New Water Pump Now Overheating

[jolene]

Just had cambelt and water pump changed as we bought a car with no service history and it's done just over 100k. Since it's been done the car is blowing cold air out of the heaters and keeps overheating. Phoned the garage who told me to keep an eye on it as it could be the head gasket. When I checked the water level the first time it was way below minimum so I topped it up. The next time I checked it it was way over maximum - HELP!

There was no problem with the car overheating or blowing cold air before it went into the garage so why would it now need a head gasket? Could it be something simple - I'm now not convinced the gargae I went to is very knowledgable and as I have just spent all my savings getting this done I'm really worried that they've messed my car up.

 

[MIkey kc]

sounds like it has air in the coolant system, you should get the car running and let it warm completely up with the header tank cap off to let the air lock out. that for sure will fix your problem. if it starts to over heat with the cap off just turn the engine off and let it cool down abit and then start again. hope this helps
mike

 

[Disco_Biscuit]

What engine is in it? petrol or tdi, the 150/160 tdi's run a slightly different depth water pump to the regular diesels, could be the wrong pump

 

[jolene]

it is Tdi but it's 110, did try letting it warm up yesterday pm without the cap on. went up to almost 90 but then I turned it off - should I let it get hotter than that?

 

[MIkey kc]

yeah take it up to 90 the fans should kick in around there, if they dont you have air in the system. if it starts getting to 100 turn it off and let it cool down for abit.

 

[Disco_Biscuit]

Thats the non PD lump so all pumps should be the same, could be air in the system, the way we usually bleed them at work is run them at a high rpm ie 3k with the cap off heater on hot, keep checking the level and checking the heater dont put the cap on till its just starting to boil over( it might not boil over fans might cut in). then slip the cap on and run at 3k till cooling fans cut in, usually 95-100 ish.

worth a try.

 

[jolene]

thanks for that I was afraid to run it for too long with the cap off - wish it wasn't dark now!

 

[jolene]

Thanks Guys - my car is warm inside at last! Fingers crossed this has fixed it.

 

[MIkey kc]

good stuff

 

[jolene]

*!!* it's doing it again! Any suggestions as to what we should try next??
Should we change the thermostat?

The garage is still saying that it's probably the head gasket even though they've tested the water in the header tank and it's not showing any signs of a head gasket leak and there's no water in the oil.

As ever I would be extremely grateful if anyone has any suggestion?

 

[MIkey kc]

bugger, yeah id say next step is a thermostat then

 

[acidstrato]

is your coolant actually boiling up?

 

[jolene]

When it overheats it does boil up. Earlier though the vents started to blow cold but the engine temperature did not move over 90 although I didn't drive it very far after the vents went cold. When I stopped the car the engine fans were on.

 

[L9 GOW]

does sound like the water pump!
if it was the thermostat then the fans wouldnt cut in?
run it up to temp and make sure both the pipes coming from the radiator are hot so you know the water is circulating!
when it is up to temp also chek if the heater is hot if its not then keep the revs up to about 3k and see if the heater gets hot if it does then i would probably put it down to a faulty water pump!
hope this helps!