Fan clutch

[Cj80cruiser]

Should I be able to move the fan with the engine off?

I have read a few of the A/C threads that mention the fan clutch and was just wondering.

My A/C makes a loud skretching sound 70% of the time when I first turn it on and goes away in about 3-4 seconds. I pressed on the belt and it feels pretty tight. My RPMs jump up significantly when turning it on while idling. I also can tell a difference in power loss more than any other vehicle I've owned. I haven't ran ithe A/C that much since I can imagine that belt slipping over the tentioner pulley until it burns up. Assuming that might be my problem. Anyone have a good idea of what to do first?

A/C is extremely cold while driving but not sure about idle since I cut it off due to high RPMs

[Joe Egolf]

I cant move my fan with the engine off

[Tools R Us]

Originally Posted by Cj80cruiser

Should I be able to move the fan with the engine off?

I have read a few of the A/C threads that mention the fan clutch and was just wondering.

Yes you should be able to move the fan with the motor off, but it should have significant drag.

Originally Posted by Cj80cruiser

My A/C makes a loud skretching sound 70% of the time when I first turn it on and goes away in about 3-4 seconds. I pressed on the belt and it feels pretty tight...

Most likely a improperly tensioned and/or bad belt, could also be a bad bearing (compressor or clutch) but they usually make plenty of bearing noise.

[sseaman]

how high are the rpm's with a/c on and idling?

[Cj80cruiser]

I haven't turned it on that many times but the Idle jumps up to around 1000. Then when I turn it off it goes back down to the normal for me which is low around 400. I've been told I need to clean the TB and EGR system.

I can turn the fan easily. I can feel some slight pressure keeping it from free wheeling around though. In other words I can push it but it will only go slightly further than where I take my finger off. Hope that makes sense. I don't know if this would classify as significant drag.

[Cj80cruiser]

I was also looking at "Landtanks Blue Fan Clutch modification for improved cooling operation" and wondered if this is a fix for a worn out fan clutch. I'm a little confused by the whole thing as to what it does exactly besides improve cooling.

[landtank]

Originally Posted by Cj80cruiser

I'm a little confused by the whole thing as to what it does exactly besides improve cooling.

That's all the fan is there to do.

[Koffer]

I 2x Joe about the belt maybe glazed and with a high head pressure when you first turn on the a/c it maybe slipping till it "warms up" the belt (think of drag race cars at the track) and the head pressure comes down when it starts turning

[jonheld]

How about we start with the basics. How old is your fan clutch? If it's over 100K miles then replace it. It is the single most overlooked part of the cooling system IMO. There is no difinitive test for it, it can fail in 3 different ways, and is not expensive to replace.

Replace it with OEM and move on.

[Cj80cruiser]

Originally Posted by landtank

That's all the fan is there to do.

True, but your mod makes a new one or slightly used one better right? It won't fix a bad clutch by replacing the oil and adjusting it I'm guessing.

[Tools R Us]

Originally Posted by Cj80cruiser

... I can turn the fan easily. I can feel some slight pressure keeping it from free wheeling around though. In other words I can push it but it will only go slightly further than where I take my finger off. Hope that makes sense. I don't know if this would classify as significant drag.

Testing them with the motor off can be misleading, but if the motor is cold and hasn't been run in a while, it should take pressure to move the fan and should stop as soon as pressure is stopped. The best way to test them; let the rig idle long enough to completely warm, preferably in the sun on a hot day, with the A/C on and the hood closed. Then open the hood and try to stop the fan. I use ether a rolled up towel or gloved hand, you shouldn't be able to stop it, if you can it's dead.

Originally Posted by Cj80cruiser

I was also looking at "Landtanks Blue Fan Clutch modification for improved cooling operation" and wondered if this is a fix for a worn out fan clutch. I'm a little confused by the whole thing as to what it does exactly besides improve cooling.

Refilling an otherwise good fan clutch is a well proven repair that has been done for decades. The tests that I use to determine if a clutch is a good refill candidate: Is it a stock Toyota type clutch, if after market junk it. Does it turn smoothly with little play, if not the bearing is junk, junk it. Is the thermostat spring rusted out, if so junk it. Is it leaking, if so junk it.

Most Toyota clutches pass, on the majority that I have seen the fluid has given out, warn out. On these clutches, refilling with new fluid will restore like new preformance, or better than new if refilled with thicker fluid.

A thread on the Mini forum that maybe easier to understand;

http://forum.ih8mud.com/79-95-toyota...h-service.html

[Cj80cruiser]

Thanks everyone. I atleast have a starting point with a good idea of what to do now and potential problems to look for.