yet an other case of over heating

Hey guys,

First a happy Memorial Day Week end to you all! Enjoy.

Now the issue, my car just started over heating a few days ago, so today I did the "start the car cold with the radiator cap off" test.

Water did not move... Nothing... After a while it started to over flow with hot water so I'm guessing it got hot but still did not move right?

My question is, how do I know if it is the Thermostat or the water pump which does not work anymore?

Maybe by changing the Thermostat and seeing if it changes anything? Just asking before moving on to that phase to be safe?

And is it as simple as it seams to be to change the thermostat?

Thanks for the help!

Cheers

 

Yes change the thermostat. Do not over tighten the bolts or you may crack the housing.

 

great, thanks, I'll do that tomorrow, which temperature thermostat should I take? 180?

 

take the one in it out and fire it up that will tell you if it's the T-stat. 180 should be fine.

 

cool tip, should have thought of that haha

Always the simple tricks which are the best

 

reason for this...once I removed a bad T-stat and replaced it with a bad one. was still chasing overheating problem two weeks later. backed back up to the T-stat.

 

makes sense!
Thanks for the wise advice then. I will def check all that tomorrow.

Cheers

 

Well if your system is marginal as far as capacity, get a 160*, that'll open faster and let the system get a jump on the temps sooner.

 

"my car just started over heating a few days ago."

I think we need to find the problem and fix it...

 

Well we're still waiting genius.

 

Do the heater hoses transition from warm to hot before the radiator starts to overflow?? If so the pump is operating and you probably have a stuck thermostat... Also be sure the lower radiator hose isn't collapsing which would block flow from radiator back into engine...

 

Thanks guys for all the tips, I now have time to check this out so in a few hours I will / should have an answer

 

so I took the old thermostat out, tested the system without any, water is flowing!!!!

Got a new one, put it in, water is not flowing anymore, thought it was a faulty one so I got it out of the car, dumped it into boiling water to see, it's working, then I looked closer, they sold me a 195°F one, I'm guessing it's too high and does not open soon enough?

 

Now days a 195* is the norm(actually has been in many US vehicles since the mid '60s)...

Assuming a good pressure cap, that should work OK but engine will run hotter than a 180*...

BTW there will no flow till the T-stat opens and then may not be noticeable as when slightly open the flow is so small may appear still... As engine gets hotter it will open farther(A 195* is not fully open till around 205*), at that point there should be movement... For this reason you may want a 180 vs the 195...

 

Thanks Tom, heading to my parts shop now, hopefully the Comet will be on the road again today!