible. Being the anxious type I decided to double check this with the Aircon guy that Robert Chapman uses in Melbourne. He assured me that the Shadow system has a sump for the oil which ensured lubrication as opposed to certain other systems which depended entirely on mixing the oil with the refrigerant: something that happens on the Shadows but to a lesser degree and with a lesser degree of importance. We went over everything the guy in Albury had done and he assured me that it was all correct and there was no problem with the old oil. In fact he said it was better to leave it alone and that PAG oil was definitely not the go for this compressor. Which was something of a relief. Is it possible that with Australia's stringent bureaucratc standards that our aircon systems were a modification to meet Australian delivery requirements? Curiouser and curiouser... I guess I'll find out soon enough what the story is if the compressor seizes ! Cheers - and thanks for the informative discussion. Jeff | ||
| Gus Brogden Experienced User Username: gus Post Number: 25 Registered: 2-2008 |
Hey Jeff, what refrigerant did they put in? | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 803 Registered: 9-2004 |
Being compatable with that oil I would have thought it would be HR12,the mobile fire ball stuff, if it caught fire on the move! Hope I am wrong though! | ||
| Gus Brogden Experienced User Username: gus Post Number: 26 Registered: 2-2008 |
The only thing that bothers me about propane based refrigerants in mobile AC, is what could happen in the event of a front end collision where the condenser gets crushed. However, I am not knocking propane (R290). I think it is an excellent, cheap, non ozone depleting refrigerant. It has been used in europe in stationary systems for years. I went through my apprenticeship using R12, 22, 502, and ammonia. I cant count the refrigerants and blends out there today. Their system and oil compatability can be challenging. You can no longer take a pressure/temperature reading and be sure of what you are dealing with. It would be nice to see industry get it together and get rid of their "interim blends" and find green refrigerants that are safe, non ozone depleting and dont contribute to global warming. | ||
| Jeffrey McCarthy Prolific User Username: jefmac2003 Post Number: 102 Registered: 5-2007 |
Gus - the refrigerant is 134a (I assume there should be an R there as well but it's not on the handwritten label) Paul - The car is an Australian delivery and has previously had work done on it by "Ken GOLD - Rolls Royce and Bently Air Con. specialists Sydney" according to the old labels (not Ken Green as I'd previously written) John - The Aircon man I spoke to was 'the boss' at BOLD auto-electrics in Box Hill as you suggested - I would have gone to him in the first place but couldn't find the time (and extra cash) to go to Melbourne for a couple of days. When I go down there later this year I'll get Bob Chapman to do a service (the radiator hoses will be 2-years old in November) and I'll book the car in to Bolds for a check on everything. Incidentally, my system doesn't have a sight glass - I read somewhere in the forum that this might indicate that one of the components might be later than factory - where would it be found if it were there? Cheers, Jeff | ||
| John Kilkenny Frequent User Username: john_kilkenny Post Number: 75 Registered: 6-2005 |
Jeffrey, I would guess that your aircon had previously contained R134A so the refill with R134A would be logical. In my case the old refrigerant was R12 so it was simpler to replace it with HR12, as no flushing or oil changes were then required. If present, the sight glass is at the top of the receiver/drier but it is not unusual for a R134A system to be without one. Regards, John | ||
| Gus Brogden Experienced User Username: gus Post Number: 44 Registered: 2-2008 |
A word of advice to the wise out there who wish to "fix" their AC on their cars by installing these 'off the shelf' recharge kits. Dalton's Law Of Partial Pressures states that if two different gases occupy an enclosed space, they will exert a pressure as if they occupy the space alone. Which means to say, if an unevecuated system gets a different gas thrown in on top of the existing one, you start having pressure issues. I have seen many times where compressors have failed after it was fixed "in buddy's driveway". Proper evacuation removes all moisture and non-condensibles, leaving you with a system that's ready to charge. Dumping 'off the shelf' little cans on top of a system that is full of something else (albeit at neutral pressure) is asking for trouble. Excessive head pressure is asking for failure. I have never met anyone who bought these 'off the shelf' kits who actually own a vacuum pump and a set of gauges, nor would they know what to do with them if they did. Bottom line is, if you are not 100% sure of what you are doing, spend a hundred bux and get it done right. | ||
| Bill Payne Experienced User Username: wimpy Post Number: 17 Registered: 1-2007 |
Do these cars have an orifice tube? If so, that would need to be replaced. My limousines always get a new receiver dryer and orifice tube when we do the bi-annual evacuation, vacuum and recharge. | ||
| Jan Forrest Prolific User Username: got_one Post Number: 141 Registered: 1-2008 |
