Porsche Enthusiasts Club Forum

Hi, got a problem where the coolant on my 84' 944 is backing out the expansion overflow once the car gets up to normal operating temp.

There's a also a kind of squeaking sound coming from around the front of the engine after we let her idle for a while.

Things we've checked/changed so far:

1. Checked oil filler and dipstick for milky oil = Oil looks fine and level was in the middle between min and max.
2. Pressure tested coolant system = No leaks found
3. Changed old thermostat (2 years old) for a brand new one from Porsche = Same problem with coolant backing out.
4. Removed the alternator belt and power steering belt = Squeaking still happens


Are there any other things I should check that will confirm or eliminate some possibilities?


Also does anyone know a good independent Porsche mechanic in the Kent area?

Thanks in advance.

I am fairly new to Porsche ownership so not quite in the anorak zone yet however the symptoms sound like a siezed water pump and if driven would end up a blown HG.
A good way to check HG failure of gas into water is feel the coolant hoses when car is running and if they go hard

Does the radiator heat up evenly? If we didn't already suspect the water pump, I would suspect an airlock.

1st off what is the water level like where is it sitting at cold in the tank? could it be overfilled, they don't like that and often find there own level in the tank.

on a basic level buy a new coolant tank cap

could be the water pump or air trapped personally I doubt it, but the squeaking does suggest the pump. I can't remember but can you lift the belt up off the pump pulley with the engine turned off, too see if you can spin the pump pulley. If its rough and grindy then its away, equally if it spins very freely or very stiff the impeller may have come off the other end. Mine was miles away from going and destroying the belts when I changed it!

are the hoses pressurising, ie do they feel hard or overly firm? Almost any garage can check for exhaust gases in the coolant system and I'm sure you could buy something on ebay to do this and that rules out the head gasket to a degree.