loced27

Car started to over heat, then got on highway (after letting it cool down at a friends) and it was over cooling looking at the thermometer. IF a fail safe thermostat is stuck open will I need to replace it to get it closed? or do they close themselves? This is a new thermostat that is fail safe just 2 weeks ago.

Another thing. What caused it to over heat and make my thermostat stuck open in the first place?


Things already done :
Changed lower intake manifold
Thermostat
Waterpump
Radiator cap
oil

Mechanic said heads gaskets were good so no needed to change them.

Things to note:
Smells like radiator fluid inside the car when over heating.
Runs real quiet never over heated before strong engine.
103k miles.

Should i get my radiator checked first? Or head gasket checked first?

No water in oil, Water is clean and green.
I open the radiator for the past 3 days and watched it warm up before work. Things I noticed where no bubbles and the water level goes down and then up when revved and no bubbles. so but then I was told it needed a new radiator cap and I replaced it now it started to over heat.
If you look very hard you can see the oil color in the green but it may be from not replacing the coolant from last lower gasket manifold change. Should I flush the coolant and see if it gets oil again?
Any help would be greatly appreciated and I will give + rep to the answer that helps thanks.

SWHouston

Though I've never used that type Thermostat, I hear that once it's tripped open, you must replace it. No auto reset !
Ref:
https://chevroletforum.com/forum/tah...28/#post227386

But on your orignial overheat problem...
You've done just about everything. The only other thing I can think of is that something is clogged, not giving you enough area to get the temp down.

Also, it's not too unusual to smell coolant inside when you're overheating like you have, IF you don't see any wetness inside, you probably are ok there.

You might do one other thing...
Go by a Rad Shop, and have them "sniff" the headroom in the radiator. That'll tell you if you have a combustion leak into the water jacket, which could cause an overheat.

kevinkpk

Way I read it, looks as if the tstat was the problem with overheating since now it has failed open, and you can't get it to warm up. If it is a fail safe, least the one I have says it will have to be replaced.
I have one to replace in my lumina, but since son has my suburban it besides my 70 delta is the only vehicles I have, so I'll have to wait on the suburban to come home.

loced27

I could not get the lower thermostat bold off. I was trying to use a small 13 mm wrench. What type of wrench should i use? Top one is stuck too.

loced27

I got the thermostat off, To my horror I found the thermostat was gutted. I put in a brand new one, The car instantly started to over heat with it on, It would not take alot of radiator fluid only 1 gallon then got full and start spitting it out far. I immediatly suspected the water pump but it is new and runs good still. The fans turn on.

I put the old gutted one back in and it runs over cooled again.

I put the heater on full blast to the floor. Then revved the engine via accellerator cable, then filled it up much as i could and put cap on. The resovoir has fluid in it now when it did not before. This is a new radiator cap too.

I am suspecting the radiator? Does anyone know if it sounds like a radiator problem? Or why will the car over heat unless it has a gutted thermostat?

junkman104

First you said it was a new thermostat, then you said it was gutted. Sounds to me you need to find a new mechanic. Also it sure sounds like head gaskets to me. What engine is it?

loced27

Sorry, Yes. I did put a new thermostat on. Then after it immedialyt over heated. I had to remove the new thermostat and put the original gutted thermostat back in. Yes everyone is saying head gaskets but There is a gutted thermostat in there which causes it to over cool so idk if it is that or head gaskets. It's a 3.1 GM engine. Thanks.

Yes, the mechanic that put on the lower manifold gasket. When I called him to tell him I need to get my thermostat changed he said' he come over and never did. So I had to call this other mechanic and we found the gutted thermostat. Which is probably why the first mechanic did'n't show up like he said he would cuz he knew he did that(put in a gutted thermostat). But We don't know why he put the gutted thermostat.

GMcerttech

test the heads with a simple test you can get at just about any parts store i beleave its called a combustion leak test comes in a kit with fluid a tube and a rubber cone. it will tell ya if you need a head gasket or not. you also may want to check your heater core see if you have fluid on the passenger side under the dash. reason i say that is you said you smelled coolent in the cab.