Well I finally got the thermal switch that controls the fan. #13 on the before mentioned parts fiche. The first test passed with flying colors. I let the bike run for an hour at an above normal idling rpm and did not experience an over temp light once. The fan worked perfectly. True torture test in a week and a half, when she's back out on the trail. I'll let you all know.

 

it still almost sounds like there is air in the system, my bronco was doing the same thing until i made sure all the air was out, it would keep steaming and bubbling out into the overflow.......i'd get that checked too while your at it, it might be staying cool now when your putting around, but come a good ride where your pushing it you'll find out the fast and hard way, better to be safe then sorry

 

To find out if coolant system has a air lock and needs to be "bleed/burped" ,let motor run and warm up ,if top rad hose is hard and hot and bottom rad hose is soft and cool,than you have a air lock and the system needs to be bleed.

Happen to me. Had to fill rad while ATV is running and at the same time shaking the atv to burp out the air. Then the ATV was fine with both the top and bottom hoses being hard and hot.

 

I burped it after I got it back from the engine rebuild and did get out quite a bit of air by doing exactly the same thing while it was running, but doing it again is definitely a good idea. Thanks for the tip on the rad hoses.

 

Was able to get the old girl back on the trail yesterday and the overheating issue is fixed. Along with the Thermal Switch and burping the cooling system, all was good. She purred like a kitten. Thanks to all for your much appreciated advise.

 

Good to hear. A Dealer would of fixed you up for $500. LOL , Happy trails.

 

so if it air locked that will stop the fan from comeing on?and was it the thermo switch in the rad you replaced? im haveing the same problem.

 

After everything I did on my 2000 and after two rides, when I thought it was fixed, it started again. I had replaced fan, thermal unit, cap, flushed, the whole nine yards. Done fighting with it so I through the fan on a toggle switch and run it the entire time, unless going through deep water. It has not overheated since. I was using my winch for hours straight with it idling and no problem what so ever. TOGGLE SWITCH IT!!!!!!!!!!!