Non-SVX overheating issue?

[davew833]

I'd post this over in the "Not Exactly SVX" forum but it doesn't seem to get much traffic these days...

My mom's '94 Chrysler LeBaron overheats intermittently, especially if she drives it around town (stop & go traffic) late afternoon. It's the Mitsubishi 3.0 V6. I've replaced the thermostat and drained and refilled the coolant, which didn't seem to make much difference. It's not losing any coolant, and I don't see any evidence of oil in the coolant. (No "milk shake" in the overflow tank...) Can anyone suggest what I might check next? I'm just hoping I don't have to do head gaskets like I did on my first SVX!

(Sorry about the non-SVX post!)

[Subix]

The radiator cap itself? On my SVX, it was bubbling out slowly at the top losing pressure most likely causing air bubble making it over heat.

[XT6Wagon]

radiator cap should be tested or replaced as a 1st step in any cooling issue. Boiling point of the coolant is MUCH higher at 14psi or whatever the factory pressure is. Its also required in some engines to prevent localised boiling even when the avg coolant temp leaving the motor is well below boiling. A little localised boiling done right increases the cooling of the engine... Most engines don't manage that happy little feat and go straight to steam insulating the cylinder walls from the coolant which can cause the motor to overheat with coolant below boilingpoint.

[1986nate]

I'd take a look at the water pump. Head gaskets are extremely uncommon to fail on that engine. If they are bad though, they're extremely cheap and easy to replace. Probably under $100 for a head gasket kit for that.

[davew833]

Well, I replaced the radiator cap and that didn't seem to help. Do radiators get plugged up these days or should I proceed straight to replacing the water pump?

[1986nate]

It's possible. Also double check the radiator that the cooling fins are falling apart. I've seen that on a few cars.