M1152 fan issue

[Muttmutt]

I have a m1152 that i cant get the fan to stop running, I’ve applied 90 psi to the hose to the fan clutch and it kicks back fine. Ive replace the power steering pump, the beer can, the black module the temp sensor with the good one. I just cant get the 90 psi at the beer can hose. I know the pump is working because I plugged off the relief side and i got the 90 psi and the fan kicked off but with everything hooked up like it should be i only get 20 psi or less. Ive done all the continuity testing and ohms testing and it all comes back good. What am I missing! It also doesn’t help that there’s a giant 400 amp alt in the way. Thanks

 

[Hummer Guy]

I have a m1152 that i cant get the fan to stop running, I’ve applied 90 psi to the hose to the fan clutch and it kicks back fine. Ive replace the power steering pump, the beer can, the black module the temp sensor with the good one. I just cant get the 90 psi at the beer can hose. I know the pump is working because I plugged off the relief side and i got the 90 psi and the fan kicked off but with everything hooked up like it should be i only get 20 psi or less. Ive done all the continuity testing and ohms testing and it all comes back good. What am I missing! It also doesn’t help that there’s a giant 400 amp alt in the way. Thanks

In my opinion, ditch the whole system and go for the viscious fan clutch, best upgrade I ever did, no hydrualics, TDMs, or Cadillac valves to worry about.

You may want to check your Temperature Sensor, TDM, & Cadillac valve, I kept having these go out which made the fan stay on, here's a good video to troubleshoot that: Understanding your HMMWV/Humvee Cooling System | How to Check Your Fan Clutch - YouTube