The fan clutch should not free spin when hot, is that correct.

I'm having major overheating problems after new head gaskets, h20 pump, heads shaved, valve job, all new hoses, fan clutch, plugs, wires, cap rotor, etc. I pulled the thermostat yesterday, and replaced the fan clutch today. the radiator has been power flushed twice and looks to be in good shape.

The new fan clutch is acting just like he old one, it has resistance when cold, but when the engine is hot it almost free spins.

Could it be a bad unit, botched head job or what. I'm almost out of money and patience.

 

No, should have resistance when hot, freewheel when cold.

luck,greg

 

What fan clutch did you use?

 

I used the one from AB, they were on sale. I'll be sending it back as it appears to be faulty. Never had a problem with AB in the past.

 

Remember its not AB'd fault its bad.

Read though the "tech section" ontop of the page and you can have a working fan clutch on your truck tomorrow.

 

I searched for "fan clutch" before I started this thread and am familiar with your Chevy Van conversion for the fan clutch. I thought that you were not happy with it in another post, but perhaps I read it wrong.

Anyway, thanks for the help guys!

I'm gonna take it back to the shop that did the head gaskets and see what he thinks. The only thing left to replace is the radiator, and I'm not ready to spend $595 on new one.

 

I had bought a fan clutch from Miami Rovers and either it was bad or a severe duty one, they said it was standard duty, the research I did (Allmakes 4x4 website) said it was severe duty.
It ran constantly.
So I returned it and bought the Chevy one, $50.

 

It's the funniest thing when it comes to overheating. I recently had to move the vehicle almost 200 miles and for he first 100 miles at speeds under 65 in the heat of the day, the needle never moved from just below dead center.

The minute I hit the Interstate and got up to 75, the needle shot up to the red and I pulled over to allow it to cool of. It does cool down quite quickly, in only a minute or two.

That and the fan clutch having more resistance when cold that when hot let me to believe the the thermostat was sticking and the fan clutch is bad.

Since I pulled the thermostat and purchased a new fan clutch, I though I was done with the overheating.

Driving around town it stays nice and cool, but at 65 and above it overheats.

Will a bad fan clutch have those kind of effects on the cooling system, or am I looking a a new radiator?

 

When cold the fan clutch will have resistance because all of the fluid inside it collects on one side and locks it up.
Start the engine, let it warm up, shut it off, try to spin the fan.
If is spins freely you are fine.
When the engine is hot, like when overheating try and spin the fan, is it hard to turn?
If yes it is good.

Overheating at high speed usually means clogged radiator.
There is enough ram air at road speed to keep the engine cool under normal conditions.

So here is what you do, dont drive so freaking fast, these trucks were not meant ot go that fast.
Replace the radiator, shop around, you can get them cheaper than the $600.
Look in the Yellow Pages and find a radiator shop, call them and ask tehm how much to recore a 3 core radiator, dont tell them its for a Land Rover, all they need to know is its a 3 core radiator.

 

Before going for a recore you'll want to have a radiator shop check it out. If the tanks are shot a recore isn't an option. Whether or not they are shot depends on age, how often coolant was changed and where you live.