RichardC 124 Posted May 25, 2020 Report Share Posted May 25, 2020 My 400 has just broken down and I've just come back home on the back of a recovery truck. A great way to spend a Bank Holiday afternoon! Up to this moment the car has been running fine, apart from the air-con not blowing cold again (for the third time in the past two years). On the motorway, I hear a whining noise for a few seconds, the engine stutters momentarily and the MIL light comes on for a short while and then goes back out. The car keeps on running, maybe with the power reduced a bit from normal, but then I notice that the battery charge light is on, so I know that something is definitely amiss. Luckily, I'm just about to pass a service station so I pull in there. By the time I'm parked up the engine hot light is on, I've lost some coolant and the power steering assistance is fading away. Looking at the engine, the auxiliary drive belt is off the supercharger pulley (which is turning freely), so I pull it out of the engine. It has snapped completely and the whole inner surface is scorched and scuffed, like it has been running around a seized pulley. Does that seem likely? Maybe the alternator or air-con pump? My air-con has been temperamental ever since I've had the car, with multiple re-gases required despite no leak being found, so my money is on that being the culprit. Tomorrow's job is to investigate and hopefully fix it. Is it an feasible job for a DIY mechanic? Any tips would be appreciated. I'll certainly be needing to order a new belt and get some coolant. What sort of coolant should I be buying? If something has seized then I'll be a bit miffed as the car is just out of warranty. It is still due to have a few warranty repairs (supercharger oil seal weeping, plus a couple of trim niggles) done, but they have been on hold because of the lockdown. Maybe I can negotiate, especially if it is the air-con pump that has cause the problem I'll keep you all updated... 1 Quote Link to post Share on other sites
Bruss 577 Posted May 25, 2020 Report Share Posted May 25, 2020 Sorry to hear that. Quote Link to post Share on other sites
21gg 399 Posted May 25, 2020 Report Share Posted May 25, 2020 Ive had an aircon pump sieze and normally the ecu detects it and disengages the ac clutch. I reset the code and all you heard was a momentary squeak and it disengaged the compressor again. I would be suprised if it was that as the ac clutch would have to be seized aswell. How old is your car? If the pump has gone and you ha e to pay for it, dont get it from lotus! Quote Link to post Share on other sites
RichardC 124 Posted May 25, 2020 Author Report Share Posted May 25, 2020 Car is just over 3 years old, c27000 miles. It seems that any old OAT red antifreeze will do, so I'll go for Comma, as the Petronas Paraflu Up recommended in the service manual is expensive and hard to find. My dead 7pk2958 belt is made by Dayco, but there seem to be lots of Continental Contitech ones on ebay for reasonable prices, so I'll probably go for one of those. As for access, it seems to be an under-tray off job, but do you also need to remove the wheel arch liner? Quote Link to post Share on other sites
philcool 153 Posted May 25, 2020 Report Share Posted May 25, 2020 The A/C compressor has no oil sump and is cooled and lubricated by the returning refrigerant cool gas from the evaporator this also brings a mist of oil with it. If the compressor has been running short of refrigerant charge then it tends to overheat and be starved of oil so all manufacturers fit a low pressure switch in the system to cut out the compressor when the refrigerant charge becomes low. There can be operational reasons why the pressure can become low other than refrigerant loss. Defective expansion valve this is the valve that meters the refrigerant into the evaporator Iced up or dirty evaporator not usually common on cars Low air flow across the evaporator faulty fan blocked pollen filter. All A/C systems should shut off when the interior fan is turned off. So if you have been having trouble with the A/C system loosing refrigerant that can be very hard to find as it only holds approximately 700--900grams so only needs a small weep to loose it.sometimes you have to add fluorescent die to the system then run the system and look with an ultraviolet light at night. Anyway suspect the fault could be with the A/C compressor or clutch if it hasn't disengaged good luck a real shame on a cars that only done low milage 1 Quote Link to post Share on other sites
RichardC 124 Posted May 26, 2020 Author Report Share Posted May 26, 2020 Update: I've taken the under-tray and wheel-arch liner out to have a good look around. The only pulley that I can't turn by hand is the air-con pump: it moves just a jog but then feels solid, in either direction. Is that normal or does that mean that the air-con pump has seized? I reckon that I can just about replace the belt on my own, but if I do and the air-con pump is seized, then it will just shred itself again. Replacing the air-con pump looks very difficult. I'm stuck. Any suggestions would be very welcome. Quote Link to post Share on other sites
