Fan clutch or solenoid?

Discussion in 'Ask An Owner Operator' started by Keepforgettingmypassword, Jan 20, 2022.

  1. Keepforgettingmypassword

    Keepforgettingmypassword Heavy Load Member

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    The fan was stuck on. Between what ive read here and google ive test different things.

    Prognosis: fan won't stop running.

    Diagnosis: solenoid has air coming in but not out.

    Maintenance: remove part beat the heck out of it spray it with air hose. Repeat about 5 or 6 times.

    Results: what I'm assuming to be rust dust every where. Even in my coffee. No noticeable physical difference.

    Final step: replace same solenoid on truck. Prior to testing, see if fan spins freely. With restance it does.

    Final test. The fan all but stops spinning, I can hold it still with no restance. Or risk of Injury at this engine tempature. And air is now coming freely from the solenoid. For the first time in a week the truck has idled it self up too running temp.

    Question: that very little sticking that is still happening. How do I isolate it.?
    I don't want to play part darts. But would like it to be back to normal.
    Current temp is almost 180 degrees on dash needle. And the fan is still walking
     
    Last edited: Jan 20, 2022
    Reason for edit: Clarity
    77fib77 Thanks this.
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  3. 77fib77

    77fib77 Road Train Member

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    You changed selenoid. Does air come out of it? If yes it's not just selenoid. If no air hits the fan clutch, it's supposed to engage. Free spin is normal.
     
  4. Keepforgettingmypassword

    Keepforgettingmypassword Heavy Load Member

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    I just cleaned out the solenoid. I didn't change it. But it's working now and the code is gone.
    I don't feel air coming out. But I will soap and water it tommrow with daylight.
     
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  5. 77fib77

    77fib77 Road Train Member

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    If the fan is supposed to be off. The selenoid should send air to the fan hub.

    Selenoid is like $50? You will burn that much in fuel in a day and half, with the fan running. The fan clutch they are $350 to a $1000 and hard to change.
     
  6. Keepforgettingmypassword

    Keepforgettingmypassword Heavy Load Member

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  7. God prefers Diesels

    God prefers Diesels Road Train Member

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    FYI just in case...if you have your A/C or your defrost running, it will trigger the fan without warning. Not sure if you already knew that, but I don't want you chopping your finger off. Makes it hard to type up posts on TTR.
     
  8. God prefers Diesels

    God prefers Diesels Road Train Member

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    Just to dig in a little deeper, the high pressure side of your air conditioning lines hits a certain pressure, and it triggers the fan to draw air across the condenser to lower the pressure. Same thing on defrost. So it doesn't come on "randomly", but you won't know when it's going to!
     
  9. Keepforgettingmypassword

    Keepforgettingmypassword Heavy Load Member

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    That's the knowledge that I seek. Thank you.
     
    God prefers Diesels and 77fib77 Thank this.
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