Temp guage reads normal, coolant boiling from radiator?

[takaminegenie]

Where's the flaw? Temp guage displays in the normal, just installed a new aluminum radiator ($130) and left the thermostat out for past overheating problems. Wanted it to run cool for a while. But the antifreeze is boiling out whenever i crack the cap on the radiator. While running the radiator is cool to the touch, but is scolding hot after sitting off for a few minutes. HELP!

 

[NOTAJP]

You need to run a thermostat so that your engine will continue to run at the right temp consistantly. You should be running a 50/50 mix on your antifreeze. At 50/50 coolant won't boil until 220 degrees. The reason why your coolant is boiling over after you open the cap is that pressure will bring up the boiling point another 8-10 degrees. So your coolant can run at 230 without boiling under pressure. When the engine is running, you have the water flowing and the fan pulling air over the fins of the radiator that is cooling the water. When the engine is off, water is not flowing and air is not cooling the water. It will be hot to the touch for a while after the engine is shutdown. You might want to make sure that you have a 50/50 mix, thermostat is installed correctly and in good working order, no air trapped, fan and clutch are in good shape, and your cap is in good condition. If you have anymore questions, let me know.

 

[mcgyver ky]

thats right

in a nut shell if the water is at full flow the fan doesnt have a chance to cool it off so it boils,

very well put NOTAJP and well worded

 

[NOTAJP]

Re: thats right

Originally posted by mcgyver ky
in a nut shell if the water is at full flow the fan doesnt have a chance to cool it off so it boils,

very well put NOTAJP and well worded

Thanks Man, I try....