jetta overheating

[jettajz]

I have a 2000 Jetta that is overheating..... the thermostat is tested and is working. i think it is the water pump that has gone bad but i want to be sure befor i go through all the trouble of getting to it. Anyone know how to test the water pump or any sure signs that is my problem?

Thanks so much for the helpful insight.

jettajz

[airic]

Is there a leak, or is the system holding pressure? Is there a belt on the water pump?
Does it have coolant?
Is the engine actually getting hot, or is the gauge just saying it is hot?

[CaseyVR6]

If you want to see that it's the pump for sure, eliminate everything else that's cheaper first. Could be the temp. sensor is bad, that the radiator needs to be flushed, that the gauge in the dash is bad...

You haven't added green antifreeze to the system, have you? If so, they mix together like lemon juice and milk (sludge results) that causes the system to run inefficiently. If you did add green, you've got a few hours of system flushing to do.

[Wolfie01]

You can tell when you turn on the car and if one of the hose's is cold and the other is hot then its deff the water pump. I had the same situation and its deff the water pump.

[ricebike]

wolf, that's incorrect...

if u just turn on the vehicle, the t stat is still closed, giving u the temp difference between the hoses.

now, after the gauge picks up/ ~10 min @ idle, if they still feel as described by u, it would most likely be a stuck t stat...

the free loaner tool from autozone / another parts slinger, would give u a pressure tester to do it while your car is cold. pump it up to the specified pressure from the factory <don't go over this psi or u may blow out the heater core!>

then, u can look 4 leaks, starting around the hose clamps, that weep hole of the water pump, hoses around the intake manifold & firewall, etc.

u can also test the cap/ just replace it altogether. 1 psi= ~3 degrees F & u need that pressure/temp differential between the air<>radiator for a good heat exchange.


OP, did u remove the t stat to test it? then put it back in? if so, u have to be sure to bleed the air outta the system. some cars are harder to do than others.

[jettajz]

I have replaced the thermostat and eliminated everything easy. Now I am going to replace the water pump. While I am there I am going to replace the timing belt, timing belt tensioner, and drive belt because I have 70K on my car and this has never been done.