the 700 over heats after 5 min of run someone told me the SENSOR-THERMAL/HARNESS but i didnt change anything yet just wanted to see if any one know what the hell is going on

 

If fan doesn't kick on when it overheats,then possibly the thermal sensor located at the bottom of the radiator could be shorted out/faulty(kicks the fan on). You can also check the fan motor directly with with 12 volts if this is the case to see if it works. If fan does come on but still overheats,could be air in the system, or a muddy radiator especially at the back around the fan area, or a faulty radiator cap if spewing out coolant. Hope this helps you get started! OPT

 

Like OPT said main thing to determine is whether or not the fan kicks on. When I had a similiar issue with my 600 it was a combination of both things. The thermal sensor went bad causing the fan to not come on but the radiator was also packed full of mud and debris.

 

is fan working and is the radaitor clean on front and back? just something to check if it's not the sensor

 

thefan comes on and the radiator is clean too

 

Sometimes mud and dirt can get behind the radiator enough to where its best to remove the fan assembly and flush the radiator thoroughly from the front and then from the rear! If the radiator is clean as you say,then remove the radiator cap,run until the fan kicks on,top off coolant in the radiator and overflow bottle and replace cap. This purges any trapped air. Check that coolant is moving in the radiator to eliminate the water pump impeller as a problem. If still over heats and coolant surges into the overflow tank,the radiator cap could be bad (13 psi rated) and you can get at a lot of auto parts stores.Also possible that the temperature sensor on the cylinder could be staring to fail and sending hot message to the light before the fan comes on?(Have had some do this) STILL think its a partially clogged radiator, air pockets,or cap, if the fan is working properly!I've been wrong before though! Keep us updated! OPT

 

i thought i had a fairly clean rad on my 800 too until i really took a close look and ended up taking it completely out and pressure washing the dried mud as it wouldn't come out w/ just a hose. i would say my 800 was about 30% plugged and it was enough to over heat it. the twins run alot hotter then the singles as well.

 

I thought the same with mine always rinsed it good and it appeared clean until I actually removed the radiator. It was almost completely packed full. I had to soak it for a few days to help loosen all the packed mud. I would really inspect closely....

 

My friend thought his SP700 rad was clean, we took the rad out and the hard to see top half of the rad had baked mud in the fins that look like concrete.

A pressure washer with hot water had to be used, no garden hose with the rad in the ATV was going to get it cleaned out.

 

people just don't realize how bad it can be when the mud isn't just dried in there as it is baked.