This is how I installed the new thermostat, the old one came out same way.


I also found this thread on pelican for the same year and model of my car:

http://forums.pelicanparts.com/porsche-928-technical-forum/740172-1980-porsche-928-overheating.html

Same exact symptoms besides the brake issues! Looks like at the end of the thread the op resolved the gauge by replacing the temp sensor. Where exactly is that?

I don't think my electric fan even comes on, I'll try to jumper it soon for functionality, where would you jumper it to?

 

Good resource for what is what under the hood:

http://members.rennlist.com/v1uhoh/underthe.htm

 

Awesome thanks Itoolio!

 

You can test the electric fan by jumpering fan relay terminals 30 and 87 in the CEB (XVIII, I think, but double check!)

 

OK so basically the same method as jumping the fuel pump relay. Gotcha. I'll try that. I'm wondering if my cooling system is fine and gauge is just whacky. I'll need to determine that before ripping through the water pump and such. Thanks.

 

You need a new timing belt and water pump, anyway. If you don't know that this maintenance was recently done, then you'll be best served to do it now. They DO fail.

I've got my nickel on it that yours already has.

 

How can you tell the timing belt is kaput? It runs, and other than a vacuum leak causing a rough idle, it runs well without missing. When I hold the broke vacuum line together, it idles around 700, sounds good, and has good throttle response.

 

Replacing the belt is just good practice. When you do one, you should do the other. The water pump is driven by the timing belt. No telling how old your belt is. I would recommend replacing it.

 

Agreed, but down the road, unless it actually does prevent me from getting car cooling, which it may be doing and my gauge hates me. I want to sort that out first taking on something so expensive and involved. It's not time to punt yet! I think I can eek out another first and ten.

 

Did I just get flagged for a false start?

 

It seems odd, though, that a sensor and sender would malfunction at the exact time that you were doing other cooling system work. Did you drain and refill on the same day, or did things have time to dry up (out) in between?

 

to be sure at what your finding you need an IR gun,
to test the hose temps the top rad hose should run at 185/190F.
the bottom should be at 170F.
NOTE if the gauge is giving erratic readings then the connectors should be cut off and replaced with fresh parts and the sender replaced as well.

NOTE if the temp gauge goes into the red zone after running for 5 mins or less and the radiator hoses are both cool then your waterpump impeller is failed or the thermostat is stuck closed

 

Hmm, well, it only cost me a nickel

 

..

 

Holy four-year-old thread revival, Batman!