Engine/Transmission (1998.5 - 2002) Why won't my fan kick on?

[1FSTDSL]

I noticed my truck was running hot when pulling hills and I never heard the fan turn on. So I put a new fan clutch on and I still can't get it to come on. What else would keep the fan from engaging? Did I just happen to have two bad clutches?

 

[John - K5AWO]

We are in good company, my fan clutch doesn't work either. I checked with NAPA and AutoZone, both told me they don't carry one for the CTD. I would have sworn someone just a couple weeks ago said they bought one from AutoZone.



Anyone ever just drill a hole thru the clutch and plug it with a screw? At least I could get some a/c working that way.

 

[JBlock]

I thought mine did come on either, it takes about 210-220 degrees F for it to kick end, I thought the transmission was going out the first time I heard it. Like people say it roars like airplane.

 

[NWhitney]

Autozone

I think you might remember that I said that I could not get one at autozone. I had just to opposite problem with my fan... it would never unlock. It sounded like there was a small airplane under the hood. I found one at the Dealer for $163. I did find on at a junk yard but they wanted $150 and that was for the clutch and the fan. Someone else might know were to get a better deal but that is all I was able to find.

 

[DavidC]

We are in good company, my fan clutch doesn't work either. I checked with NAPA and AutoZone, both told me they don't carry one for the CTD. I would have sworn someone just a couple weeks ago said they bought one from AutoZone.



Anyone ever just drill a hole thru the clutch and plug it with a screw? At least I could get some a/c working that way.

John

Check here

http://www.partsamerica.com





They show one for a 99 and it is thru Checker Auto Parts. I do not know if there is a difference between the years.



Dave

 

[mhenon]

Fan operation

I really thought something was wrong with my fan. It didn't engage for about a year after purchase. Finally hit a steep grade pulling a 10k lb TT. The outside air temps were close to 100 also. Man... . scared the crap out of me. It only stayed engaged for about a minute at the top of the grade.

Since then... I've only heard it once or twice... always with a heavy load on a hot day. With an empty rig. . I doubt you would ever get it to engage.



Mike

 

[John - K5AWO]

John

Check here

http://www.partsamerica.com



They show one for a 99 and it is thru Checker Auto Parts. I do not know if there is a difference between the years.



Dave

Tnx Dave for the lead. It appears there are at a minimum two after market suppliers. I will pursue this until I verify they part numbers are accurate. I note a discrepancy on the shipping weight for the Imperial brand unit.

 

[1FSTDSL]

So at what temperature does it engage? I pulled some long grades with a 12,000lb trailer with the temp. approaching 240, and the thing that saved me was the hill ended. In the summer I am ok if the hill is not too long and traffic does not slow, otherwise my temperature is way too high.

 

[FourBarR]

have you checked the thermostat yet ? could not be opening all the way. take it out put it in a pan of water and heat it up . if you have a thermometer,you can check the temperature that it opens all the way. hope this helps.

 

[NWhitney]

99 Clutch does NOT work on 01

When I replaced my fan clutch everyone could get a 99 clutch but they are only good on 98,99,00. 01,02 is a diff clutch. This is what the dealer told me, both parts and service.

 

[klaybus]

Fan

Last summer I thought I was having the same problem with my fan not engaging. I believe the Service Manual said "The ambient temperature around the fan itself needs to be like 195 deg F" for the fan to engage.

I took a heavy blanket & draped it over the radiator & ran the engine at like 1500 RPM's for 5-10 minutes & the fan ROARED. I should note that the water temp was a touch over 190, probably closer to 195. The procedure is in the DC service manual. I'm working from what little bit of a memory I have left.



