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RE: Fan clutch? - Chamberpains - 06-23-2020

If its a Keyser fan hub, the clutch disc is removable and fully serviceable. I solved mine sticking every humid morning by removing it. Lightly sanding the embedded flakes of steel off the pad and reinstalling it. I haven't had a problem for well over a year now. And it just sat for 2 weeks without running it and it still didn't freeze up.


RE: Fan clutch? - JimT - 06-23-2020

Not sure which one it is. Never had this problem before, but I sprayed down the inside of the engine bay as the sun was setting and things were still pretty damp under the hood the next morning. Probably won't repeat that scenario again.


RE: Fan clutch? - SquareOne - 06-24-2020

My hub will typically do the same during very rainy days (like we're having now) or if I wash down the engine bay and it happens to sit till the next morning. Just a couple pops on top the hub and it's never let me down as of now.


RE: Fan clutch? - Lonestar10 - 06-24-2020

What I've been doing since I had this issue in the Lonestar is anytime I spray out the radiator or get things wet is I bring the engine up to 1500-1600 and turn fan on off a few times that way any moisture in the clutches gets scrubbed by the clutches grabbing at that rpm


RE: Fan clutch? - JimT - 06-25-2020

(06-24-2020 )Lonestar10 Wrote:  What I've been doing since I had this issue in the Lonestar is anytime I spray out the radiator or get things wet is I bring the engine up to 1500-1600 and turn fan on off a few times that way any moisture in the clutches gets scrubbed by the clutches grabbing at that rpm

I like that idea. Probably why I've never had it happen when visiting one of those Truck Wash places while the engine is warm and then you drive away.

I don't have a manual switch to control my fan, but I've been thinking about adding one. Any suggestions on how to do it? Splice in a wire at the air solenoid? Or is there a better place?


RE: Fan clutch? - Lonestar10 - 06-25-2020

you can splice a wire into the fan solenoid but i beleive the truck will throw a code every time you use it im not sure if its ECM or BCM that needs to be reprogrammed or tapped into to do it perfectly.

the solenoid always has + the BCM/ECM grounds it to turn on the fan so you would run a 2nd ground wire to it.


another way to get around this would be install a second solenoid after the trucks OEM one and you can choose how to wire this one either constant + or constant ground with the switch engaging the opposite. this way the ECM wouldnt know the fan is being turned on and the ECM/BCM solenoid would continue to work as normal for fan engagement.

only problem with installing another solenoid or installing a controllable ground without going through the ECM/BCM is that the fan clutch will not shut off at certain rpms that can cause the fan to self destruct if you accidently over spin the engine.


RE: Fan clutch? - Rawze - 06-25-2020

(06-25-2020 )Lonestar10 Wrote:  you can splice a wire into the fan solenoid but i beleive the truck will throw a code every time you use it im not sure if its ECM or BCM that needs to be reprogrammed or tapped into to do it perfectly.

It is an ecm code. it is easy enough to shut off the error inside a custom tuned or de-mandate program if someone wants it not to show.


RE: Fan clutch? - JimT - 06-26-2020

(06-25-2020 )Lonestar10 Wrote:  you can splice a wire into the fan solenoid but i beleive the truck will throw a code every time you use it im not sure if its ECM or BCM that needs to be reprogrammed or tapped into to do it perfectly.

the solenoid always has + the BCM/ECM grounds it to turn on the fan so you would run a 2nd ground wire to it.


another way to get around this would be install a second solenoid after the trucks OEM one and you can choose how to wire this one either constant + or constant ground with the switch engaging the opposite. this way the ECM wouldnt know the fan is being turned on and the ECM/BCM solenoid would continue to work as normal for fan engagement.

only problem with installing another solenoid or installing a controllable ground without going through the ECM/BCM is that the fan clutch will not shut off at certain rpms that can cause the fan to self destruct if you accidently over spin the engine.

All great points, thank you. My main purpose would be for use while parked to bring the temp down a bit before shutting the engine off. But you gotta think about edge cases and if I sell the truck what would someone else do with it.

As for blocking or shutting off the error seems less elegant. Plus, it would make it more difficult should an actual error occur at some point in the future.


RE: Fan clutch? - Chamberpains - 06-26-2020

[attachment=6762]
This is what the back of a Keyser fan hub looks like. Those 6 small screws can come out and the clutch disc can be removed and serviced. Also when the disc gets worn, the new plates have nipples on them so they can be flipped and you can get more service life out of the clutch. This can all be done with the hub fully mounted on the truck and belts in place. They are simple to service.

Now Horton hubs are a whole other animal. My new to me truck has 1 and I learned the rebuild kit for them is close to $600, a remand hub is $750 and a full on new 1 is $1250. But they come as a whole assembly. Fan hub spindle, hub and clutch assembly as 1. I elected for the remand hub. $150 wasn't worth me finding something seriously wrong or flawed and still having to go buy a replacement. This is what the Horton fan hub looks like.
[attachment=6763]