Hi All,

So I just bought a 2000 TRX350TM Fourtrax. It would appear that the original owner made it so that the oil cooler fan can be turned on via an aftermarket switch he installed on the display.

When the switch is turned on the oil temp light comes on immediately even if the engine has only been running for a minute.

As far as I can tell the oil temp sensor is behaving normally it does whats its supposed on start up and the turns off. I haven't had the chance to run the machine long or hard enough to see if it or the fan comes on automatically once the oil reaches the necessary temperature.

So I'm just wondering if I need to worry about having the fan running all the time or only to turn it on if the light comes on. I also wonder what reason they would have made it so you can turn the fan on manually?

Just wondering if anyone has encountered this or something similar or had any thoughts.

 

Possibly your machine is a victim of Honda's little joke. For late 300 and all 350s they wired the fan through the CDI. Sometimes a faulty CDI would put the fan on all the time. As CDIs cost an arm and a leg, the easy way was accept the fan running all the time, or wire a switch in so you can turn it off yourself. Kawasaki Bayous, had a fan with a manual switch anyway, so this is no big deal. If you are going slow and pulling, chain harrows for example, stick the fan on. If you are leaving the bike idling for 30 min (why do people do that?) Stick the fan on. Very hot weather? Stick the fan on.

 

Thanks Merryman,

thats what I assumed. Any idea why the high oil temp light would come on when the fan is switched on?

 

I rather think there is only one temperature sender switch in the sump, so both fan and temp warning must be wired together in some way.