I believe my AC Compressor Pulley is loose.

[McElan]

I've just purchased a 1991 Lotus Elan and the first problem with it is that the AC will make a low but loud rumbling noise when it's turned on. Also, there is a noise coming from what I believe is the A/C Compressor pulley. The inside of the pulley wheel is loose and is able to move slightly back and forth and seems to be making the clanking noise while the car is idling. (Sounds like a heatshield vibrating against an exhaust) The wheel itself isn't wobbling or loose and the bolt seemed to be on at least handtight. It's just the inner part of the pulley has some side to side movement. (I've pointed in the photo of where it's loose). Would I be able to remove the A/C Compressor pulley and replace my current drive belt with the non A/C drive belt instead. Or if I remove the A/C Compressor pulley, would I be able to tighten it together or replace the pulley. I don't mind having no A/C as the noises coming from it are the loudest part of the car currently. I believe any of these would be the correct belt if I went along with the no A/C belt instead: Part Number: FVP 370K6, CONTINENTAL 370K6MK, DAYCO 5060370DR, CONTINENTAL 6PK948 from Rock Auto US.

I read up on the Belts page of the wiki and would replace the tensioner: (GATES T41027) and idler: (GATES T42001) But I'm having trouble finding a water pump from the wiki page that's in stock. I searched for the Isuzu 1991 Impulse water pump and found these two options available. US MOTOR WORKS US9220 and GMB 1401320.

Please correct me if I'm wrong about any of this. I'm extremely new and ready to learn about the Elan.

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[dapinky]

Hello and welcome to the madhouse that is LEC!

Firstly, I can't comment on your other post about the oil cooler as I have no idea if the Federal cars have exactly the same units "down there" as the UK cars, so I'll leave the specifics for someone who has done the work on theirs and knows which part(s) can be used/swapped......

...... that said, many years ago I replaced my (UK car) oil cooler with an off-the-shelf unit which required a couple of new brackets and a suitable 'housing' to deflect the airflow. I did it because mine was leaking and i had a trackday booked the next weekend and couldn't get a direct replacement. This was intended to be a temporary fix, BUT, it is still there and has never caused an issue.

If it is something you may be considering, and are going to replace the hoses anyway, then there is no issue with having whatever fittings you want on the radiator end of the hose.

Basically, I used a Setrab 210mm 19-row M22 radiator, associated fittings, (fir-tree type as I was doing it all in quick-time in my garage) and aeroquip hose.... I had a sheet of 1.2mm aluminium in the garage, so used that to fabricate a 'surround' and brackets, and it took about 4 hours to do.

If there is no rush, I'd suggest that my approach may not suit you at all!!!!! - certainly the parts can be got these days, but I don't know about the cost or availability.


Anyway, for this post, again I don't know what gets in the way on a Fed car, but one of mine has A/C - and I've never used it (or messed about with any parts of it). So, I can't help with how much play should be in the clutch unit of the compressor (if any) - someone else will be along shortly.

As for the parts you list, does this mean that you are looking to replace the cambelt/waterpump/idler/tensioner anyway as another job? None of those bits should need to be disturbed to deal with the A/C system - but if it is something that you want to do anyway, then be aware that there are some inconsistencies with the RA catalogue, and *some* waterpumps that they say are suitable, have a pulley with square teeth not rounded teeth...... of the two they currently have in stock, then I would go for the GMB item......

..... however, the main reason I use Rockauto is because it is quick and easy to order from them for delivery to the UK - you are clearly in a different position, as you would need delivery to USA, so there may well be other suppliers who can sort you out. I have used Summit Racing previously, and also JEGS - both have been very good, but maybe not quite as seamless as ordering from RA.......

[McElan]

Thank you for your insight. I see that SJ has an Oil cooler available, part number: SJ100K0001. Although I don't mind going the route you did and try to piece it all together with a Setrab radiator. It would definitely be cheaper and quicker. It seems that you've had your Setrab radiator for a while now and I assume you've used it on a couple track days with no issues? I would double check the current fittings/pieces but would you recommend the fir-tree type fittings again or go with something else if you had the time?

For the A/C, I was reading on the wikiLEC and it suggested to replace the cambelt/waterpump/idler/tensioner as a whole project, but if that is not required then I'll attempt to remove the A/C Compressor and replace the belt with the shorter belt labeled as #9 in the above diagram. I was reading a previous thread from a few years ago about someone else removing their A/C because they mainly drive with the top down anyways and it wasn't worth the hassle and price of repairing/replacing. Perhaps, it is a simple fix such as tightening something but having it off the engine anyways would make it simpler to assess.

