my engine is overcooling HELP!!!

[mwood1985]

i have a 2001 4.0 and im having a OVERCOOLing issue.the temp guage bearly rises about the c mark on the guage. i ran it 60 miles at 70 miles an hour and it ran just fine. i have a body lift on and havent finished putting the front bumper on but it ran normal til i shut it down then cranked it an hour later. i checked the radiator and the coolant is definantly not overheating. im seeing a slight amount of metal floating in the coolant. the waterpump is operating normally so im assuming the thermostat is stuck open. any suggjestions on how to fix this problem?

 

[bcost882]

new thermostat. if you do see metal in the resevoir you might want to make sure it came from the thermostat and not something else. im not positive but i would think that it would eventually get warmer as time went. but otherwise check that

 

[Big Jim M]

When you lay your hand on the top radiator hose after a five mile or more trip is it HOT? Does the heater put out hot air? If the answere is yes then your problem is the sender for the gauge.. If you take the cap off and when the engine is running you have a big flow evident when the engine is cold then the thermostat is stuck open..
Big JIm

 

[mwood1985]

the top radiator hose is hot to the touch the heater works fine the guage just dont wanna move to the normal area when warm. so should i toss a new thermostat in and how do i fix the sending unit? can i drive the truck until i can get it fixed? i still have flow throughout the engine

 

[stangdroptop351]

sounds like a bad gauge or a water temp sensor if the top hose is hot and you got heat in the cab

 

[mwood1985]

it worked perfectly for a 60 mile drive north i shut the truck off for an hour to go shooting then cranked it to drive home and on the way south noticed it wasnt heating up according to the guage but i DID have great heat

 

[Big Jim M]

So go get a new temp sending unit.. Job done.
Big JIm

 

[bcost882]

see i can deal with that except the metal particles in the resevoir.

 

[Big Jim M]

Drag a few out and put a magnet to em.. I never saw metal fragments FLOAT...but you seem to have some that do.
Big JIm

 

[mwood1985]

idk the radiator is the original one far as i know . should turn 140k miles sometime this week. hopefully lol. thanks for the input guys ill post up if that solves the problem

 

[Earl43P]

IMO, the logical thing is to replace the thermostat ($8).

It regulates the engine temp, which indicates low. Get a new gasket too.

If that fails to fix it, worry about a temp sensor. Throw a piece of cardboard in front of the radiator and drive for a few miles. If the temp gage rises with less airflow, sender is good, thermostat is bad or fan clutch is stuck engaged (you'd hear that).

 

[modelageek]

at 140k it would not hurt to put a new t-stat in. I would only put a motorcraft in, buts that just my opioion. just so we dont get confused. the water temp sensor is for the pcm and the temp sensor is for the gauge. you want to change the temp sensor.