Sorry for re-opening an old thread, but I have a question regarding the working of the STV. During the recent heatwave in the UK (equivalent to a quite cool winter in Central Australia  ) the air con has ceased to blow anything other than warmish air. The electromagnetic clutch on the compressor always engages so I assume that the refrigerant level must be adequate, but no part of the system sees a temperature drop. I've watched the STV while switching the air con on and off, but it never so much as twitches! Could it have failed and thereby caused my discomfort during the current unseasonable weather? I might add that the system has not been recharged for over two years and I cannot recall which refrigerant (or lubricant) was used at the time, although I was assured that a flourescent dye was included to show up any leaks. BTW: does the dye normally flouresce in visible or UV light? | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2167 Registered: 4-2003 |
Jan, You car does not have a low-refrigerant cutoff, so the compressor will simply work continuously in vain if low, with the STV wide open. It sounds as if you are low on refrigerant. It is time for a service in any case by now. You will only see the dye for a short while after gas escapes, and it will be gone some days after gas stops escaping. Whilst the dye is vaguely visible in daylight, you can only see it positively with a UV lamp. A service shop will tell you all in a few minutes. The shop will attach a gauge to the system and give you an instant statement on the charge level, and before you commit to a service you will have a quotation. RT. | ||
| Jan Forrest Prolific User Username: got_one Post Number: 142 Registered: 1-2008 |
Thanks for the quick response Richard. I'll take The Old Girl in for an aircon checkup ASAP (subject to my temporarily limited finances). | ||
| John Kilkenny Prolific User Username: john_kilkenny Post Number: 103 Registered: 6-2005 |
Jan, The system should retain gas for longer than two years. If the aircon shop determines that the STV is leaking or otherwise faulty it is worthwhile scrapping it in favour of a simple temperature switch to cycle the compressor clutch. This is a cheaper and more efficient solution. | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 615 Registered: 6-2006 |
Jan - would like to add: Running the compressor with low or no gas will damage it, so disconnect the clutch to prevent it being turned on accidentally. Shadow II onward have a low pressure sensor. The dye needs UV light to be seen clearly. The dye is in the oil not the gas, so if the leak allows any oil out (95% of leaks do) , the dye will be there for ages( years sometimes if the engine is not cleaned or used much ) so it is much better at showing up slow leaks that gas detectors will miss on the day the system is filled. It is important that the dye is cleaned off after any leaks are repaired to stop any confusion in the future. It's hard to remove it thoroughly though. (steam cleaning.Brake cleaner, Carb cleaner - not just a wipe) (Cheap UV torches are available from ebay. Take a look on a dark night or blacked out garage) If your leak is due to rubber hose failure or R134a being used with the original hoses, the gas may permeate the rubber hose but the oil has too large a molecular size to escape, so it's possible no sign of dye will be seen on them. | ||
| Jan Forrest Prolific User Username: got_one Post Number: 143 Registered: 1-2008 |
Thanks again. I've got a couple of UV lamps, so I'll have a look using one of them later this evening. I think it might have been refilled with R134a refrigerant as the compressor has a sticker on it indicating that it was 'remanufactured' some time between 2000 and 2004 (it's a bit vague on the actual year) and much of the system is a little cleaner than I would expect for a 34 year old one. | ||
| Dave Puttock New User Username: ariel Post Number: 5 Registered: 5-2010 |
I am rebuilding the aircon from scratch having had the evaporator out of my SS1 Does anyone have a list of the sizes for all the HBNR (green) o-rings that would be needed to equip for R134a. Its rather difficult to judge original size from the hardened ones I took off. | ||
| Peter Talbot Experienced User Username: squerryes Post Number: 24 Registered: 7-2010 |
The air con on my 1986 Silver Spirit has failed yet again - total lack of gas. Seems like I have a slow or pinhole type leak somewhere which is proving a right !!**!! to find. Already had 2x re-gas and new compressor fitted but still no joy. Charles at Ghost Motors is determining and will sort the source of the gas leakage but I should welcome any advice. Don't consider this a DIY job, as I have no experience in this field. Peter | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 633 Registered: 6-2006 |
Peter, Have they added UV dye. If not, they must. If they have and there are NO signs of it leaking anywhere, the only really hidden place for leaks is in the evaporator and dash pipes- you may bet lucky and see dye residue coming from the evaporator drain tube under the car.. Also look at the front of the compressor inside the pulley. Do the checking in the dark of night if necessary. | ||
| Peter Talbot Experienced User Username: squerryes Post Number: 26 Registered: 7-2010 |