Clay

 

[Huff N Puff]

All you guys with over heating problems before you condem the fan clutch,make sure the inside of the radiator is not coated with the slim from the blowby bottle. This slim will coat the inside of the radiator, then road debris will stick to this sticky slim. The fan clutch can't activate because the heat can't get to it,because there is no air flow,no air flow no heat to activate the clutch. The heat stays in the coolant. The only way to clean out the slim is to pull the radiator face it FAN SIDE UP, soak it with engine gunk,and pressure wash it. You cannot clean it out anyother way. Please do your self a favour and look closley on the inside of the radiator with a flashlight especially,if you have not removed the blowby bottle,and extended the blowby hose away from the inside of the radiator. This little tip will keep you from ruining your engine,and will improve the A\C performance. Please do not run a bolt thru the clutch,It would take 40hp to drive that fan locked solid. Merv

 

[klaybus]

Overheating

All you guys with over heating problems before you condem the fan clutch,make sure the inside of the radiator is not coated with the slim from the blowby bottle.



I had a simular problem... . Debris on the radiator. My problem was solved by just blowing off the radiator with 1\4" tubing on a blow gun hooked to compressed air.

Once I blew the debris off all was good. I had already relocated my blow by hose.



Clay

 

[John - K5AWO]

My truck doesn't have a blowby bottle on it. The hose just runs down below the steering sector and to free air. I am going to change that, lots of dirt collecting on the bottom of the engine and frame.



Okay... . before the bolts goes in the clutch, I will have the radiator removed, rodded and cleaned. I need to do that anyway as there isn't any other good way to see into the tubes. I bought it used back in December with 87k on it then.



Oh, and this particular truck is NOT overheating. Temp guage stays on 195 until the outside air gets up over 110* F. that tells me air will flow thru the radiator when the vehicle is moving.



Its just at speeds below 30 mph that I burn up, a/c vents blow 80+ air then.

 

[dpetre]

Mine was over heating 240 degress. I sprayed both sides of the radiator with degreaser and washed it off with hot water. It is back to working again. Buggs, engine blow by, and cotton wood tree fuzz plug up my radiator. Not a problem winter in 3 weeks.

 

[1FSTDSL]

Nobody has really answered my question yet, Is there anything other that the clutch that would keep my fan from kicking on? I have a new t-stat, my radiator is very clean ( moved blowby bottle long ago), replaced fan clutch and I still cannont get this thing to kick on. Any ideas on what else would keep a fan from kicking on above 210 degrees? Thanks

 

[John - K5AWO]

Nobody has really answered my question yet, Is there anything other that the clutch that would keep my fan from kicking on? I have a new t-stat, my radiator is very clean ( moved blowby bottle long ago), replaced fan clutch and I still cannont get this thing to kick on. Any ideas on what else would keep a fan from kicking on above 210 degrees? Thanks

What all of the above have been saying is: The thermostatic clutch will not engage unless the ambient air flowing over it is above 170-195 degrees F.



If the radiator fins are coated with an insulating material (slim, I think its' been called), or dust, or bits of bugs, grasshoppers and the like, that prevents the coolant's latent heat from being transferred to another medium (air) via the copper fins on the radiator.



The fins must be clean or heat transfer will not take place. Do the blanket test mentioned above, that will cause the underhood temperatures to rise enough to make the clutch engage. If the clutch does engage with that test, then you need to degrease the radiator fins and wash it all down.



There is a second reason the clutch may not engage. The thermostat may be opening too soon (lower temp than 195) or it might be just stuck open. Either way, the water will be running cooler than what is needed to cause the fan clutch to engage.



Your question first stated: "So I put a new fan clutch on and I still can't get it to come on. What else would keep the fan from engaging? Did I just happen to have two bad clutches?"



If you have done all the tests/procedures mentioned in this and previous messages, then you have a bad clutch drive.



Hopefully this helps.

 

[1FSTDSL]

Thanks, that does answer my question.

 

[JamesSimpson]

I just breesed through this thread and I was wondering why not just pur in an electric fan and loose the propeller?

 

[1FSTDSL]

I just breesed through this thread and I was wondering why not just pur in an electric fan and loose the propeller?

I was thinking of that, but I heard they do not move as much air.