Bertrand Daoust

Hi all,

I had the car flat beded home today after I had a high coolant temperature warning while driving it.

The engine indeed was very warm.
Coolant was very hight in the expansion tank.
Very close to the coolant cap.

I'm thinking about a bad water pump or a blown head gasket.

Once at home and the car cooled, I noticed that the coolant level in the expansion tank was way too low. About 2 inches lower than the level mark.
No trace of coolant anywhere I can see (for now).

That makes me think that I may have a blown head gasket.
The car has 126K km.

Am I right to think that's the problem or am I missing something?

But...

Once at home, I filled up the coolant tank and started the car.
The temperature went up quite fast (5 min. maybe) very close to the red mark.
While waiting, I put the blower on warm and didn't get any heat at all. No cooling fans either!
Upper coolant hose quite warm, lower coolant hose cool.
No coolant circulation. That makes me think that I may have a problem with the water pump.

A very important thing here is that I have a Gardian WP.
It might be that the rubber coupler let go.

BTW, the overeating warning happened about 5 minutes after I smashed the gas pedal to pass a car in front of me.

If it's a problem with the pump, why did the coolant went down in the tank and don't see any trace of it outside the engine?

What do you think guys?

Thanks in advance.

I think I'll need to drop everything in front and take a look at the pump first.

NoVector

Bigger brains than mine, but sounds like circulation to me. If not wp, maybe thermostat(?) The fact that it happened after flooring it makes me think the former and not the latter.

The coolant may have blown out the overflow hose when it was uber hot as you were going down the road..

Any white smoke out the tailpipe? Does your oil look like chocolate milk or any signs of oil in the coolant overflow tank?

Speedtoys

Before this turns into a 96 post thread about what it isnt, start with the simple high likelyhood stuff.

The radiator cap AND thermostat and BOTH thermostat seals need replaced first. Then reassess.

FredR

Bertrand,

You might be better served initially by trying to do a pressure test at 14 psig on the cooling system. A failed impeller will likely [but not necessarily] hold pressure whereas a head gasket should not do so.

If the impeller drive has failed somehow the engine will over heat quite quickly- I have had that happen twice when the plastic impellers came off. If your heads have never been off then a head gasket failure is distinctly possible given the 26 years of age. And indeed- the thermostat should be investigated.

Good luck whatever the problem may be.

Fred

Bertrand Daoust

No white smoke as far as I know.

I checked the oil and coolant and no sign of oil in coolant or coolant in oil.
That's good I think.

Like you said, maybe it went out while driving.

Thanks.

Bertrand Daoust

The thermostat, seals (front and rear), cap, tank and all coolant hoses were changed last year.

If I go all the way to the water pump, and I think I will, I'll double check everything there.

Thanks.

Speedtoys

The Tstat can still fail...best of luck.

oups59

Bertrand,

I am sad to hear your problem. What concern me the most is the drop of coolant in the expansion tank. It has to go somewhere. Is a bad tank cap can cause the hot coolant (vapor) to escape? You can verify if the hood has some coolant residues near the expansion tank?

I have a quick gasket tester if you want to try that?

oups59

If the tank overflow is working properly, you should see some coolant from underneath .....

SeanR

Betting the guardian coupler has let go and is spinning freely.

Bertrand Daoust

That's what concern me also.
The coolant had to go some where.
Didn't find anything yet under the hood. And nothing on the ground either.
I'll try to find a tester around and test the system. If I can't find one, I'll get back to you. Thanks for the offer.
I'll know better when I'll lift the car and remove the belly pan.
Looks very much like this is what happened.
Will know for sure when I'll get to the pump.
We'll see...

Thanks guys.

928nut

Sorry to hear this, brother Murphy never takes a break.
I am inclined to think it is a WP problem, from the way it developed - after a rapid increase in RPM. However, I would start by eliminating the "easier-to-do" possibilities and if they check out OK, then it is onto the BIG job. I feel your pain, if I can be of any help, let me know.

Bertrand Daoust

Thanks for the offer Jan.

MainePorsche

Sorry to hear Bertrand.
If the Guardian did 'let go', I bet your happy you had one.

Bertrand Daoust

If the impeller bearing seized or migrated, it surely saved the car.

If the coupler did let go, I surely want to know why.

The pump was installed in 2010 and removed for inspection in 2014. Didn't have any problem with it.
I maybe put 35k km on the car since 2010.

Thanks.