New guy, Matthew.

[Matthew Chanowski]

I'm a new guy to the form but I just recently purchased a 2004 Explorer 4.6 L 2 wheel drive and I'm having overheating issues. I have change the water pump put a new serpentine belt on it flush the coolant put in OEM Motorcraft coolant. It will not overheat with the AC on high at idle. I sat in it for 45 minutes and it wouldn't overheat the moment I put it in drive and move down the road I get a few miles it starts to overheat again. Just about to change the transmission filter and fluid was hoping someone had some kind of insight. Please and thank you.

 

[974X4BLACKSPORT]

I am not familiar with the 4.6 engine, or it's cooling system, I have seen on other cars before and, something easy to check is sometimes the upper radiator hose can collapse when the engine speeds up and the water flow throught the hose also speeds up, like when you start moving from sitting, this will restrict the cool water going back into the engine.

 

[Matthew Chanowski]

I am not familiar with the 4.6 engine, or it's cooling system, I have seen on other cars before and, something easy to check is sometimes the upper radiator hose can collapse when the engine speeds up and the water flow throught the hose also speeds up, like when you start moving from sitting, this will restrict the cool water going back into the engine.

So maybe replace hoses.?

 

[974X4BLACKSPORT]

I would say if theyy (coolant hoses) are original from 2004 (14yrs) old, It would not hurt to insstall new ones, at least for maintanace reasons.

 

[Matthew Chanowski]

Thank u

 

[BrooklynBay]

Welcome to this forum! Did you replace the thermostat?

 

[Matthew Chanowski]

Yes. I have replaced the water pump the thermostat flushed the radiator and all the fluids, filters including transmission and oil. I think that maybe I've got a plug somewhere in the radiator. Because if I let it sit in the driveway and run with the AC on high and like you know all that kind of stuff and heat coming out of the heater I mean it stays in temp when I start to drive it that's when it overheats and it doesn't overheat immediately