Overheating


#1

I have a 2005 Durango, ~142k miles. The end of May, I had to get the transmission solenoid replaced, which may not be relevant. About 10 days later, the car started overheating when idling. There was a crack on the radiator neck, by the cap, and I had to get the radiator replaced, and the thermostat. The shop said the fan was wobbling, and they replaced the fan clutch as well. The fan was a lot louder than it had been, the mechanic said he had put in a higher performance fan in and maybe that was why, and offered to put in a lower performance one if I wanted. I declined.

Six weeks later, it started overheating while idling again. I brought it back, and the water pump was out. By now I was checking the temperature gauge constantly when idling, and it never quite hit the center until suddenly after 4 weeks, then it suddenly started overheating while idling again. I brought it back again, and they couldn’t find any problem except he said the radiator was about a cup low, and maybe there had been an air bubble.

I’ve been constantly checking the temperature gauge since, and it once again never quite hit middle until 2 days ago, and now suddenly it’s overheating when idling. I checked the coolant level after it had been sitting for a couple hours (and I had only driven it for about 10 minutes so far this morning, before that. I can’t take it in until Monday now, just wondering if there are any ideas out there. I’m afraid there is a blown head gasket or something, but if so, why would it run so well for an extended period, and then suddenly start overheating again, twice now? They haven’t done a compression check.

In case this is relevant, every few days the car will just stall out when coming to a stop, and sometimes the idle seems rough.


#2

This is a bit of a longshot. Next time it’s overheating pop the hood and see if the upper or lower radiator hose is collapsed. If it is try a new radiator cap. It’s the only cooling system component you didn’t mention as having been replaced. Without proper pressure in the system (about 15 PSI) the water pump, drawing directly on the lower hose, can cause it to collapse.


#3

Classic blown head gasket. All is OK until the slow leakage of combustion gases produces a big enough bubble in the cooling jacket to affect circulation.