on our 83 fc, 3208 cat, the rad fan is always on now after redoing the
radiator and replacing the belts. looks like there is a sensor on the
front of the motor, which goes to a relay, also goes to the overide
switch below steering wheel. any ideas ?? thanks, pete
If your fan control is like ours it will engage if there is not power (Failsafe?) If I turn the ignition on when the 3208 is cold thereis power on the air valve that controls the fan.. The engine does not need to be running. I am assuming that yours has a air clutch and not an electric clutch. When I got our 82 I had to replace the wiring as it was so old and deteriorated that the fan operation was erratic.
- Chuck Wheeler-
1982 FC 31SB Fort Worth TX
on our 83 fc, 3208 cat, the rad fan is always on now after redoing the
radiator and replacing the belts. looks like there is a sensor on the
front of the motor, which goes to a relay, also goes to the overide
switch below steering wheel. any ideas ?? thanks, pete
Pete - The Horton air clutch is a retrofit. Originally the sensor
turned on an electric clutch directly. Now the sensor turns on the
electric-to-air relay which turns on the Horton air clutch by way of
the relay.
If the clutch is constantly getting air (staying on) then the relay may
be constantly getting power, or the relay could have gone south.
To test the relay, disconnect the wire(s) from one side of the relay
and see if the fan engages. If the fan engages, then the relay is bad.
If the fan does not engage then the problem is electrical. The power
could get to the relay from the sensor or from the bypass switch.
Disconnect the wires from the sensor and the bypass switch one at a
time to determine where the power is coming from. When you learn how
power is getting to the relay, look for the reason: Bad bypass switch
and wiring, or bad sensor and wiring.
Its a process of elimination. Best of luck.
Bob Griesel '84 FC31 WLII WA
--- In
WanderlodgeForum@yahoogroups.com, "racetrash"
wrote:
>
> on our 83 fc, 3208 cat, the rad fan is always on now after redoing
the
> radiator and replacing the belts. looks like there is a sensor on the
> front of the motor, which goes to a relay, also goes to the overide
> switch below steering wheel. any ideas ?? thanks, pete
>
You may want to check the heat sending unit on the front of the engine
block.
Harold Prescott
'85 FC35
Quartzsite
--- In
WanderlodgeForum@yahoogroups.com, "racetrash"
wrote:
>
> on our 83 fc, 3208 cat, the rad fan is always on now after redoing the
> radiator and replacing the belts. looks like there is a sensor on the
> front of the motor, which goes to a relay, also goes to the overide
> switch below steering wheel. any ideas ?? thanks, pete
>