overheating at idle!!!

[slapthefunkyfou]

I can drive around all day long and as long as I'm moving at a good speed like 25 mph or faster, then I have no problems. But at idle, the temp goes way up. I do know that having airflow around the radiator helps alot to keep the temp down and I had always thought that the fan always turned with the engine, but after searching this topic, I found out that some x's have a fan clutch.

So my question is, does a '91 have a fan clutch? And could this be causing my overheating problem?


The other thing is why do things like this happen only when your out on the trail? I could drive for maybe 5-10 minutes and then had to let the engine cool down for 20 minutes. It took me forever to get down the mountain.

 

[MrShorty]

The 4.0 OHV always had a fan clutch on it, as well as the 2.9 which preceeded it. Your symptoms seems standard for a bad fan clutch. Best test for fan clutches I've found is to take the fan clutch off, rotate the little spring 1/4 turn CCW (to disable the freewheel feature) then reinstall and test drive. If your overheating problems go away, then you've found the problem.
"The other thing is why do things like this happen only when your out on the trail? I could drive for maybe 5-10 minutes and then had to let the engine cool down for 20 minutes. It took me forever to get down the mountain." -- Same thing happened to me above Fillmore. If I would have had my fan clutch wrench with me, it would have been simple to disable the freewheel feature of the fan clutch and I would have been fine. But I didn't have it with me and so I was irritated (fortunately that's all). Next time, that fan clutch wrench is in my toolbox.

 

[Creager]

man ya gotta speed up, boats gotta be going fast so they can use the water for cooling

EDIT: wait wrong forum

 

[jimbo74]

it sounds like either a bad thermostat or a jacked up fan

 

[msmith65]

I did the spring-rotation test and found my clutch isn't working well at low speeds.

FYI, if you have a pair of 90-degree bent-nose pliers, you should be able to pluck the coil's end out and turn it without removing the fan clutch first. You will have to move the shroud (two bolts) back to reach the coil.

x-posted

 

[Glacier991]

Yeah this fairly screams fan clutch.