Coolant boiling in the overflow tank

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Cajun
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Coolant boiling in the overflow tank

Post by Cajun »

My engine seems to be running a little hot but consistant around 210 according to the dash gauge. About 3-5minutes after I turn off the engine the coolant boils into the reservoir and the temperature gauge climbs to have way between the 210 and 260 degree mark. No water in the oil and no bubbles while the engine is running. Any thoughts.

Thanks guys!
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HenryJ
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Re: Coolant boiling in the overflow tank

Post by HenryJ »

First thing that comes to mind is bad head gasket. There is a hydrocarbon test kit that can check the coolant for combustion gases.
Another thought is the plugged cat. Overheating is a symptom.
GL

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
"Speed is just a matter of Money - How fast do YOU want to go?"-Mechanic from Mad Max-
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Cajun
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Re: Coolant boiling in the overflow tank

Post by Cajun »

Just replaced the cat yesterday. Thought that changing the cat would solve the overheating issues also. Have had a head gasket and intake gasket issues before but both times I got an SES light with it. Thermostat?
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Re: Coolant boiling in the overflow tank

Post by Cajun »

I changed the thermostat and radiator cap and did not get boiling over after the 30 min test drive. I the engine temperature did rise after I turned the engine off the temp did rise to 225 according to the temperature gauge on the dash. Does that sound normal?
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Re: Coolant boiling in the overflow tank

Post by HenryJ »

Heat soak is normal. The stock gauge, IIRC does read a little higher than actual temp. Sounds like you may have it solved?

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
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Re: Coolant boiling in the overflow tank

Post by JaVeRo »

I would take the plastic shroud off and check the area between the radiator and the AC coils, suck the bugs out with a vacuum cleaner, wash or blow it out. It might not help but it sure can't hurt.

Some people never look between there.

James
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Re: Coolant boiling in the overflow tank

Post by Cajun »

Turns out the radiator had restricted flow. Replaced the radiator and hoses and everything running cool now.
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Re: Coolant boiling in the overflow tank

Post by HenryJ »

Cool. Literally 8)

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
"Speed is just a matter of Money - How fast do YOU want to go?"-Mechanic from Mad Max-
If at first you don't succeed - Don't take up Skydiving!
- ThunderII KE7CSK