xcracer

My 87 944 base na has started to run on the hot side. Temp gauge starts at bottom and climbs as it always has but now goes beyond 3/4 on the temp gauge. the fans kick on but cannot keep the temp down like in the past. I thought that it was the thermostat. I flushed the system, found that my circlip was broke into 3 pieces but everything was still in place. I put a new matching 180 degree Thermo in and bled the system and still the same problem. The car will sit there and idle and temp will slowly climb, fans kick on temp keeps climbing and I shut her down before she gets too hot. The water pump pulley is not slipping on its shaft, I marked it and ran it. no leak from a weep hole and no noise. I squeezed the top hose when she was at operation temp and let go and could not feel any flow but how accurate is that? The hose was so hot I had a thick glove. Is there any was this thing is turning but not pumping? Is there a way to check without pulling the pump? With the infrared thermometer the upper hose was about 160 near the motor and 110 near the radiator. The top of the radiator never read higher than 90. Advice? gnccquadracer@hotmail.com

PerceptionProblem

Have you tried replacing your temp sensor? I have a similar problem, and although that didn't cure my problem, it helped greatly. Also make sure you've properly bled the air out of the system. clarks-garage has a good write-up.

Something I've been keeping in mind is that the stock temp instrument is measuring in C while we are looking at F. (water boils at over 200F but only at 100C)

944_S_TYPE

Do you have any other electrical problems? It may just be an indication problem, Caused by poor ground wires. Also, As Perception problem noted. Triple check the bleeding proceedure. Do you get hot air at the vents inside the car?? If so the pump is spinning.

dhoffner

I would also check and see if your radiator is plugged up. If you've got no airflow through the radiator, it won't cool. If it is plugged up, take it to a self serve carwash and use the high pressure nozzle to clean it out.

kingston944

Can you turn the water pump pulley ?? Prehaps the timing belt is to loose as was my case when I bought my car temp was at the redline and you could turn the pulley easy by hand.

PerceptionProblem

[QUOTE=944_S_TYPE;8854843 Do you get hot air at the vents inside the car?? If so the pump is spinning.[/QUOTE]

My car, when warmed up, has ambient temps that are a bit warmer than comfortable. . . I've fixed the infamous heater clip, and while that helped greatly, I'm still getting rather warm on the temp gauge and in the cab. Could you explain what you mean a little better for me? Thank you.

pnbell

Sounds like you are talking about HVAC temp vs Engine Running Temp...

If you are talking about getting Hot Air thru the vents (even with **** set to Cold) it is probably your Heater Control Valve. This valve uses engine vacuum to close and stop Hot coolant from flowing into the Heater Core.. Over time the Vacuum Diaphragm does seal, and can not pull enough vacuum to close the Heater Valve..

Looks like this :http://944time.com/porsche/images/20...trol-valve.jpg
Pretty Easy/cheap to Replace; Actually the Black Piece Just Twists off, and the New one can be installed with out disconnecting the coolant hose.

*944_S_TYPE was simply saying that if your Heat works inside the car, the Water Pump must be pushing coolant around..

It sounds like either your car is running at a fine Temp (Gauge Issue); or you still haven't gotten all the Air out, and the pocket of air is sitting at the top of your head where the thermometer is located -and getting HOT!

** Get the car hot; Shut it off; open the Bleeder screw a little bit and listen for air bleeding out, followed by coolant. Sometimes with our cars you have to bleed the system a few times.

PerceptionProblem

I've already replaced my heater control valve, and used a combo of bleeding the air out by warming up the car then using the bleeder screw and using a radiator pressure tester from (local parts house) and opening the bleeder.


While I had my cluster out a few days ago, I moved the rod held in place by the heater clip so the flap is more closed than it was before. Now the hvac heat is no longer unbearable (let's hear me say that on the next 95F day, lol) but my engine temp is still acting funny.

And I think that it might be either a faulty fan temp switch or a faulty fan relay. The reason I say that is both of my fans do work, but only on the high setting. So I'm gonna get a new temp switch and pray that I don't have to spend an insane amount of coin on a new fan relay.

thx for your help once again, friend. ^___^

schip43

Radiator cap? I blew a head-gasket on my NA over that one! The rubber ring was'nt sealing on the coolant tank!

xcracer

Update to my original post: I gained access to the radiator and found some little rocks and a few leaves at the bottom. I got a tiny screw driver and picked it clean, flushed it out. I put a new Rad cap-stock pressure, Complete cooling system flush, bled system many times. Heater works great. Seemed to lower the temp reading a bit and the high speed fans ran less. Temp just below 3/4. Now shes back to 3/4 and a bit higher again. High speed fans are running. You would think that it would run a little cooler at 70-75 mph but no. Does the plastic "skid plate" or whatever you call it that is underneath have anything to do with it?

kingston944

My 87 n/a has skid plate and never an issue after I did all belts rollers and water pump ect . I did clean all the crap out of fins in rad by gently dropping it "jolting" it on the garage floor, lots of stuff came out and used compressed air to help clean fins blowing air from engine side to the front , then did rad flush in basment sink. All is great runs at proper temp now . Yea I know dropping it on garage floor !!

pnbell

i've heard the 'skid plate' actually helps in cooling by creating a negative pressure zone behind the radiator while driving...

Does your Temp Gauge read cooler when all the lights are off by any chance? Mine always reads hotter with the lights on, due to some ground issue...