Today after an oil change I took the truck out for a ramble and as I as coming back at low speed it overheated. I picked up speed and it cooled back down...I suspect its the fan clutch. What is the easiest way to test the fan clutch?

Mahalo

 

Just let the engine idle and see if it kicks on by itself as it should. If it doesn't after reading about roughly 210 degrees then it's either the electric fan motor or the relay switch.

 

If you have a stock clutch fan, with the engine off, try to spin the fan by hand. If it keeps spinning and/or spins really easily, it probably is the fan clutch gone bad. Usually with a good clutch, you will get some resistance from the fan when you try to spin it and it won't spin very much before it slows and stops once you let go of it. Also check it for oil leaks that may come from the front side of the clutch, facing the radiator. See if the fan wobbles also by trying to move a blade front to back. It shouldn't move but only slightly if at all. Also check for any obstructions in the air path to the radiator. Could be that something got in there. Be very careful with getting the 2.9 too hot! The stock heads don't like it and will crack very easily from getting too hot. If you have electric fans then go with what sfcwoodret said. Let us know what you find.

 

The blade free spins so I am going to pull it and replace it. Thanks guys I appreciate it!!

 

First off, go outside and feel how the fan spins. Then start your truck, let it run for a bit (the hotter the better), shut the truck off, then feel the resistance of the fan. You shouldn't really feel much resistance when the motor is cold. On the front of the fan clutch is a bi-metalic strip that is coiled up. It measures the temp of the air passing through the radiator. As the air gets hotter, it increases the resistance between the shaft and the blade, causing the blade to spin faster.

In other words, you can't really check to see if your fan clutch is bad on a cold motor. You can look for the obvious... a bunch of crap, gunk and grease on the front of the clutch, indicative of it blowing its guts up.

 

Thanks traxx I"ll check it out!!

 

So I got it all apart...the fan has cracks in it and I figure I should probably replace it while I am at it. My local parts stores don't stock a replacement, they want to sell me a electric fan replacement...Any idea on where to get one? I googled it and everyone else wants to sell me an electric one as well...

 

Na, just put an oem back in. If you can get one from the autoparts store, just hit up a salvage yard. That is, assuming they have salvage yards on your side of the pond.

STan

 

They do but they are usually a rip off...the search continues