Overheating 3.0...

[Ranger_Dan]

Well I've had this truck for about a month and 2 weeks ago it began to redline in traffic, i figured it was because it was really hot that day, so i shrugged it off because as soon as the light turned green it would come off of redlining, Well i went away for a week and have been driving it today, it overheated this morning in just about 5 minutes, i turned off the truck and found the fluid in the reservoir boiling so i let it sit for an hour and have been driving around again, it hasn't redlined for a little while but it gets dangerously close.
What does this point to? thermostat?

Thanks
Dan B.

 

[fivespeed3.0]

I would check that the coolant is really 50/50 coolant and not just water

 

[Rearanger]

Well I've had this truck for about a month and 2 weeks ago it began to redline in traffic,...What does this point to? thermostat?

Tough to say since you probably don't know the maintenance record. When I buy a used vehicle I usually change all the fluids first thing. Stat probably the cheapest place to start. What condition is the coolant in? Does this have the original clutch fan? If you put the truck in neutral and rev the engine does the temp drop? If you turn on the heater does the temp drop?

 

[McCormack]

Make sure your radiator's exterior is clean and replace the thermostat, and if that doesn't do it then your water pump impellers might be worn or you have possible head gasket issues.

 

[Ranger_Dan]

well i made sure it was 50/50 with a hydrometer, the radiator is clear so i think i will replace the thermostat and fluid next.
I'm pretty confident the fan is original, and yes the engine temperature drops when i rev the engine and i found it too hot to turn on the heater, Thanks for the help guys.

 

[Rearanger]

I'm pretty confident the fan is original, and yes the engine temperature drops when i rev the engine.

I'd test the clutch fan, just Goggle "testing a clutch fan".

 

[Ranger_Dan]

gentlemen, always check hoses.
some crap has clogged the hose from the reservoir to the thermostat.
So I've decided i will flush and replace the fluid.

Thanks for all the help!
Dan

 

[Rearanger]

some crap has clogged the hose from the reservoir to the thermostat.

Do you mean from the rad cap to the overflow reservoir?

 

[Ranger_Dan]

the reservoir in front of the wiper fluid, i thought that was the main reservoir.

 

[Rearanger]

the reservoir in front of the wiper fluid, i thought that was the main reservoir.

Well, that's the overflow reservoir where hot expanded coolant is held until you shut the engine off and the engine cools. Once the engine cools this coolant is pushed back into the cooling system. This reservoir helps maintain a full system and provides some backup to a leaking system. If the hose was blocked then expanding coolant would probably flow out the rad cap, but not be replaced when the engine cooled. If this line is blocked it may be a hint that your rad is also partially blocked and hence not cooling at 100%.

Have you been checking the coolant level when trying to trace this overheating? I doubt unclogging this tube will fix your overheating.

 

[Ranger_Dan]

it partially helped, but now it just takes longer to overheat/ it really only overheats when I leave it idling now. The level seems to always be above the line in the reservoir.

Dan

 

[Rearanger]

it really only overheats when I leave it idling now.

Idling is reduced airflow and reduced coolant flow. I'd go with reduced airflow right now - either bad clutch fan or clogged rad (or both). Have you done the clutch fan test yet?

 

[ben@g2g]

I'd pull the water pump. One of our F350s was doing the exact same thing. There was only 1 impeller blade left on the pump(should have had 6). So it moved water, but only at higher rpms, and not very well then either.