Fan clutch help

[mitch4712]

Ok so I was driving home from work and and i decided to finally use tha A/C.
About 10 min after I turn it on (while drive down the highway) I notice the temp gauge starts to climb so I turn the A/C off and it goes back to normal.
Now that I think back I could never hear the cooling fan working. my last truck was 97 ram 1500 and you could hear the fan engage. i have never heard it on my B3000. I popped the hood this morning and spun the fan by hand and it free spins about a half of a turn before stopping.

My question is should I hear the fan running? when should I be listening? how can i do more testing to see if its faulty?

thanks for yalls help.

 

[RonD]

If engine is cold from sitting overnight the fan fluid will be thick so on start up you should hear the fan "biting" the air.
After about 30 second or so the fan noise should get less as the fluid becomes thinner, if you shut off the engine at this time fan should spin easily, at least 1 or 2 full revolutions depend on how hard you spin it.

The Fan clutch is warmed up by the rad temp not engine temp, on it's front is a bi-metal spring that engages the fan blade as it warms up.
Once rad has warmed up, shut off engine, fan should not spin easily, it will always move, there is no direct drive, but it shouldn't "spin" just move with your hand.

Radiator shroud is what makes fan clutch work, if that is removed then fan clutch never gets warm enough to fully engage.

I think you are on the right track about the fan clutch and the symptom you described.


Another test which makes a mess is to warm up the engine/rad then use a rolled up newspaper with engine idling to try and stop the fan, if you can then clutch is bad

 

[mitch4712]

Ok thanks RonD. ill give it a shot.

 

[bucko]

If its anything like the fan clutch on my 2000 Ranger with a 3.0, it will roar! Three weeks ago I had mine changed while it was in for a new A/C compressor and dryer. They said the clutch fan was getting weak, so I had them change it. On the drive home, I thought they installed freakin' bus engine!

When it's cold, you should feel resistance when turning the blades (engine off of course!). In an early morning first startup, you should definately "know" it's spinning at idle. At highway speeds, the fan will slip, as plenty of air will flow through the A/C condensor/radiator. I suspect with your A/C running, the additional heat within the A/C's condensor was added to the heat of the water within the radiator, and not enough cool air was flowing to cool down the radiator. The clutch fan slipping was of no help to you, so you saw the temperature rose.

Needless to say, three days ago I removed the clutch fan setup and went the route of an e-fan setup.

 

[mitch4712]

I checked out the fan clutch. With the engine warm and at idle I can use a rolled up news paper and stop the fan. I guess I'm gonna be changing it. I also found a small leak in the radiator. Guess I'm gonna be changing it too.

 

[RonD]

Yes, good idea for both

 

[bucko]

I checked out the fan clutch. With the engine warm and at idle I can use a rolled up news paper and stop the fan. I guess I'm gonna be changing it. I also found a small leak in the radiator. Guess I'm gonna be changing it too.

Depending on the engine, year, and age (mileage), it can be fun removing that clutch fan. On my 2000 3.0 V6, facing the engine from the front of the truck, the clutch fan nut turns clockwise to remove it. I tried removing the belt, then holding the waterpump pulley with a belt wrench, that was a no go. I ended up taking it to the shop that installed the new one three weeks ago to have them loosen it for me (gave the mechanic 20 bucks; about the price of the special "tool" used to hold the waterpump pulley). It took him over a half hour to break it loose. I guess he did not know his own strength when he installed it!

 

[mitch4712]

I found the space between the radiator and the AC condenser was about half full of junk.
Clutch fan still not working and the radiator stil needs changed but it doesn't get hot with the ac on anymore.

 

[bucko]

I found the space between the radiator and the AC condenser was about half full of junk.
Clutch fan still not working and the radiator stil needs changed but it doesn't get hot with the ac on anymore.

Good observation. I will occasionally clean the front of the radiator with a soft toothbrush, to remove borken leaves, bubs, etc from its fins to help in air flow. Any bent fins are carefully bent straight as well. Be careful doing that, as you don't want to break them from the tubes, rendering them useless in removing heat.