Bill Lynch

I'm in the process of finishing up the R12 to R134 conversion. In the process of replacing all (and I do mean all) the o-rings I have come across 2 locations for which I am having difficulty finding specific size info.

Location 1 on the outlet of the TXV. the porsche part number is 944.573.215.00. This is said to be a rubber o-ring. Not sure why when all of the others are HBNR. I'm afraid to just buy the part put it in and then have the o-ring fail due to pressure and oil exposure over time. If someone can tell me the size I will find my own replacement.

Location 2 is the manifold which sits on top of the (denso) compressor (leads to the suction and discharge ports). These 4 o-rings are not listed in the PET. Upon disassembly I found 3 of the 4 (black originals) to be broken. this explains why the PO kept leaking refrigerant. The size (ID) is approximately 17.5-18 mm and the grove depth is 1.5mm. I've placed a 17.8 x 2.5 mm o-ring in the groove. the ID is a good fit, but the OD appears small. similarly the cross section is proud of the groove face by only a slight amount. So I figure I need a 17.8 x 3mm o-ring but I am not finding them anywhere. Can anyone tell me the right size and a source for buying them?

Thanks

harveyf

Bill: Can't help you specifically but I just did o-rings on my 928 and bought them all from Roger at 928RUS. This included the 4 under the cap on top of the compressor.

Griffiths in NJ also might be able to help you. And of course there is Paragon and Pelican.

Tom M'Guinn

Been a long time, but I changed mine (and the accessible hose) with PNCA parts using part numbers from PET. What year is your car/a/c system?

Spidey944

having called the local Pcar dealer many times, I am sure they can find this info quickly. Even if you dont have a local one, just call one and they will look it up for you, just ask them for the part numbers.

griffiths

Most of the orings are standard 6,8,10. Drop me a pm and I'll tell ya what the manifold size is. By the way, all Griffiths R134a conversion kits come with complete o-ring sets.

WWW.Griffiths. com

NoRush993/951

Pelican has an a/c o-ring kit that has every ring size in the box. I picked it up for my 951 since it was easier than running down every ring size and quantity needed.

Bill Lynch

Well I cobbled the system together well enough for it to hold pressure for a couple of days. So tonight I fired it up to check engagement of the clutch (it works) and the High temp high fan speed (it works too) then filled the system. A bit of bad news; the pressures are all wrong and point at equalization across the compressor (low side to high, high side to low). Hmmm. I've PM'd Grif for some advise. So for now I'll drive with the windows down (in Houston Texas) until it gets too miserable.

BTW - awhile back I had the dreaded no start. Was getting tach bounce and fuel but no spark. I replaced the coil with one from another Rennlister and she came back to life. Would like to say though, for those out there having this problem, clean the connectors on the ref sensor\speed sensor and this may cure your problem. I did this as part of the hunt for the fix and think this may have been part of the problem and part of the solution, kinda wished I'd tested things one step at a time so I knew for sure. Oh well.

Time to go put my tools away (for today)

Bill

william_b_noble

I've converted about 5 cars to 134 by just adding the proper oil and refilling - never had an o-ring problem - I used a pressure manifold to determine when it's full - you can't use the sight glass like you would with R-12 -

cas951

Would you have a diagram of where the seals go? I also found to have only 3 of 4 seals.

V2Rocket

for the early 944 AC system, the o-rings on the TXV can be found in the "ac oring assortment" sold at your local auto store.
i dont remember the exact sizes but i can post them later.

Tiger03447

If you can find the right sized ones, use the green ones..they're made for 134a..hold pressure better than the others...