Once again, sorry this isn't a Mustang but it's a straight six so I'm asking you guys,

Alright, this is for a 1992 F-150 4x4 with the 4.9L 300 C.I. I6

The motor seems to want to overheat when you're not moving. Example: Was just driving it to try it out since had the new exhaust on, runs great. I kept an eye on the temp actually, ran just barley over the cold mark on the dash. Go to back in, decide I'll go up and down the driveway one last time. Do that, go to park and notice the gauge is just before the Red Hot mark on the dash. So, go drive it on the main road again, once moving the temp drops back down the cold quickly. Once you stop moving it goes back up quickly. How is it dropping so low, then flinging back up so high right away ? It needs a coolant flush bad, the coolant is brownish, some brown crud on the radiator full neck area. Any suggestions ? Also, fan appears to spin fine at idle.




~Thanks.

 

maybe the water pump? i would definatly flush out the system

 

Flush it. Does it have a clutch fan? Check that the fan is drawing air through the radiator. Just hold your hand in FRONT of the radiator and feel for air movement.

 

Well, it's going to get a flush tomorrow. So I suppose we'll see what that does. I'm hoping the radiator isn't trashed.