Overheats then is Fine

[JeffMoss1]

Alright, i can't figure it out.

My engine, when i start it up, doesn't want to flow coolant through the radiator. Flows through the heater core and such, but not my radiator. After driving it a bit, it'll just start to overheat. Right then the coolant will start to flow. (I can smell it, but right when it starts, i can see the temp rise on the gauge and the radiator will all of a sudden be hot. The smell will then go away.

So i figured it was the themostat...replaced it...still happens.

Water pump? Radiator?

Doesn't make any sense to me.

~Jeff

 

[Doc]

I've read several threads here about replacing t-stats. If memory serves me, there is a check ball in the t-stat housing that can stick and cause the engine to over heat. I know you said yours only over heated on start up. It's possible the check ball sticks until the t-stat housing gets hot enough to expand and let the ball loose.

Check through the archive and see if you can find something on the t-stat housing.

 

[highest_vision]

Did you clean out the bypass passage in the thermostat housing? You will have air trapped in there otherwise, likely affecting thermostat opening temps and coolant flow. I over-gooped my gasket and had this happen, had overheating problems for a month or more. Either that or take it back apart if you have time.
James

 

[icanfixall]

What thermostat did you install and where did you buy it??? Any thermostat will fit but we have only one thats the correct one for our motors. Its a Ford or International only part and is 192 degrees.Don't use anything else. The motor will overheat and dye.

 

[highest_vision]

The motor will overheat and dye.

What color?
James

 

[subway]

What color?
James

nice

I agree double check that thermostate, an old pan on an oven with a candy thermometer will do, its the only piece in the system that can stop the coolent flow. dumb question.....you put the thermostate in with the spring facing the engine right....just trying to cover the basics. but i have bought bad "new" parts before.

 

[Exekiel69]

I have the modified fan clutch and I was using the motorcraft t-stat and the engine would still get hot, then I installed the t-stat that came with the kit for said fan clutch and now is cool all the time. This one is set to open at 180f.

 

[Mr_Roboto]

Alright, i can't figure it out.

My engine, when i start it up, doesn't want to flow coolant through the radiator. Flows through the heater core and such, but not my radiator. After driving it a bit, it'll just start to overheat. Right then the coolant will start to flow. (I can smell it, but right when it starts, i can see the temp rise on the gauge and the radiator will all of a sudden be hot. The smell will then go away.

So i figured it was the themostat...replaced it...still happens.

Water pump? Radiator?

Doesn't make any sense to me.

~Jeff

OK. Coolant will NOT flow in the radiator until the thermostat opens. The thermostat stays closed for however long it takes for the engine to reach operating temperature, then cycles open and closed to maintain that temperature.

How do you know the engine is overheating? Is the gauge *******? The overtemp light coming on?

Particularly in a van, any small leak can make the motor smell when it gets hot.

 

[Mont91]

Had a thermostat or two that were bad out of the box. When they were cold they would hang or stick shut. When the motor got good and hot they would pop open, then work fine until the motor cooled off all the way then they would stick again.