Owners Forums for Ford and Volkswagen MPVs / SUVs

Hi - in the article Ford Galaxy - Heater blowing cold air and engine overheating under load - it states that "Firstly run the engine with the cap removed, now observe the coolant in the bottle you should be able to see coolant returning to the bottle via the return hose, if you cannot see this happening then remove the return pipe and check the restrictor inside the pipe is not blocked."
My question is how much coolant should be returning to the expansion tank and should it be a steady flow - I have observed an intermittent trickle when engine running and temperature gauge is about 90degrees. The trickle will last maybe 10seconds and then stop for 20 seconds. Is this normal? thanks

Hello and 
should be pretty much constant, when you see nothing it's probably ejecting air but you really should check the water pump impeller first has not become detached from the shaft.
You can do this by removing the thermostat housing and try to rotate impeller, it's possible that it's slipping on the pump shaft.

Hi,
I had same symptoms, would tickover in idle without over heating but blowing cold air from vents. As soon as started driving within a couple of miles it over heated. I was towing a caravan at the time. Turned out to be waterpump. The plastic impeller had come loose and was spinning on the metal shaft, apparently a common problem on pumps with plastic impellers. I know you've had problems with head gaskets before but wheras they cost money to diagnose properly, the waterpump impeller costs nothing and hence is worth checking first. After removing the thermostat put your finger in the hole and you can feel the impeller. If the blades on the impeller are broken or you can turn the impeller with your finger the waterpump needs replacing. When ordering make sure it has a metal impeller which will ensure you don't have this problem again. I didn't check on mine but if the pumps not pumping properly it should affect the amount of coolant returning to the reservoir.
If its not the pump then perhaps investigate head gasket.