my 2000 polaris expedition 425 is overheating and the fan will not kick on. Has anybody experience this or is it time to go to the shop.

 

I have a bud that had some trouble with overheating while he plowed snow. That's the only time. However, he put on a manuall switch to overide the fan. It will turn on automatically OR manually. He also said that Summit Performance (hot rod shop in Akron Ohio) has a new switch for the fan. Is yours overheating at low engine speeds? Maybe the water pump isn't circulating good enough.

 

my 96 sp500 has been doing this . when 1996. still does it. at low speeds and overflow on max not spilling out.it feels hot. DAN 96 SP500

 

It may be your thermal switch that turns the fan on at a certain temperature. Some riders in here have had problems with it. HTH

98 Scrambler 500
00 Trailblazer 250

 

I have read on this forum that some y2k polaris's got defective thermal switches. I believe dealers are aware of this, and should provide a replacement.
Brian

 

If the temp light comes on & the fan is not running, it is either the temp sensor, or thermal switch for the fan. I suppose the fan could be bad, but I never heard of one. Double check to be sure it isn't low on coolant. Some seems to disappear during the first few hours of use (air pockets, I suppose) and that could be confusing the sensor).

 

I have a 2000 500 sportsman and it also was overheating. If you have your shop manual it will tell you how to check the thermo cencor. you will also want to check the amp voltage draw of the cooling fan. mine was drawing to much and needed replacing.

 

Farmerlarry,
It is easy to figure out if the fan or sensor is bad. If you look on the right side of the radiator shroud at the top there is a black plug with two wires in it. Unplug this connector and make a jumper wire with two male spades and plug it in. Turn the key on and if the fan comes on then the sensor is bad. Not an uncommon thing on 2000 model bikes. My sensor has been replaced twice. The fans do go bad also but mainly if you ride in deep water or deep mud.

 

my fan is working fine.

 

I had the exact opposite problem, not overheating but fan running constantly. It is a known problem with Polaris, one dealer here in Columbus, claimed to know nothing, I called another dealer and they said, bring it in, we've replaced a bunch of them. It's the oil temp sending unit from the oil cooler. Transistor, I think the manual refers to it.