Paul Thanks your response. I think the problem in locating this gas leak is that it is real slow - everything works just fine for a couple of months then the air con packs in. Will check if UV dye added and report back. Peter | ||
| Peter Talbot Experienced User Username: squerryes Post Number: 38 Registered: 7-2010 |
Ghost Motors have sorted out my air con, replacing 2 defective hoses. I like the air con now working well, didn't like the cost of the 2 hoses which should have been gold plated at the price!! Peter | ||
| Jan Forrest Prolific User Username: got_one Post Number: 151 Registered: 1-2008 |
I know it's a bit late now, but you might have been better to go to an 'ordinary' garage that also works on air con units. Other than the Imperial fittings of the hoses in question, they shouldn't be all that different to any other car fitted with an air con system. I seriously doubt that most parts are much different to American systems, many of which are still using BSF and BSP thread sizes under the AF banner. | ||
| Peter Talbot Experienced User Username: squerryes Post Number: 39 Registered: 7-2010 |
Jan Thanks for your comments, but I really have neither the time nor inclination to "shop around". Ghost Motors collect the car, fix the faults, do an inspection, service as required, top up anything that needs to be topped up, bring it back. Yes it's expensive, but it suits me fine for Charles at Ghost Motors to maintain my Spirit in A1 condition so all I have to do is to enjoy driving it. Regards Peter | ||
| Bill Coburn Moderator Username: bill_coburn Post Number: 1268 Registered: 4-2003 |
Peter/ It is always irksome to see this happen. A 1983 Spirit arrived here some months back with a very iffy starter. The new owner innocently popped the car into a local electrical shop and they replaced the unit with a genuine new/old Lucas one for $2880!!!!.. A modern Nippondenso would have cost him $600 max! Sounds like you got parts from a dealer. These people are bound by contract to only sell genuine Factory supplied parts even though it may be obvious that the same items could be bought in the shop next door. Recently I needed the button switch for the parking brake warning light on the Spur. The local dealer had one for $130, Flying Spares, $60 and Farnell's in Melbourne $10.30 - for the same switch! This is no reflection on the Company which has bought these spares, stores, catalogues, maintains and despatches them which all costs money for parts which may never sell! They are not running a charity! But if you have the time and patience you can find these savings. And then recently I had made up a replacement high pressure hose for the power steering on a Shadow - $130. A new one from the dealer $270. A hose after all is a hose. The problem of ends is simply overcome by hacking the old one off and welding it to the new one! | ||
| Jan Forrest Prolific User Username: got_one Post Number: 152 Registered: 1-2008 |
I recently had to replace three of the door relays that control the windows. The 'official replacements' (although slightly different to the true original ones) are GBP10 each plus postage and tax. A local electronics stockist sold me 5 for just under GBP10 and they are rated a little higher than the others! I fitted them and the windows now all work again and I have two spare relays ready for when more of them eventually give up the ghost. There are many other components or even whole assemblies available that are as good, if not better, than 'official' RR/B replacements that can save us even more money. Don't forget that it's been decades since the Shadows & Spirits went out of production, but automotive technology hasn't stood still. The ethos of Crewe was always to use the best proven technology in the cars no matter what the source. Should we be any different? | ||
| Peter Talbot Experienced User Username: squerryes Post Number: 40 Registered: 7-2010 |
Bill & Jan With respect, I think you each miss the point of my previous posting to this Forum. Among other things, I own and control a private International Trading Group, which takes up most of my time. Running and driving a 1986 RR Spirit is one of my few relaxations and I require it be maintained in A1 condition at all times. Ghost Motor Works Ltd. (www.ghostmotors.co.uk)are the premier independent RR Specialists in the South East of the UK and not far away from my home in Westerham. If I've got a problem/need a service/whatever, Ghost Motors just sort/fix it. Time to me is a precious commodity to be conserved so whilst I might whinge a bit as to the invoices I receive, these pale into insignificance compared with my pleasure in knowing my Spirit is in absolute A1 mechanical and bodywork condition. Peter | ||
| Bill Coburn Moderator Username: bill_coburn Post Number: 1272 Registered: 4-2003 |
