Porsche Enthusiasts Club Forum

Hi all,

Hoping to change my a/c compressor next week and wanted to seek a few opinions regarding 1/ which compressor to use 2/ the job itself 3/regassing

I've got a bad pulley bearing, so after the headache taking off the pulley with the lines still attached trying to gave regassing- I found it was leaking around the seals behind the pulley.

1/ which compressor shall i change to? I'm either going to recon mine or consider a kuehl compressor which the american forums seems to recommend as its the same price as a recon unit

2/ Is the job as simple as swapping over? I already have my car converted to 134a - should I be ok using the same hoses etc.

3/ Whats the cheapest way to regas it?

To recharge it properly you need professional equipment, as the system should be pulled into a deep vacuum for at least 30 minutes in order to boil off all the moisture in the system before charging with refrigerant. You should be able to get a mobile guy to do it for around 60 quid.

I was going to buy the Kuehl compressor but in the end I stayed with the original Denso unit brought New from the USA for £280 brought it back whilst on a trip

I've changed over my compressor as the nose seal was leaking on mine. I have no idea about the other compressor you mentioned, I was fortunate enough to benefit from Ken collecting a new one and his other not new but perfectly functional unit now resides in my car. As does his almost new but not quite condenser as well come to think of it!

Once you have it back together get a new dryer and then get the system vacc'ed out as mentioned and then fill her up again. 30 oz from empty IIRC.

I have a contact in Glasgow who did my vac and re-gas for buttons which was nice.

Stuart

Is the compressor job a simple swap out job? Do I need to fill with oil beforehand?

Pretty easy. The only difficulty may be seized connectors. Get new seals for the disturbed pipe ends and there is also 4 seals under the adapter plate. So 6 seals in total. You won't need to put oil in the compressor although a wee dab of ester oil into the system after the vac but before the refill should see you right. No more than 10mm of ester oil.

Stuart

Thanks, I see the 2 seals on the a/c hoses onto the compressor - and then 2 on the drier. What are the other ones you're referring to?

There is an adapter plate on the compressor. It will become apparent when you remove it, it is what attaches the pipework to the compressor. A new compressor would likely not have this. There are 4 seals between it and the compressor.

Stuart

Correct procedure is to empty the oil from the old compressor, measure it. Drain any oil from the new compressor. and add the same amount of fresh oil to the system that you retrieved from the old one.. You should really replace the drier if the system's been open to atmosphere as well, but that's your call.

Thanks! I will empty out the oil as mentioned, I'll need to check whether my system is PAG or ester oil as well I think I have a sticker somewhere. Bit of a nightmare, I thought it would be a simple bearing change on the pulley, and I've ended up replacing the compressor.
I could have just put the new bearing on but I want this job done perfect.
I also have a new drier and o-rings on their way, thanks for that tip as well, definitely not going to skimp on a fairly inexpensive part like that.

Where would you recommend looking for a seal kit? There a lot out there, but I'm looking to do the job properly so don't want to get inferior o-rings. (My car is converted to R134a already)

I got the o-rings from OPC. Not cheap. The pipe ends were about a quid each but the ones under the adapter plate were around 4 quid each IIRC. I run R -134a also but did not do a conversion. Seals are seals at the end of the day and the addition of some ester oil after the vac and before the fill of gas keeps everything happy. It's been running fine for over a year and hasn't lost any gas. I listened to many stories of conversions but a few learned a/c people kept me right.

Stuart

We fitted a new A/C compressor and drier last year when putting the car back on the road after a 4 year lay up....my son had a boxed set of suitable A/C seals in his workshop, we just chose the correct size (green in colour) and replaced new for old. Regassed, my son has the equipment so no cost to me and all has been well ever since, used A/C for the first time this year last week, nice to have it working again, the old pump seized more than 10 years ago.....

Pete