philcool 153 Posted May 26, 2020 Report Share Posted May 26, 2020 The air con pulley should spin freely as the clutch should not be engaged so should freewheel freely without turning the compressor so either the freewheel bearing has gone or the clutch has stuck in and the compressor could have seized. The clutches only move a millimeter or so induced by a circular electro magnet behind it around the compressor input shaft Quote Link to post Share on other sites
RichardC 124 Posted May 26, 2020 Author Report Share Posted May 26, 2020 It does sound like the air-con compressor & clutch are to blame then. Could them failing be a result of the ongoing gas loss issues that I've had ever since I bought the car, I wonder? I don't want to get the compressor replaced, either by myself or under warranty (it would have to be good will from Lotus, as it expired 2 months ago), only for me to keep having to have yearly re-gassing, or have the new compressor fail again. Air-con shouldn't be a subscription service - my mum's 2003 Totota RAV4's air-con works as good as new and has never needed anything doing to it! With my Evora it's been nothing but trouble. The compressor is the same as one from a modern Toyota RAV4, isn't it? And it seems that there is an access panel in the rear bulkhead that allows you to get at it: I was struggling to see how to get at it from below or above. Quote Link to post Share on other sites
21gg 399 Posted May 26, 2020 Report Share Posted May 26, 2020 If you have a look on the other lotus forum techwiki you can find the part numbers for the toyota and other reference numbers i found when my na evora compressor seized years ago. Quote Link to post Share on other sites
RichardC 124 Posted May 26, 2020 Author Report Share Posted May 26, 2020 Lotus Part Number A132E6349S Toyota/DENSO Part Number 8832042120 UAC Part number UAC CO 10856C FROM A USA TOYOTA RAV 4 3.5L V6 2006-2012 DeRoure suggest that there are now two different compressors for the Evora 400: one with PAG46 oil (for R134 refrigerant) and one with ND12 oil (for the newer R1234 refrigerant). I'm presuming that it is the same compressor, but with different oil in it. Not sure how I find out what refrigerant type is in my car: is there a sticker somewhere? If I end up buying a cheapo non-Lotus compressor (£250 vs £2500!), then it will be a PAG46/R134 version: can I just exchange the oil in the compressor if my car needs ND12 oil? Quote Link to post Share on other sites
21gg 399 Posted May 26, 2020 Report Share Posted May 26, 2020 Didnt know they changed them. Deroure notes in section 18.03 says R 1234YF introduced on EU cars from vin GH 21289 refer to service builtin 2016/21 Im sure they must do a non oem verion of the later type. You could always get yours refurbished. I dont know if its an option but could you run a smaller belt with the ac compresor removed while you to get yours rebuilt? Gav 1 Quote Link to post Share on other sites
RichardC 124 Posted May 27, 2020 Author Report Share Posted May 27, 2020 I can't find Service Bulletin 2016/21 online anywhere and I don't really understand those VIN formats: the numbers are nowhere near the number on my car. My 400 was built in late November 2016 and registered in March 2017. Anyway, it looks like the refill cap colour tell you what refrigerant your can has inside: blue for R134, black for R1234. I'll have to investigate: the air-con refill is behind the front wheel arch liner, I think? I'm really hoping that I can get a warranty fix on this, but as it is the car is undriveable and stranded a good two hours away from the dealer, so a temporary air-con compressor removal would at least get it back on the road and allow me to drive it to the dealer when this Covid thing is over. I've got no idea what length belt to buy to make that work though. Has anyone ever done an air-con delete on a 400? Quote Link to post Share on other sites
21gg 399 Posted May 27, 2020 Report Share Posted May 27, 2020 Richard, ive looked and i still have my old siezed compressor complete with working clutch. If its any help you can have the clutch off it if it gets you back on the road? What part of the country are you in? Gav Quote Link to post Share on other sites
RichardC 124 Posted May 27, 2020 Author Report Share Posted May 27, 2020 Thanks Gavin, that could come in handy. I'm not too far away from you: I'm in Merseyside. When you compressor seized, did you change it yourself or take it to the garage? Anyway, I'm done with working on the car for now as I'm due back at work tomorrow, in Yorkshire. With the car off the road, I'm having to take the train and stay over there for a few days. Quote Link to post Share on other sites
21gg 399 Posted May 27, 2020 Report Share Posted May 27, 2020 Im not that brave or handy, I got the dealer to do it! No problem, just give me a shout if you want it. The compressor is to heavy to post but may be able to post the clutch. Gavin Quote Link to post Share on other sites
au-yt 482 Posted May 27, 2020 Report Share Posted May 27, 2020 From what I can see the belt ribs don't appear to healthy, I had my belt changed earlier this year and kept the old one just to inspect it and there were sections where the belt was cracking up. but not as bad as yours. I cannot help but wonder what the actual age of the belts are when fitted at the factory new buying in bulk etc. Now LOTUS have a 4 year belt change in the maintenance schedule to the new gator type it will be interesting to see if there is a reduced incidence. Quote Link to post Share on other sites
