Mechanics

WILL THE WRONG SIZE RADIATOR CAP ON THE RADIATOR CAUSE IT TO OVERHEAT

2001 Mitsubishi Galant • 137,000 miles

I have checked everything from the head gasket to the thermostat to the water pump and it just constantly keep overheating at short drives.I have replaced the radiator but not the cap could this be the problem
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Farmmersist
August 20, 2012.




Th cap can be a problem it can easily be pressure checked, but normaly you should have hte whole system pressure checked to see if you have an internal leak. Also disconnect fans if electric with engien off when it's hot place h and in different spots on radiator fins. If you feel a cool spot then ti's probably bad as it should be teh same temp all over.
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Hmac300
Aug 20, 2012.
They call for a 16lb cap and the one that was on it says 0.9, could that cause to over heat in less then 2miles

Tiny
Farmmersist
Aug 20, 2012.
Have you had the radiator checked for internal blockage, a back flush will not show up any blocked core tubes, the radiator must be removed and tanks taken off and tubes cleared of any sediment.

Mhpautos
Aug 21, 2012.
The radiator is brand new.

Tiny
Farmmersist
Aug 21, 2012.
The cap at.9 atm is slightly under pressure but this will not be the primary cause of such rapid over heating, you should have a 1.1 rated cap, possibly a faulty thermostat causing no circulation, water pump impeller corroded away, coolant leaks causing air locks, ensure that these are all not an issue in your case.

Mhpautos
Aug 21, 2012.

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