if the clutch was fully engaged as you call it you would hear a loud roaring noise when driving like a jet

 

freegdr,

Yeah I thought it spun easy, and it does, but not compared to my truck. The fan in it spins like a top. That's what made me hesitate to put the new one in and ask some more. Either way I'm going to put it in tomorrow and report back. Thanks

 

How did we go from fan clutch to water pump . I don't know is on 3rd.

 

another way to check with mine running i can stick a bath towel up to the grill and the fan will hold it there not a big beach towel a bath towel but seeing it a 2001 replacing it needs to be done

 

This is why I asked.

 

So.. how'd it go? I've been following this thread for a few days and read every post. So just FYI (and to get even) Here's some more reading I looked up for you.

The fan clutch is an automatic device that is often used in a vehicle’s cooling system. So, when the engine is cool or even when it is at a normal operating temperature, the fan clutch will partially disengage the engine’s radiator cooling fan (which is mechanically driven).

This is normally found at the front of the water pump and it is driven by a belt and pulley that is connected to the engine’s crankshaft. This process will then save power because the engine won’t have to fully drive the fan.

But, if the engine’s temperature gets hotter than what the settings for the clutch are, the fan will then become fully engaged, this will then maintain or even lower the temperature of the engine.

You will find that most fan clutches are viscous or “fluid” (the internal friction of a fluid that is produced by movement of its molecules against each other. It is what causes the fluid to resist flowing) couplings that are combined with a bi-metallic (it’s a strip that is used to convert a temperature change into mechanical displacement and it usually consists of two layers of iron and copper) sensory system that is similar to that in a thermostat.

Sometimes fan clutches will fail on you but they are normally quite reliable so this doesn’t often happen. You will find though that a common symptom of the clutch fan failure is the car overheating when idling.

If you have a bad fan clutch, it can also cause very poor performance in the vehicle’s air conditioning system. The reason for this is because the fan also cools the air conditioner’s condenser and that is found directly in front of the radiator.

The other potential symptom if the fan clutch fails is that it will draw the air at a very high rate, so in the cold weather the heating system will blow out lukewarm air and it won’t ever deliver enough sufficient hot air.

It is best to leave the replacing of the fan clutch up to a professional mechanic, unless of course you know what you are doing. But if you are finding that the vehicle is fine on the highway, yet when you are in traffic or you are stuck at a red light and the heat gauge immediately goes up and gets too hot, then it may be time for you to get it replaced.

It is quite a simple process as the fan clutch is simply sandwiched between the can and the connecting shaft. All that would have to be done is to unbolt the fan and remove the clutch. The new one is then installed and the fan re-attached and you will then be on your way. It is advisable to may be do a coolant flush and put in a new thermostat at the same time.
(I hope this answers any questions you might have about your new fan clutch)

 

thanks kjc, i'm going to put it on when i get off work today and i'll let you know.

cheers

 

5/16 or 8 mm for shroud and 13 mm for fan just so ya know...lol...

 

got it covered

 

dont forget the adjustable wrench with wooden hammer...lol...

 

,my bad, good luck with the repairs.

 

ok well here is the update. i got up this morning and went out to replace the fan clutch. it's cold today. old one off, new one on, couldn't really tell any difference between the two in my hands. anyway, cranked the jeep and let idle up to normal temp. seemed to take a while but i don't know if that's how these 4.0's are. after it gets to 210 i can here the efan come on. then i took a little drive through the neighborhood, only about two miles. came back and just sat in the driveway to see if it was cured. after a couple minutes the gauge started to creep up and finally stopped at the line past 210. so i sat for a few minutes longer and BAM! the needle instantly shot up to redline. i sat in park and raised the rpm's to around 1500 and within seconds the temp gauge went down to normal. i guess i can rule out the fan clutch. i really appreciate everyone's help so far. what would be the next thing on the list?

thanks
wes

 

I can tell you that my jeep acts similarly. What I did us replaced the thermostat and that fixed it. The gauge on jeeps isn't very accurate but what your describing is a little extreme so something's not right. I'd say change the thermostat and give it a good flush and check the hoses. How your oil pressure?

 

when you say instantly shot up was the extra cooling fan also coming on at that time

 

Were there symptoms of overheating other than just the gauge? Coolant spew, steam, etc? If not, temp sensor. If so, water pump.