overheating

[dhorsfall2000]

Hi all, today i was driving my car and it started to overheat, the expansion tank filled up with water, when i stopped the car it went back down to just under normal, it is now doing it all the time, there are no visible leaks, im thinking water pump, any other ideas ??

[dhorsfall2000]

forgot to say, its a 2.0 azj engine, there is no oil in water or water in oil., seems like air is getting in the system somehow.

[itavaltalainen]

CO2 indicator test on coolant to exclude head gasket.

[baker1983]

Or the plastic water pump impeller failure

[dhorsfall2000]

thanks for the replies. also noticed that when i turn the heater on in the car when the engine temp is hot, the heater blows cold air out, dont know if this indicates anything else. car has done 155k miles.

[baker1983]

Sounds like water pump to me! Bought a mk4 1.8t where somebody thought the headgasket had gone because they changed the radiator, thermostat but still overheated! They never checked water pump so I got a bargain!

[dhorsfall2000]

Sounds like water pump to me! Bought a mk4 1.8t where somebody thought the headgasket had gone because they changed the radiator, thermostat but still overheated! They never checked water pump so I got a bargain!

hahaha nice one, will have a look at the pump then, cheers

[Wazzzer]

when it's up to temp see if there is any water flowing back into the header tank from the small top pipe, that will indicate if you have any flow...

Sounds very much like water pump to me though. Any record of it being done before?