notthd

So- I started out with a ride to the neighbors- car ran temp up higher than usual, started into the red, popped the hood and the fans were not running but did when you pushed the AC button. Shut her down and it was odd that the radiator did not seem hot nor did the hoses have much pressure for a car overheating ...

No worries- I have a spare radiator out of the other car- swapped the fan sensor and while I was in there changed out the thermostat.- that snap ring is a bitch with everything still in the car....

Filled every hose as I installed pieces including the radiator inlet and outlet, topped her off, ran the car, opened the bleed screw and repeated a few times. Thought I still had air in her so I parked on a steep hill, squezzed hoses, and made a fitting so I could attach a long hose with coolant in it to fill and bleed at the same time. Eventually on more bubbles out the bleed screw.

Now she still overheats, Fans still do not come on, and there is no heat
Could the heater contol valve be trapping air in the system? What is considered the "hot" position in our cars? I am actually going to read the Radiator internal temp with a remote gauge to see if the fans are not on because the temp is not high enough.

Something else odd is with the AC pressed and the fans on the car still did not cool down.. Any help or comments are welcomed- Cheers, Mike

PorscheDude1

Try swapping the fan relay for a known good relay.

Lemming

My immediate thought was to just try tapping on the temp gauge cover, see if it drops the temp as it sounds like an electrical/grounding problems that many (including myself) have had. However, that does not explain the lack of cabin heat?

When you turn the cabin heat on, does the HCV lift?

PorscheG96

This is what I'm thinking too. Now there's obviously something else the matter because the heat isn't coming on, but maybe the engine wasn't running hot before and the gauge just wasn't grounding well.

Damian in NJ

Tim, here's a rule from my old days as a research scientist-never tap the cover of an instrument harder the you would use a knuckle on the bridge of your nose!

PorscheDude1

Also try jacking up the front of the car when bleeding the system, this will help get the air pockets to the high point of the system.

Lemming

Hmm, I'm a research scientist, but I firmly believe it brute force when necessary

968workaholic

Water Pump isn't spinning? Thank you Porsche for plastic impellers! Of course if the tap on the instrument cluster trick doesn't work....

jpk

I recently swapped out my thermostat for a new one; when I initially filled the system and bled it, the front was still up on stands. I was not getting any heat into the cabin untill I lowered the front back down to the ground. I blead it onece more with the car level and it's been fine since.

Did you test the thermostat that you installed? I removed a Whaller rated at 83 c and installed a Stant premium rated for the same 83 c. There's an almost 20 degree difference in how those two operate; the Stant starts to open at the rated 180 deg. F, the Whaller is pretty much fully open by then. With the Whaller, I didn't have much cabin heat and on a real cold day, the temp guage never got above the bottom marks. With the Stant, I have plenty of heat and the temp guage sits right at the middle.

The lesson here is that not all thermostats are created equal; I'm not claiming either one was bad, just that there is a big difference between the operation of two equally rated thermostats.

Todd951968

+1 for the plastic impellers in the water pump.

notthd

Thanks for all the ideas, here's some more info- I feel the gauge is correct as far as the first time the car overheated since it was steaming out the overflow- so it is hot. Also the fluid out the bleed hole is extremely hot as it gets close to redline. I did bleed the car on a pretty steep hill- nose up...

Fan relay would mean the fans never come on....correct?- they do operate when you push the AC button but even with them on the fans do not keep the engine from overheating or even bring the temp down.... I think she's just not moving the coolant.

I am going to see what the temp inside the radiator and motor are tommorrow. I feel my greatest fears are coming true... water pump impeller....

Thanks guys, Mike