[TorqueHorse]

Welcome to Elan ownership!
Whatever you do, please don't throw away the compressor! They can be rebuilt, and especially with the multi-ridged pulley that we have, they are rare to find in the wild, so rebuilding is easier that buying (usually).
You asked "... if I remove the A/C Compressor pulley, would I be able to tighten it together or replace the pulley. "
Hopefully! Taking it to an AC shop and they should be able to point you to a place that can evaluate and hopefully rebuild the compressor (the low rumble might be the compressor bearings going) and fix the pulley. You need a special puller to do the pulley and compressor bearings, so I took mine to a local shop and they did it. This is the place local to me https://aracparts.com/ hopefully you have someone like this near you.
FYI, you have the DKS13G compressor.

Or do the other option and delete the compressor and get a belt for just the PAS.

Also, you don't need to do a whole cam belt, water pump and tensioner service in order to just change that one belt.

[Simon_P]

The pulley where you have arrowed it is mounted on a fairly large diameter bearing which is mounted on the casing of the compressor it shouldn't wobble and shouldn't make any noise with the a/c off.
You can get a ch ch ch ch ch noise when the a/c is off and the clutch plate is stationary but rubbing.

The original R12 style compressor is relatively noisy - a slight rhythmic pulse to rrrrrrrrrrrrrrr

If the main pulley has play that suggests that the bearing has gone - if you remove the pulley you have done 90% of the job as it is mounted on the bearing - you can buy the bearing separately.

[McElan]

My apologies, I was mixing up the cam belt with this belt. I ordered the PAS with no AC belt as well as the alternator belt. I was going to delete the compressor for now and hold onto it to get it fixed eventually. Don't worry, I've decided to hold onto anything I remove for the vehicle to see if I can get it fixed up at some point. Am I correct by saying for the removal of the compressor, I just need to get some stoppers/covers for the tubes and connectors to the compressor so they don't get filled with dirt and water? I was going to keep the evaporator and condenser on for now. (I believe those were the names of the other parts for the AC system).

For the cam belt, I'm going to see if I can find any markings or receipts from the previous owner of when it was changed last since it's every 6 years or 60k. For the cam belt replacement, that's when I should get the water pump, tensioner, etc. since I'll already be in there?

I appreciate all the help and guidance so far, thank you very much!

[dapinky]

You seem to now have a plan which will get you mobile, with further work in the future - it's always good to have a plan!

Yes, the cam belt *should* be changed at 60k or 6y, and if there is no documentation available, I always do it as a 'commissioning' job. There are many schools of thought for the other components though.
20 years ago, when I got my first Elan, the parts were cheap and plentiful, so it made sense to just swap anything else which could be wearing out whilst I was in there - and general wisdom suggests that the waterpump is worthy of a swap anyway - certainly on an unknown vehicle.

However, since parts supply has dried up a bit I now look at it a bit differently.

On an unknown car, I will change belt, tensioner, idler, waterpump and both the PAS and Alternator belts (the last ones you are already doing).... but next time, I would only do the belt, then the belt/pump and just leave the tensioner/idler alone unless they were noisy.... Lotus (or Isuzu/GM) never specified a service interval for those parts anyway, as they are not considered to be scheduled change items, but most other manufacturers would have them swapped at anything between 80-150K as a matter of course.

The waterpump has probably been in the car for 30 years by now, so leaving one alone next time is unlikely to harm it - especially as you know that the coolant has been kept at the right concentration/level...... but again, it is one of those 'unknowns', and you can't really see if it is worn/corroded without removing it, and so you may as well fit a new one!

Some people will 'only' change the belt, and leave everything else undisturbed - and that isn't necessarily 'wrong' - but to me, the cost of a waterpump compared against time to get to it on another day, makes it worth changing...... obviously, if you are paying for labour, then you need to decide if paying an extra half-hour now, plus new coolant, is worth the risk against it failing in the next 6 years..... it probably won't, but who knows?

Having changed the tensioner/idler at the 30+ years stage, with whatever mileage is on the car, they should be good pretty well for the rest of its life, and do not really need worrying about unless they get noisy (unlikely!).

[TorqueHorse]

... I just need to get some stoppers/covers for the tubes and connectors to the compressor so they don't get filled with dirt and water?

Yes, some stoppers and then pull a vacuum on the system to make sure it is airtight (and the vacuum will help keep the stoppers in and help keep the corrosion down).
Also, when you get your system evacuated in order to pull the compressor, you might want to pull a vacuum before they/you disturb anything, just to get a baseline if it can hold a vacuum or not.