Ell

I have an 86 928S that I have been working on replacing the timing belt on. The new belt is in place, tensioner rebuilt, intake manifold couplers replaced, new hoses, belts, plugs, rotors, and caps, new thermostat, and inner seal. I had everything back together, started the car and filled the radiator. That is when we found the thermostat housing leaking. The O-ring didn’t look like the original however it did fit inside the housing slightly touching the thermostat. Wanting to get this completed today since it is in my neighbor’s garage, I checked with Napa and they had the O-ring. Again this didn’t look like the second O-ring and the original was already trashed, however this one fit on the outer lip of the thermostat. Re-installed everything and again the leak.

Any suggestions on what the right O-ring looks like, how it fits, and most importantly how to stop the leak?

Ell

Jay Wellwood

The 'other' vendors (ie NAPA, et all) carry the wrong size oring for the Tstat housing. The correct oring is about 4 times thicker than what they supply.

Any of the Big 3 can get you the correct oring, but you'll have to wait for it to arrive.

One option might be to inspect and reuse the original, if it's still available.

hth-

Ell

Jay,
The O-ring that I got from one of the big three had a larger diameter, however it was not thicker. I believe that the O-ring that I got from Napa was thicker but smaller in diameter.
I will try and call the 928 vendor tomorrow and check with them.

Thank you.

Ell