VR6 Fan Switch Questions

[syncro]

What happens when you turn the air con on?

[bsting]

A mate here who has a vr6 had a similar problem to how you are describing.
Found out the waterpump impeller had broken off

He fitted a new waterpump its all good now.

[WA Euro]

here's a way you can check if your water pump is working.

Start your car cold with header tank cap off. Coolant should be pumping out of the return hose (top one) if the pump us pumping. You may have to increase the revs slightly to notice it though.

As for the fan coming on after switch off - from my understanding of VR's, when you switch your engine off, the elec pump keeps the coolant circulating and the fan runs to cool the circulating coolant. Genius.

If your gauge is going above 90ish and your fans aren't coming on, this would suggest thermostat not opening or water pump inoperative. Give your top radiator hose a feel when the temp starts to rise above normal. If it's cool enough to hold on to without burning yourself, then chances are, your coolant isn't circulating properly and this is why your fans aren't coming on.

Your engine temp measurement for the temp gauge is taken from a sensor on the engine - so if the gauge is high and no fans, the hot coolant is not getting to the thermo switch on the rad.

On a more serious note though - this problem may well be linked to your choc mousse. If you have oil mixing in your coolant, this could be an indicator of poss head gasket problem. Don't want to worry you, but it's worth thinking about if water pump and thermostat check out ok!

Hope i haven't gone on too long there

Steve-o

[h100vw]

On a more serious note though - this problem may well be linked to your choc mousse. If you have oil mixing in your coolant, this could be an indicator of poss head gasket problem.

A cheaper thing to check before pulling the head off if you have oil and water mixed, is the heat exchanger on the block. They can corrode through and cause the same symptoms as a duff gasket but cost a fraction of the money to sort out.

Gavin

[Bora Sport]

Well spotted and a good tip. A very likely scenario however if it has gotten too hot because the fans aren't coming on it could still mean bigger problems.

[syncro]

The fans have no relationship to the ignition switch.

The oil cooler is a known problem, especially if you don't use G11/12/12+ coolant.

[WA Euro]

Think you're right there, but my understanding of the VR6 is that when you switch the engine off, the elec water pump kicks in and if the mech water pump had failed colder coolant would still be in the rad. Elec pump would circulate the hot coolant round to the rad - and switch on the fans??

[pommy_golfer]

All good guys,

I found the perfect tool for the job, will take a pic of it and post it, it cost me only 10 bucks from bunnings and worked like a dream.

The fans kick in when the temp gets to 100 degrees. Is that the way it should be?

its not overheating now anyway so me happy!