Clutch fan

[JAsaro]

(11-11-2020 )Coronado126 Wrote:  On big trucks, air is used to release the fan clutch and turn it off.

If your air pressure goes below 100 psi your fan clutch is supposed to "fail on" and lock so the engine can't overheat.

I'm losing some of the context of the problem from your post, but from I understand what you're saying, you don't have a fan problem per se, you have an air pressure problem somewhere else on the truck and you're noticing the fan staying on because it's the loudest part.

Now, if your fan kicks on like normal when your engine starts warming up, and then after it's cooled down your fan doesn't unlock and you start losing air pressure when your engine coolant temp has returned to a normal range, then yes, I'd suspect your fan solenoid is sticking and leaking air.

thanks it does work correctly in the morning when I start the truck up the fan engages and then eventually shuts off and then while I’m driving down the road it’s fine I cannot hear any air leaking anywhere