cwiert

I have the issue of constant heat in my car. I tested the flap above the foot well on the passenger side and it does go up when I start the car... so that vacuum is good.
Then I read the write-up by John Pirtle and the part about the heater control valve. I looked on my car and found another gift by the PO. It was installed backwards. So I disconnected it and put it on the right way...with the black side facing out towards the engine. Unfortunately, I can't test it now because I lost a lot of coolant in the process and have no more in my garage...I need to wait until this evening before I can go to the store and buy some more. So my question is, do you think that might have been my problem? What effect would a backwards installed heater control valve have?

docmirror

What did the flap inside the valve look like when you checked it? Was it all warped, deformed, missing the rubber o-ring, and basically thrashed? If so, it won't matter. If it looked ok, and your vacuum is good, and the line doesn't leak, and the control head works right, and the solenoid doesn't have an issue, then maybe, just maybe it'll stay closed.

Me, I just put a marble in the line up by the front so that NO hot coolant gets through until Oct.

cwiert

[hangs head in shame.] i didn't check it. i didn't know it could be checked. i just switched it around as fast as possible to minimize the geyser of coolant making its way onto my floor. maybe i'll take it out again and check before i refill my coolant level.

I've read about the marble trick before. Which side does the marble go on? the engine side or the firewall side?

docmirror

It doesn't matter, Just make sure it can't be sucked into the engine. There is a repl metal heater valve that is pretty cheap if you want to do it one time right. Contact Roger at 928sRUS. He has them in stock, will be to you in a day or so.

cwiert

i determined that the vacuum getting to the valve is working fine. but the valve itself is damaged. i removed the valve again and noticed a rubber seal inside it floating around. using my mouth, i was able to blow air through it both open and closed, so there's my answer. hopefully i just need a new valve and all will work fine. we'll see.

docmirror

Get a metal one.

Tom in Austin

%^*%$*$ heater valves, what a piece of %&*($$*$^

soontobered84

+1 on that, Doc

dr bob

You Texas guys must be way too tough on heater valves. Or I got the only good one.

123

I'm nowhere near Texas. Based on my experience, it could very well be that you got the only good plastic one. Things have been fine for me since I stopped trying plastic ones and put a metal one in.

Mrmerlin

and if you look carefully on the Porsche heater valve it says water entrant but in German,
the black side faces to the front of the engine

docmirror

Here's my last words on the subject.

The original heater control valve specified by Porsche for this application defined the materials carefully. Plastics can be made very resilient to temp and water/alky mix, but the composition and injection molding is rather expensive.

The originals lasted fairly well, maybe 12-15 years. The second batch that they OEMed from some place went out for bid, and the lowest bidder got the contract to make another lot of oh, say - 4000 units. But, since they were a profit making company, and the warrantee on the part was only going to be 1 year, they increased the VOCs a bit, or reduced the hardener a bit and the result was a POS valve that won't hold up.

We've been buying these ****ty valves for the past 2-9 years or whatever, and now we are seeing a 100% failure rate, after about a year, so the return to vendor rate is low. Actually, a very clever marketing method because each time it failed, we'd generally buy another one from the same bad lot.

I will use the metal valve, or use none at all before I would buy a plastic one again.

the flyin' scotsman

what Stan said............wassereintritt

what Doc said........I've a valve for the summer thats wired and glued............for the rest of the year its a new OEM valve that perhaps works.............Roger, got metal stock?

AO

I tried a metal one (audi) and it lasted 6mos. My Porsche one has lasted 2 years, but I think it leaks sometimes. Would like to find one that really works. Anyone have a for sure solution with a part number?

dr bob

Hmmm. Mines about 10 years old so it fit's Doc's model.