RHollingUK

Hi all, need to replace the evaporator on my 96 993 C2 Tip. Loses all gas in a 24 hour period. Replaced the condenser, receiver dryer, lines from engine area to condenser so now booked in to change the evaporator. Looking at previous posts on this topic the Griffiths unit is by far the best solution - unfortunately they tell me that they are retooling so out of stock for the foreseeable future... That leaves me with several options and I would appreciate suggestions as to the best solution. There's the Porsche original unit at more than 4 times the price of the alternative pattern parts which seems madness as I think they are made by a third party supplier anyway. I can get evaporators by Mahle, Behr, NRF, Hella Black Magic, and a number of others. Does anyone have any experience of any of these brands, which should I choose?
Any advice appreciated. Thanks in advance

Richard

1996 993 C2 Tip, 2004 996 Turbo Tip.
1989 928 S4 gone
1984 3.2 Carrera gone

abiazis

Make sure you replace the expansion valve also while you are at it......about a $250 part in my recollection........I rebuilt the entire system for $1350 total in parts at the time - evaporator, dryer, bunch of o-rings, condenser, etc....I have heard that the Mahle evaporator is good quality and durable.......

pp000830

Hi Richard,
You seem to have replaced lots of stuff in different areas of the system. Did you have dye added to the system and use a UV light to verify the point of the leak?
Before you go to the trouble of the very invasive procedure I would verify the point of leaking.
Sometimes a sudden large leak can simply be a failed Schrader valve at the charging /evacuation ports.
I would think an evaporator leak would initially be slow and develop over time.
Andy

LimeyBoy

Just completed this and I wanted the Griffiths but believed they were out of stock. So I bought the all aluminum FVD evaporator, and then saw on this board there were Griffiths in stock somewhere - so you may want to search.
The FVD seems decent quality - and leak tight, which is nice. It was a lot tighter reattaching the two gas hoses (onto the expansion valve block) when near the end of the reinstall - seems the FVD ports are a few mm lower than on the OEM evap I removed.
Absolutely replace the expansion valve.
You can buy all the suitcase foam seals and rubber stripping which I did (search PET), and then found all my originals were still in decent condition. So maybe determine that need after the suitcase has been removed and split.....
There are 3 foam pieces that require sticking to the new evap - two strips down the 'front' to seal the evap in the opening (I re-used because good shape), and one wrapped around the gas ports to block air going thro that top suitcase opening point - I didnt see this part on the PET and my foam was shot. Made a new piece from some new foam I had.
When I initially installed the new evap, I did so without the suitcase being fitted but with a complete AC circuit. This allowed me to leak test the new parts more easily. When I was happy, I disconnected the evap and built it into the suitcase.
Be careful of the dryer, you want to install this as late as possible and keep it blocked off or under a vacuum to prevent moisture ingress.
Good luck.

RHollingUK

Thanks Andy,
Yes, have been adding dye. We replaced the lines because the dye highlighted a leak and unable to resolve without replacing as they were rounding off. There seemed to be a small leak on the condenser as well so replaced that. I'll look again at the schrader valves, completely agree that the evaporator is a big job and keen not to waste the cash if not required, however seems likely that the evaporator is the culprit but agree that losing 850g of gas in 24 hours is a big leak
Richard

bobbyp

Since this seems to be the simplest first step, does anybody know the specs on the Schrader valves for the hi and low pressure charging ports?

TDW993

It sounds like a big leak. I would think that you would see the dye in or around the evaporator drain if that is the case.

pp000830

Hi Richard,
If the evaporator is leaking the dye will be seen in the condensate dripping under the car.
Andy ;-)