944 AC compressor service

[os951]

Did some minor service to a 951 AC compressor. I will include pictures here, after all a picture tells more than a thousand words. I don't even know english words for all the parts inside compressor []

Starting point

A bit cleaned

Starting to remove magnetic clutch/switch

Removed

Take two washers off

And woodruff key

like felt washer as well

Remove circlip from the saft

Removing the front cover

Cover off, next remove black odd looking "washer"

Remove smaller odd looking "washer" as well

Remove main safts washer/seals (these are what usually starts to leak)

Take hose attachment plate off

Remove rear cover and "washers"

Separate compressor body halves from each other

Pistons can be seen now easily

Take pistons off from the eccentric saft

Take saft bearings off. You can also remove front & rear end plates

In pieces. Wash all parts now properly

After a cleanup procedure you can start to assemble parts back together again

Put pistons back to eccentric saft

And assemble front part of the compressor

New seals & washers for front cover and the main saft

Install front cover bolts, turn by hand as long as they go

And tension to right torque

Install main saft seals

And the circlip

Take a cup of coffee

Do not install hose attachment plate like i did. It's wrong way (upside down)

Install the "magnetic switch" with circlip

Put belt wheel on (with ciclip)

Put woodruf key back to the main saft

Install the front plate (remember two small washers first) & felt/brass washer

Push front plate gently on

Tighten the washer & nut to the main saft

You are ready, take a beer

One ready, two to go

 

[944 man]

Epic.

 

[PSH]

top stuff Olli... i love it...

Pete

 

[Diver944]

Thanks Oli.

The inside of those pumps contain some of the most weirdass components I've ever seen []

 

[Mike_Pollock]

Superb !!!


Paul, one for the vaults

 

[bmnelsc]

Great stuff Oli - thank you. I've been looking at some other material and they were short on pictures and long on talk. Yours is great - plenty of pictures to follow along.

I'm going to try this myself as it took 3 years for my AC to leak out so I'm pretty sure new seals will fix it. With your tutorial, I have hope []

 

[PSH]

My Compressor packed up some 8 years ago and I've never looked at it, this is giving me the incentive to see what's up although I think it may need more than just seals. Is there a list on-line of spare parts available for this job?

Pete

 

[os951]

Thanks guys. I looked proper instructions with pictures how to do, but coudn't find any. So i decided to take pictures while i was doing this. After all, nothing special in this job, you just need to be sure how to put pieces back. I also installed pistons bach to the same cylinders i took them out. Do this for a fellow 951 owner. Now when i have rehearsed this, i can do mys son's project cars compressor a bit better. Have a 968 AC system ready to be installed, but compressor might need some tlc. Actually compressor is the one which can be seen from a pictures where are three compressors. 968 one is already for R134, but it looks more or less similar than 951 & S2 compressors i have. The only difference is the lack of low pressure "vent" which is located on hose attachment plate on 944 models. I suppose it was not needed since there are two high pressure "vents" attached to the hoses after all. I can supply all necessary parts to accomplish compressor overhaul.

 

[944Scott]

MIne appears to be leaking around the joint of the main two parts of the body as you can see the dye they put in last time.

 

[ukmastiff]

I cant believe no one spotted your mistake ?

It should have been a cup of tea []

On a serious note what a fantastic breakdown , how much is the seal kit to do this job

Regards Mas

 

[Hilux]

Great write up - must be made a sticky.

If the car is in bits change all the seals throughout and you can then use the current types of gas (R134a???) as R12 as used when new is banned and (in theory) unavailable but was/is still the best. The molecular size of the current gas allows it to leak past old and worn seals and uses different oils (and might not use shraeder valves) so it needs complete purging and vacuuming - but you dont need as much of the new stuff.

 

[os951]

The seals i used are both R12 & R134 compatible. 968 used R134 from a start and compressor is identical to 951 one. It is good to change the dryer as well when you change from R12 to something else. Denso used mineral based Denso 6 oils with R12 and Denso 8 ester oil with R134. I should calculate what seal kit would cost shipped to UK. Can do that when i return from our summer cottage (writing this with my mobile phone)

It should have been a cup of tea

My bad, you're absolutely right. I just drink coffee during the daytime and tea late at night []

 

[Hilux]

The seals i used are both R12 & R134 compatible. 968 used R134 from a start and compressor is identical to 951 one. It is good to change the dryer as well when you change from R12 to something else. Denso used mineral based Denso 6 oils with R12 and Denso 8 ester oil with R134. I should calculate what seal kit would cost shipped to UK. Can do that when i return from our summer cottage (writing this with my mobile phone)

I only comment/mention it in that if anyone carries out such a refurb and then fills the system they need to be aware that you need to ensure the whole system is R134a compatible or a lot of money spent may end in disappointment.

If it is properly purged and vacuumed by someone who knows what they are doing the different oils issue disappears but if not then they are not compatible. Disposable R134a canisters are now banned I believe but there may be some lying around however the two gasses and oils are not compatible.

 

[Super_Marv]

Beautiful work as always Ollie!

By the way, it's shaft, not saft...not complaining in anyway, your English is far better than my Finnish!

 

[os951]

OK, thanks for correcting me. Saft is Swedish and means Juice. Too much hassle when you know poorly several languages, you keep mixing up words [] But if i use for example Google translator and write in Finnish, the result would be something else than a fluent English []

 

[Super_Marv]

What did you wash the parts with, by the way? They came up wonderfully clean.

 

[os951]

I used Acetone & Xylene

 

[TTM]

"Saft" is also German/Danish for "Juice"... [8|]

 

[os951]

That's correct, hear it every day, since my kids talk swiss-german with their mother . Another difficult word is break, which I mismatch to brake. I suppose break have a different meaning in few languages, at least French station wagons are usually called breaks. When you write a foreign lanuage in the net, you do not pay too much attention to spelling []