Thanks OldPolarisTech.

I havery started dismantling. Yesterday during the twenty minute test, the fan never came on. I am going to voltage test the fan while I have it apart. Maybe it's the sensor thing too, but first thin is first, check the impeller.

 

OK, so pulled the impeller housing, very clean in there, the gasket was kind of falling apart, so I put it together as carefully as I could. I should probably replace that gasket. Impeller was in perfect shape, nut was nice and tight.

Anyways, less than 1/2 cup of coolant fell out...is it likely that I am just completely out of coolant? Would make any engine overheat!! I am going to fill it up, I have a call in to my shop to see how much coolant it should take...

 

I'd replace the gasket,hard to really keep one from leaking. If the impeller is tight,not damaged,then it's down to a possible sticking thermostat(rare to happen) or the radiator is trash. Plus you may have to remove it and thoroughly flush it and also make sure the back of it is clean around the fan area.Plus again the plastic filler neck could cause problems along with the radiator cap. Before you pull the radiator I'd do pressure test on the cooling system. Should hold 10psi with no drop. Plus are you sure there was no wet area around the weep hole on the water pump cover? Another way that you could be low on coolant is from a leaking w/p seal.

 

Just wanted to update this thread....

It must have been when I let it run 20 minutes and the coolant was bubbling from the radiator, must have been an air bubble. Once I pulled the impeller housing and nothing came out, I refilled the radiator with it running, rocking the unit to help "burp" it.

Yesterday I was pulling big rocks for a rock wall, very hard on the ATV. When not idling and winching, you are hauling rocks via rope up a slope. She never over heated, the fan ran a lot, and the coolant jug stayed right where it needed to be. The impeller housing was very hot after a while, and so were the hoses. I might be all set! I still should redo that dang gasket...

Thanks for the help!

 

Yep change that gasket or be prepared for leaks.. If you think burping a Sportsman is hard you ought to try a Ranger 500/700/800 with radiator hoses about 6 feet long or so.. We had to jack those up sideways to be able to work all the air pockets out..At least the 800 had a thermostat housing with a bleed screw built into it that made it a tad easier but still took awhile