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drifterpilot's avatar
drifterpilot
Explorer
Jul 01, 2013

Transmission Cooler Fans

Two months ago I replaced one of my transmission cooler "pusher" fans with a new S-Type fan ordered from online. The cooler is mounted directly in front of my engine radiator. Right out of the box, I applied 12 volts to the bare wires and it ran fine. Since it has been installed I have driven the coach a couple of thousand miles (Florida - Virginia 80-90 deg. temps) at highway speeds (with no mountain climbing). I have pulled over in Rest Areas in an attempt to see/hear the fans running with no luck. In the past I have observed and heard these fans run. I believe there is a thermostat that controls power to the fans, but I do not know where it might be or how to get it allow 12 volt power to pass.
Comments please.
Class A

5 Replies

  • drifterpilot's avatar
    drifterpilot
    Explorer
    Jul 01, 2013
    Update...
    I heard from my son-in-law (mechanic). He advised me to idle the engine with the dash air on High Speed. I did this and within 15 minutes I observed both pusher air fans kicking in. My situation query resolved.
    Thanks to all for your comments.
  • rgatijnet1's avatar
    rgatijnet1
    Explorer III
    Jul 01, 2013
    On my GM 8.1L engine I used the same connector that was used on my old fans, when I replaced them. I just cut the wires and spliced in the wires from the old fans. I believe the temperature sensor is within the engine control module that sends the signal to the fans to come on. I used two of the Flex-a-lite Model 392 S-type fans for my replacement and they cycle on and off whenever the temps start to rise.
  • drifterpilot's avatar
    drifterpilot
    Explorer
    Jul 01, 2013
    rgatijnet1
    No, I didn't use the same 12v connector that attached to the old fan as it would not have power to it (without the temp sensor energized). I used a portable batt jumper pak to energize the new fan. I checked the two 30 amp Auxiliary Fan fuses on the External Fuse Block, both good. Prior to install, I also checked the fan to be in the "pusher" mode.
  • Sully2's avatar
    Sully2
    Explorer
    Jul 01, 2013
    Rewire it to a switch...toggle or rocker...mounted in the coach ( dash area) so you can turn it ON when you wish and OFF when you wish.

    LG gauge wire and fused
  • rgatijnet1's avatar
    rgatijnet1
    Explorer III
    Jul 01, 2013
    I assume that you used the same power cables that sent electric to the old fan. Did you insure that the fan was set up in the proper "pusher" mode before you installed it. In most cases, the fan blade needs to be removed and flipped to be used as a pusher instead of a puller. Then you have to insure that the polarity of the wires is properly observed.
    I would check that the fuse is good to supply the power(usually a large fuse of 15+ AMPS) and then you may want to insure that the temperature sensor is functioning properly.

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