Oil cooler fan

   / Oil cooler fan #1  
F

Frank Sorbello

Gold Member
Joined
Jul 12, 2011
Messages
362
Tractor
Power Trac PT-422
I am now in the process of trying to get the oil cooler fan to work. I don't have a diagram of the wiring for the PT-422. Does anyone know where the relay to the oil cooler fan is? I have to broken coming off the fan to a toggle switch, from the toggle switch I am not sure where they go.

Thanks

Frank
 
   / Oil cooler fan #2  
Sounds like you don't have the stock configuration, since they don't have a toggle switch to turn teh fan on/off.

On most of the PTs, the fan is wired to a temp sensor that is mounted on the inlet to the oil cooler up underneath the hood of teh engine compartment, and the wiring from there runs to the ignition switch. The fan only runs when the oil hits 120F or something like that. On cold days, it might not come on at all.

There is no relay for the fan.
 
   / Oil cooler fan #3  
On mine the temp sensor went bad several years ago. I now have a spade connector that I hook up directly to 12V before I start the tractor. Eventually I will wire it to a switch, rather than replacing the temp sensor, since so many people report failure of that part.
 
   / Oil cooler fan
  • Thread Starter
#4  
My PT-422 has a toggle switch mounted on the engine cover. There are two wires coming off the switch that have been disconnected. I did find the the oil tmp sensor. Not exactly sure how to check if it is bad or not. It is connected. It has an inline fuse attached. I think it might be better to use the toggle switch when running. Do you know how to wire the fan direct?

Thanks
Frank
 
   / Oil cooler fan #5  
Find the wires coming off the fan. One should go to ground somewhere. The other should go to a switch, then to a fuse, then to +12V. You can either connect to +12V right off the battery or as in my case with the Kohler engine, there was a +12V lead coming off the engine. Better to go to a relay that is energized by the key switch, so you can't accidentally leave the fan on.
 
   / Oil cooler fan #6  
So was running the PT today for the first time in warm weather (~80F) and after an hour or so the fan hadn't come on at all and I started to get a little surging like bad gas. Not sure if it overheated, but it definitely doesn't run as smooth at idle and has some oil in the carb and is not starting as easily. Going to check the valves and see how that goes. Running at 1/4 throttle feels the same as always.

Anyway, fan had a bad temp switch. All I did was run a jumper wire from one side of the switch to the other and the fan runs perfect. Turns out the positive lead from the battery to the temp switch is wired for ignition-on only, so if the PT is running, so is the fan. Two minute fix. Now I just gotta hope the lack of a fan today didn't do any damage.
 
   / Oil cooler fan #7  
So was running the PT today for the first time in warm weather (~80F) and after an hour or so the fan hadn't come on at all and I started to get a little surging like bad gas. Not sure if it overheated, but it definitely doesn't run as smooth at idle and has some oil in the carb and is not starting as easily. Going to check the valves and see how that goes. Running at 1/4 throttle feels the same as always.

Anyway, fan had a bad temp switch. All I did was run a jumper wire from one side of the switch to the other and the fan runs perfect. Turns out the positive lead from the battery to the temp switch is wired for ignition-on only, so if the PT is running, so is the fan. Two minute fix. Now I just gotta hope the lack of a fan today didn't do any damage.
 
   / Oil cooler fan #8  
Injuredoften said:
...I started to get a little surging like bad gas. Not sure if it overheated...Now I just gotta hope the lack of a fan today didn't do any damage.
Click to expand...

No worries.

I would bet $$$ that you were starting to experience vapor-lock in the fuel pump. The close proximity of the fuel pump to the exhaust can cause all sorts of bad behavior, and the extra heat under the hood without the fan probably put your engine over the edge.
 
Last edited:
   / Oil cooler fan #9  
I doubt you did any damage without the fan running. My fan has to be hooked up to +12 manually and sometimes I forget for hours and hours. Probably not good in the long run. But once in a while probably did nothing to be worried about. Rest easy. :)
 
You must log in or register to reply here.
 

Footer Links 1

Top