Well Peter, also with respect. There are two types of owners of Rolls-Royce cars, those that can afford them and those that can't. The latter group are by far the majority. I could reel off many stories of gross shock when owners were confronted with huge bills for repairs of their cars. For people who can meet these costs without difficulty, such expenses are accepted as part of the enjoyment of owning these cars. I gather you fall into this category. But if I may add, you are unusual in that you take an obvious interest in what is involved in keeping your car car on the road, which is just great. So many times I have seen owner's eyes glaze over the moment you open the bonnet to explain some repair. Most repairers I note now don't bother. There is of course the owner who buys the car with the impression that he is improving his status in his own eyes and/or the eyes of others and greatly resents the bills that come in when he takes his car to 'my man'. 'My man' is then seen by the owner as some money sucking leech and no amount of explanation as to what is involved with maintaining these cars will be entertained! Lastly, there is the large group of impoverished owners who manage as best they can to keep their cars running by doing their own repairs and hunting around for the lowest price for parts. These people even to this day are considered by some Club members as simply 'not really the right sort of chaps who should be allowed to own these cars'. It is the chaps however that have really spawned this Forum, the Technical Library and Tee One Topics!!! And long may it continue I say. If it were not for the likes of us if I can be permitted that collective term, far more cars would be in the wreckers' yards and the only remaining examples would be pristine museum pieces owned by the very wealthy and securely planted in a museum. Just recently a prominent supplier and wrecker of our cars in the UK published a list of their holdings some of which were apparently very usable cars but nevertheless labelled 'no longer economical to maintain!!!' To me that is a bit like putting your dog down because it needs to go to the vet! I enjoy my cars. They drive me to distraction but I struggle on with help from people such as Paul and Jan and Lawrie and Richard and...... My favourite analogy for the vagries of these chariots, is the annual confirdential report on a young aspiring officer to the effect that 'his men follow him out of sheer curiosity as to what he will do next!!'. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2186 Registered: 4-2003 |
It seems that it is time to shut down the Forum and leave it all to the Ghosts. They might as well close the Technical Library while they are at it. Thanks for the plug, Peter. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2188 Registered: 4-2003 |
And Jan, This refers mainly to SZ cars with their Bosch relays. SYs are not so critical. There should be no problem using those cheaper relays in general, but do take care. Sure, you can buy them for as little as $2 each if you don’t mind the plastic appearance. However, they are not necessarily suitable in all applications on these cars, as most compatible relays have a bipolar suppressor rather than a freewheel diode. To be succinct, with a suppressor, the relay coil voltage spikes at around -25V when the coil de-energises. That can damage some electronically-driven (solid state) circuits like the climate control, ABS, cruise control, Turbo control, ignition and fuel injection. The original Bosch relays with the internal freewheel diode limit the spikes to -0.7V, and are safe when driven by solid state circuits. Be safe ! If contemplating non-standard relays, it is advisable to fit a freewheel diode across the coil terminals underneath the socket. Once that’s done, all relays of the same pattern (pinouts 30, 85, 86, 87 and 87a) are safe. Freewheel diodes set you back 5¢ each at Jaycar (EM513/1N4007 etc). Also, by the way, the aircon and power steering hoses are all bog-standard generic items with industry-standard connectors and threads. One time around 1984, the power steering high-pressure hose on our T-Series blew out on the harbour bridge. I flexed the muscles and continued the drive with unbearably-heavy steering down to Woolloomooloo and spotted the first garage with Steering somewhere on the sign. Within 30 minutes it was all done with a new hose made to pattern, connectors and all. It sure saved hours and hours time compared to booking the car into York Motors for a fix, then catching taxis all over the place. RT. | ||
| Jan Forrest Prolific User Username: got_one Post Number: 154 Registered: 1-2008 |
Having had the opportunity to strip down one of these relays (OK, it fell apart as I was removing it) I can say that they are actually momentary on/off dual pole switches. As such there is no coil to cause any back EMF when they are de-energised. However it could be useful to add a small capacitor across one side of it to eliminate arcing. It wasn't just the price that attracted me to the ones I've fitted though. The original Burgess switches have become unavailable from new, and the closest I can find are only sold by RS Spares at a little more than GBP2 (plus postage and tax). Unfortunately RS Spares will only sell them for delivery if you have a credit card and don't accept debit cards. Also their nearest branch is over 40 miles away in the centre of one of the largest cities in South Yorkshire. Even in the Toyota that's nearly 3 gallons of fuel and half a day negotiating city centre traffic. No thanks! As for the air con hoses I mentioned US sizes because the compressor on The Old Girl is an American one that was rebuilt some time after 2000. The plate is a little vague on this subject. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2193 Registered: 4-2003 |
