I think my fan clutch is gone bad, whats the easiest way to diagnose it.

 

ssually when they go bad , they lock up solid. You will not be able to turn it by hand, except with also turning the water pump pulley too. The good part, it doesn t really hurt anything. Mines been locked up for years, probably hurts milaege like .002 .

In some cases the hub assembly can come apart, which causes the fan to wobble etc...that can do damage if not fixed.

I ve been wanting to try 4 electric fans....

 

Sort of doubt that, a locked up fan pulls 23 hp.

The way to check is the fan should spin by hand but stop when you aren't pushing. It also could be your temp has never gotten hot enough for the fan to lock up, I'm lucky if mine locks even once a year.
Do you just think it's not working or are you overheating?

 

If a locked up fan isn t moving how does it use 23 hp? 23 hp, I don t doubt somewhere, but probably way way less at cruising rpm 2000 or less.

Thats why I d like to go electric....

 

If your fan won't turn by hand with resistance with the engine off, or if you run it real hard in hot weather (towing, etc.) and the temps get too hot without hearing it come on, then it is bad. And yes, they use a lot of power if they are locked solid because they are pulling a lot more air. I know people have put electric fan clutches in (like semis use) to get more hp and better fuel economy. If a fan clutch bearing comes apart and sticks engaged it could be out of balance and is a good way to ruin a water pump bearing by continuing to drive it that way.

 

it has a real hard time warming up in the cold weather, fan seems to run strong even at idle at 0 degrees, did a flush and fill didn't help, truck runs 180 on the highway, actually the needle sets almost even with the 1 on 190, but stop for 5 minutes at idle and it cools way off, checked the lines in and out of heater core, they warm right up both of them so i don't feel thats a issue, wan't to change the thermostat as a precaution but with those long bolts holding the alternator bracket, I'm afraid they'll snap off, and I don't have a garage.

guy at auto parts store says if the resistince is the same when you pull the fan over from cold to hot (180) then the thing is stuck, but he has to special order and i've gotta keep it so I wanted to be sure, it does have the same resistance bye his method of checking so I'll have to get it.

 

Sounds to me like you're trying to beat a dead horse, nothing is wrong.

Cummins says,

THE COOLING SYSTEM USED ON THE CUMMINS DIESEL ENGINE EQUIPPED VEHICLES PROVIDES THE CAPACITY AND PROTECTION OF THE HIGHER GVWR AND GCWR RATINGS AVAILABLE ON THESE VEHICLES. OWNERS SHOULD BE ADVISED OF THE NORMAL SLOWER WARM UP AND LOWER ENGINE OPERATING TEMPERATURES ASSOCIATED WITH DIESEL ENGINES.

THE COOLANT TEMPERATURE GAUGE WILL FLUCTUATE ON DIESEL ENGINE EQUIPPED VEHICLES. IT IS INFLUENCED BY VEHICLE LOAD, OUTSIDE AMBIENT TEMPERATURE AND EXTENDED IDLE TIME. THIS FUNCTION IS CONSIDERED NORMAL

 

I've owned since new in 98, actually i ORDERED IT, never seemed this bad before, on throwing heat, used mostly in the winter for pulling the snowsleds, actuallt last summer i could here the fan cycle on and of when i'd leave the house, I'll see how it reacts when the weather changes and go from there, thanks for you're imput, may be time for some maintenance on some things, trucks been awful good to me.

 

Now that you've given us more info is sounds like indeed the fan clutch needs to be replaced

Most likely any auto parts can get you one, no need to replace the fan blades, just the center. I paid about $65 at Napa a few years ago.

 

If I were you I would replace the fan clutch if even think it might be bad. I went through 2 radiators an d 2 fans then finely repaced all of it the last time. Now I just wish I would have done it the first time so I could have used the money else wear.

Good Luck,
Joey

 

Guys, on this temp issue my 95 will go from the 180 down to the low end of temp and back the entire time driving. Just up and down. It has done this since I bought it and I just thought that was normal. Do I have a problem I should look into?
Thanks,
Rena

 

Renacolt-

My temp has done the same thing since it was new in terms of temp fluctuation.

 

One more time
Cummins says,

THE COOLING SYSTEM USED ON THE CUMMINS DIESEL ENGINE EQUIPPED VEHICLES PROVIDES THE CAPACITY AND PROTECTION OF THE HIGHER GVWR AND GCWR RATINGS AVAILABLE ON THESE VEHICLES. OWNERS SHOULD BE ADVISED OF THE NORMAL SLOWER WARM UP AND LOWER ENGINE OPERATING TEMPERATURES ASSOCIATED WITH DIESEL ENGINES.

THE COOLANT TEMPERATURE GAUGE WILL FLUCTUATE ON DIESEL ENGINE EQUIPPED VEHICLES. IT IS INFLUENCED BY VEHICLE LOAD, OUTSIDE AMBIENT TEMPERATURE AND EXTENDED IDLE TIME. THIS FUNCTION IS CONSIDERED NORMAL