weird overheating problem
 

I just changed the thermostat the other day and It turns out it was a 195... now I believe i have the 50/50 coolant in their and the car runs fine but then jolts up to 230 and then depending the car will run there for a while or bobble between 210 or so... I believe the thermosta is not opening because their is no pressure at time in the upper rad. hose and my overflow tank is full... any advice will help alot... I mean it is the dead of winter in NY and is cirrentyl about 10 deg out so it shouldnt be overheating... is the thermostat frozen stuck or what?!!?!

A new thermostat can stick. Why did you change it in the first place? Was it overheating before?

Did you put the thermostat in, facing the right way? The bridge, "Pointy side" points to the radiator, or toward you when its seated.

Does the water try to boil out the radiator cap, when its hot? Or blowing back into the overfill?

Frank

I agree with the above statements. If you have no water leaks anywhere, then the stat is either stuck closed or in backwards. You can test it by removing it and placing in in a pan of water on your stove and watch as the water heats up to see if it's opening.

Dave

First of all 50/50 coolant/water ratio is way to high. I wouldnt use any more than 30% coolant, I would actually use about 20-25. Here in fl I use 10% coolant. Coolant will retain the heat more so than the water will. Try reducing your coolant ratio a little bit, and also check the thermo. Check for any leaks also, as the cooling system will only work correctly if it is pressurized.

When you changed it all out you abviously lost some coolant. When you filled it up and topped it off did you let it warm up and make sure it started circulating before putting the top back on? Usually what happens is once the thermostat opens up the coolant level goes down because it fills up the air that was gain when the change was made. pop you rcap back off and make sure it is till topped off. Good luck, if it's not that then like they said, the thermostat is most likely in backwards, don't worry it's a common mistake!;)

Your temperature sending unit might bad. It can also be an electrical problem. My temp needle use to climb a bit when I turned on my headlights. Does that stove trick really work? I thought that the pressure created by the heat of the closed system pushed open the diaphram connected to the thermostat spring. Boiling water in a open pan will give you the heat, but not the pressure.

The stove trick diffinately works.. though for the cost of a thermostat... hardly seems worth the effort of testing it... but I allways throw the t-stat I take out of a car in some boiling water just to check... though I often find that it works and there's some OTHER reason for the overheating... could be water pump could be in backwords, could be gauge, could be not enough coolant.. though you should get a light for that
-as

My false overheating problem went away after I removed my sending unit (top of manifold) and used sandpaper to remove all the buildup from it. I guess the buildup acted as an insulator, causing the electrical resistance to vary, thereby giving false readings. My guess. A loose ground somewhere or weak charging system, bogged down by accessories (such as a fan blower motor - you said it was cold out) could possibly also vary resistance in the system. Electrical problems really suck. Hopefully it is just something simple like the thermostat.

Are you nuts??? LOOK at his location.. He NEEDS a 50% or close to it with the temperatures he could encounter in HIS area... Also the effect of 50% vs 30% is VERY small on the temp it would run.. I RUN 50% in TEXAS and we have 106 degree days in the heat of summer with 100 percent humidity.. WITH no overheating problems..


As for his problem it sounds like he has the thermostat in backwards (most likely) or a bad new thermostat(not as likely) , or a air pocket.. (make it easier to get air pocket out of system by drilling a small 1/8th inch or so hole in the edge of the thermostat.. )

BigT

Coolant's main purpose is to lube up the water pump and protect against corrosion. Explain why nascars run absolutely NO coolant in their engines, just straight water. Water retains less heat than coolant, as I stated above.

Ok..


Ready to go to school:D

Coolant has several functions..

One is to provide freeze protection.
Two is to provide a RAISED boiling point (in conjunction with a pressure cap)
Three is to help provide corrosion protection and lube water pump etc (as you mentioned above..)

HOWEVER,
You were indicating that BECAUSE of his high coolant concentration it could/would cause the problem he has with MAJOR OVERHEATING. (HOGWASH!!!:rolleyes: )


ALSO,, you mention nascar.. well i am gonna give you the REAL reason they and DRAG racers run straight water MOST of the time.. Antifreeze when lost on a track surface due to wrecks, failures , or any other reason is VERY difficult to clean up .. It leaves a DANGEROUS slick spot that can contribute to mishaps for the rest of the day.. WHEREAS , straight WATER can be cleaned up easily and if any is missed it will simply evaporate.. In this time of enviromentally sound business practices the tracks also like to keep the enviromental impact as LOW as possible. They have enough challenges with all of the "other" fluids that can be spilled..:)

Have a nice day .. Class adjourned:cool:

Tony Davidson
Owner T & A Automotive
Huntington,Texas

coolant info from the man himself


yeah i know i missed a few coolant purposes, thanks for the reminder.

Which is also why most NHRA certified tracks you attend, require a catch can on your vehicle.;)

You missed the point:rolleyes:

All sanctioning bodies require a catch can,, BUT,,, if a vehicle has a wreck.. blows a motor , etc it can cause disastrous problems (ie:wrecks) because of the slick spot that it can leave.. Hell it can even cause a wreck if it dumps coolant and your drive tires/slicks get in contact with it..

And actually NHRA does not want ANY cars to have antifreeze in them.. But it is rarely enforced and would be hard to enforce with all of the street cars than run..

Did I?

The etc part would refer to leaks also right; which in return...

Which is also why....

;)

Yes you did MISS THE POINT !!!

You must be part dumbazz... A catch can WILL NOT CATCH ANTIFREEZE THAT GETS OUT DUE TO A WRECK WHEN THE RADIATOR, GETS BUSTED ETC>>>>:rolleyes: :rolleyes: :rolleyes:

you dont have to use any antifreeze in an engine if you live in warm climates. you can run water but corrosion will set in. Use Water Wetter with the water. It has anti corrisive agents of that of antifreeze in it. Water has superior heat tranfer of any other glycol based coolants.

Why do racecars use it?

1. water is free
2. it evaporates
3. easy to clean up
4. better heat transfer than antifreeze
5. lower engine temperature, you can run more timing

I wouldnt use straight water without a corrosion inhibitor like Water Wetter.

All water pumps that i have put it are sealed bearings. How do you lube a water pump? :confused:

That was actually a very intelligent post :)

Water wetter is one of several products like it that keep the corrosion down.. Most pumps can't actually be lubed, but what can is the seals that seal the water/coolant from coming out around the shaft.. I had already caught that in the original post but thought it was already hard enough getting him to understang the fact that a catch can don't catch coolant from a broke radiator, broken block, blown headgasket, etc...:rolleyes:

I never said it would, obviously it won't when you wreck.

I WAS SIMPLY SUGGESTING THAT A CATCH CAN WOULD CATCH SMALL LEAKS TO PREVENT WRECKS ALSO OK. If I am wrong and that's not one of it's purposes then sue me, I don't think not knowing contributes to being a dumbazz. If it does then why do we have a message forum in the first place? To learn, ask questions and get opinions right?

We're all on the same side here chief.


Yes, very good point, that is exactly what I do since my car stays in SouthEast Texas heat. Water wetter is great stuff. I highly recommend it to everyone.

It was that "know everything attitude" that got me stirred up.. I hope we are on the same side.