no heat!

[alpo318]

I recently had my 1987 porsche 944's top end rebuilt and now I have no heat. I can let car run for 30 min. and it will not heat up or overheat! Heat did work just recently after rebuid however I have no heat now. Also the engine temp stays very low. Is it the thermostat or maybe the heater valve. Honestly don't think it is the heater core! I am new here so thanks for any help.

[Jrboulder]

Bubbles in the coolant. They're evil.

[175mph951]

check the vacuum line to the heater valve

[Ga 951]

sounds to me like you need to bleed the coolant system. If you have air in the h. core..no heat.

start car and set heat to full hot, run until radiator fans run and cut off ( thermostat open ), then open the bleed valve and leave open until you get a good STEADY stream of coolant for 15sec or so. Close bleeder.

If the vac line is off the heat control valve, you should have continuous heat!

[mr5296]

where is the bleed valve located

[ernie9944]

Originally Posted by mr5296

where is the bleed valve located

On late car on top of water socket (elbow upper rad hose) early car top of rad hose (red plug)__86
___83

[HondaDustR]

Does the radiator get warm if you sit and run for awhile? There is heat produced and it's got to go somewhere. If there's enough of a void in the system, the fans will never come on because the temp sensor is fairly high up in the radiator. Make sure the system is filled to the point of coolant coming out of the bleeder screw before running up to temp. It is entirely possible that the thermostat could be stuck open or even missing, since it has happened so abruptly after some major work. I had run with no thermostat once while running a radiator flush some time ago. The car took forever to get hot and would basicly never heat up while driving.

[grendiers]

Define heat? Snort, 924 and barely heat from factory~!