RichardC 124 Posted May 27, 2020 Author Report Share Posted May 27, 2020 I think that the belt ribs are just damaged from being dragged around the seized pulley. The engine bay is full of little pieces of burnt rubber, with sticky burnt rubber in all the pulleys. Quote Link to post Share on other sites
Hangar 111 301 Posted May 27, 2020 Report Share Posted May 27, 2020 It's relatively easy to do on the Evora due to the access panel. Make sure you get it de-gassed before you do the job - there may well be residual in there at least. Also you need to find the source of your leak. As this could well be the cause of the seize - when all the oil disappears in the gas, the pump will seize eventually. @philcool is the man for air con knowledge Dave Quote Link to post Share on other sites
philcool 153 Posted May 27, 2020 Report Share Posted May 27, 2020 My S2 Exige has no sticker but the refrigerant and quantity is in the handbook as for the oil it's a little bit complicated with the new refrigerant https://www.denso-am.eu/media/corporate-news/2017/august-2017-newsletter-compressor-oil-and-refrigerant-mixing-old-and-new/ If it's got R134a in it and PAG46 oil I'd stick with that as the PAG oil will be around the hole system so not easey to change. I'm pumping out 960kg today enough for a thousand cars and 490L of oil 1 Quote Link to post Share on other sites
RichardC 124 Posted May 27, 2020 Author Report Share Posted May 27, 2020 1 hour ago, Hangar 111 said: It's relatively easy to do on the Evora due to the access panel. Make sure you get it de-gassed before you do the job - there may well be residual in there at least. Also you need to find the source of your leak. As this could well be the cause of the seize - when all the oil disappears in the gas, the pump will seize eventually. @philcool is the man for air con knowledge Dave I never knew about the access panel and was thinking that there's no way to do the job without taking the engine out! My Lotus dealer has tried to find the leak on a couple of occasions in the past but couldn't. All they could do was re-gas the system but it would stop working after 6-12 months. Air-con is a bit of a dark art. Maybe I could fit philcool's chiller from the picture above? It would squeeze on the back seat, surely, and should have enough reserve to keep me cool between annual services. 1 1 Quote Link to post Share on other sites
philcool 153 Posted May 27, 2020 Report Share Posted May 27, 2020 Each chiller is 6 mega watt plenty of cooling there only thing is the compressor is 1.2 Ton on its own As for finding leaks on car A/C can be a real pain might even be an over or under crimped hose so I feel your pain Quote Link to post Share on other sites
electro_boy 201 Posted May 28, 2020 Report Share Posted May 28, 2020 My AC failed last year while on a road trip in Spain and that took out the belt too. Lucky didn't drive too long and engine temps stayed normal so zero damage to the engine. I think the compressor seized and then the AC clutch also failed and did not disengage. I think thats what damaged the belt, engine trying to still spin but the AC pulley seized and a very confused belt not knowing whether it was coming or going. Richard, if you have no luck finding a local source for a cheaper AC compressor try giving ES Motorpsort a call. They had some in stock for considerably less than the Lotus RRP Quote Link to post Share on other sites
RichardC 124 Posted June 8, 2020 Author Report Share Posted June 8, 2020 On 27/05/2020 at 00:49, 21gg said: Didnt know they changed them. Deroure notes in section 18.03 says R 1234YF introduced on EU cars from vin GH 21289 refer to service builtin 2016/21 Im sure they must do a non oem verion of the later type. You could always get yours refurbished. I dont know if its an option but could you run a smaller belt with the ac compresor removed while you to get yours rebuilt? Gav My VIN ends in H H C 1 02xx. Which gives: H for 2017 model year. (G would be 2016) H for Hethel. C for RHD Other markets. (H would be LHD Motorsport) 1 for manual transmission. (2 would be automatic transmission) 02xx serial number. Not sure how GH 21289 fits into that series? Can anyone work out if I have R1234yr of R134a in my A/C system from the VIN? If not then I'll have to take out the front wheel-arch liner and have a look at the refill ports, and no doubt break or have to drill out those pesky clips that hold it in place... Quote Link to post Share on other sites
21gg 399 Posted June 8, 2020 Report Share Posted June 8, 2020 I would sumize that that as yours is 2017 H, ie after 2016 G, and as the buitin is dated 21/2016, that yours is the later type. You may be able just to pull the edge of the wheel arch liner enough to see? it may be easier to get yours rebuilt or see if a (my) failed old one could be rebuilt to the new spec seals/oil? That way its only one lot of labour to swap them over and the car isnt off the road unnessasarily? Gav Quote Link to post Share on other sites
Chillidoggy 4,340 Posted June 8, 2020 Report Share Posted June 8, 2020 I’m curious, is there not a pressure switch in the air con system that disengages the clutch when it senses low pressure? Quote Margate Exotics. Link to post Share on other sites
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