2004 polaris sportsman 500 overheating

bjohn10 · #1 (**permalink**) 01-08-2012, 01:03 PM

I recently purchased a used 2004 Sportsman 500 HO with 1,700 miles. The machine mechanically sounds solid however, when I run the machine for 15 to 20 minutes at a time, antifreeze in the overflow pushes out. The fan turns on and runs pretty much the entire time. When I first purchased the machine, I noticed the fluid level in the overflow was low. I opened the radiator cap and the fluid was right at the top. I filled the overflow to the middle of min/max. I rode the machine for the first time afterward and as discribed above, the fluid pushed out the overflow cap. No overheating light or any indicator on the machine comes on. Any help would greatly be appreciated. Also, the radiator is clean front and back with no leaks. No leaks in the hoses either.

fl1tontj · #2 (**permalink**) 01-08-2012, 03:49 PM

I'm dealing with the same prob, let me know ifyou come up with anything. I even took the t stat out and it still runs hot.

**Bruce!** · #3 (**permalink**) 01-08-2012, 05:14 PM

Welcome to the board!

Russ C · #4 (**permalink**) 01-09-2012, 04:26 AM

remove radiator cap, let machine run till fan comes on , will burrp air out of system , if its pushing fluid out of radiator may have blown head gasket

4getful2 · #5 (**permalink**) 01-09-2012, 07:05 AM

Take the radiator cap and have it tested.

bjohn10 · #6 (**permalink**) 01-09-2012, 05:13 PM

Thanks very much for the feedback. I will test the cap, made replace it if, and run the machine until the fan kicks in. Hopefully this solves the issue. It does not smoke or smell of antifreeze other than the residual from it pushing out the top of the overflow. I will test it this weekend and post the results.

smokeybone · #7 (**permalink**) 01-11-2012, 04:20 AM

Keep me posted..my 03 600 just did the same thing yesterday!!! Hell, I'm not even sure my radiator has a cap.

bjohn10 · #8 (**permalink**) 01-11-2012, 07:05 AM

I will keep you posted. The bad thing about a early 2004 Sportsman is they hid the raditator cap under the front storage rack without an access door in the front plastic. I have to remove both just to turn the cap off.

smokeybone · #9 (**permalink**) 01-11-2012, 07:30 AM

Thanks for the info! I guess I do have a cap! lol I'm thinking mine is the thermostat, but my fans are not comming on??

bjohn10 · #10 (**permalink**) 01-14-2012, 05:26 PM

Well, it turned out to be a bad radiator cap.... The spring would move up and down but the rubber gasket on the bottom was shot. I replace the cap and ran the machine for two hours on local trails near my home with zero issues. The fluid would fill the overflow to the max line, then the fan would kick on and the level would drop. Thanks to everyone for the assistance and for responding. I truely appreciate the feedback...

Brad-