Jan, you must live miles from civilisation ! Here we can buy suitable relays at Repco, Supercheap, Autopro, Autobarn, Jaycar and elsewhere. In Switzerland and Germany I buy them at the local supermarket in the Auto-Ersatzteile & Zubehör section. The genuine ones are sometimes available from Bosch for around $20, but I have heard that Bosch is going plastic-only anyhow. The same applies to microswitches - you can buy them anywhere on this earth. You say
On reading your post and its referring to door relays, I now realise that you must mean microswitches as you refer to Burgess (Saia-Burgess). These exact microswitches are not purely meant for automotive use, as they have billions of applications all over the place from space rockets to washing machines. Any electrician should have a few in the bottom of his toolbox next to the cable ties. Mind you, there is any number of brands such as Omron and even Tyco which are better and made to the same international and military standard as the Burgess ones. Just be sure that they are DC rated, as AC-rated microswitches will not last long in a DC application. The matters of micriswitches and relays are covered in the Technical Library under the Slow Windows fix article. When referring indeed to the generic relays in our cars, they are not solid state relays. Of course they have coils. The coil is that wiry layer wrapped around the magnetic post thingo. Do I need to show a picture ? You can see the freewheel diode inside the can easily too. RT. | ||
| Peter Talbot Experienced User Username: squerryes Post Number: 43 Registered: 7-2010 |
I seem to have been instrumental in veering this topic way off course, which was not my intent. So: my apologies all round. Peter | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 646 Registered: 6-2006 |
Possibly Jans year had non-diode relays - but definitely had a coil The Bosch plastic relays are hermetically sealed and in my experience MUCH more reliable and worth the extra over the cheap and cheerful ones. Quote: "That *can* damage some electronically-driven (solid state) circuits like the climate control, ABS, cruise control, Turbo control, ignition and fuel injection. " Non diode relays *WILL* fry your chips. | ||
| Jan Forrest Prolific User Username: got_one Post Number: 155 Registered: 1-2008 |
My apologies: The door window and central locking switches are definitely micro-switches and not relays. Even so the prices I quoted, and the lack of direct replacements, are still correct - at least in Blighty. Obviously I made sure that the ones I bought were rated for a DC current comfortably over the current likely to be seen through them. The problem stems from the original switches having 2 screw terminals and one push fit. Similar switches can be obtained, but the terminal lengths are considerably greater than original and would compromise the already minimal clearance between themselves and the bus bars that join pairs of switches. As has been stated; some people have more money than time so they are happy to just drop the car into a main dealer/repairer and have all original parts fitted no matter the cost. Some of us cannot afford this and/or prefer to get our hands a little grubby in pursuit of keeping them going long past their 'sell-by-date'. Hell, some of us even enjoy the process! I know I do despite the aches and pains of my arthritis and angina. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2195 Registered: 4-2003 |
Jan, As implied, just ask your local appliance shop or electrician for a few. Certainly any electrical trades supplier will have lots to choose from. You could just buy a dozen or so from RS or wherever and be done with it too. These ones are sold by Jaycar for $2.53+GST each. A rating as low as 10 at 250VAC is not suitable for the direct operation of windows as they derate to about 4A at 14VDC, but if the window relay mod has been done then they are fine. Best find a microswitch rated for at least 16A at 250VAC.  In the UK, at RS Compnents (a global outfit by the way with outlets in Australia too), the Omron microswitch named V3 microswitch SPDT 16A, long lever, will do at a pinch. Go to: http://uk.rs-online.com/web/ and put: V3 microswitch SPDT 16A, long lever in the Find box at the top left to see the page of the catalogue. It is priced at GBP1.68 for very small quantities and of course you can mail order. Rated at 16A at 250VAC, it is only just acceptable when derated for DC to 8A. An 8A DC rating is OK in most instances, but ideal is the Omron V-21-1C6 rated 21A at 250VAC, and 18 A at 14VDC. Note that the relay type in the top right of the picture in this post may be used with or without the lever, as the lever unclips. Incidentally, a tip for those with an SZ: the .door switches for the lighting comprise an IP50 subminiature microswitch inside the door at the latch. They last well, but are subjected to grime, moisture and high air flow, hence the IP50. They are annoying to replace as the entire door latching mechanism must be removed from inside the door cavity. The switch may be replaced by a standard microswitch with its lever fitted and with an IP65 cover, and it screws into place perfectly despite being larger. RT. |
