[rooftop1201]

My over heat light comes on but don't think it getting hot... had this problem a few months ago but rebuilt the top end seemed to help but now it doing it again any ideas would help don't no if it needs rebuilt or if I just have something dumb with it I can't figure out

 

[Steve86trx250R]

Have you flushed the radiator? Also how does it run? A lean engine will overheat could possibly even be a water pump issue. My 250r was getting hot quick and running lean all due to a cdi problem but it was so lean you couldn't ride it the spark plug test should tell if it's lean could even be an air leak somewhere those are all the obvious things I would check

 

[rooftop1201]

The bike run great act's like nothing wrong ill try to flush the radiator see what that does thanks

 

[rooftop1201]

How bout a normal running. Anyone no what it should be

 

[Steve86trx250R]

Another thing would be to check the cylinder temp with an infared temp gun

 

[rooftop1201]

I did that the light came on and the gauge was bouncing around from 160-180 witchh seems about normal I think....I read owners manual said light may come if low on oil but the oil eye sight showed I had plenty of oil...would a cracked head gaskit cause it to give a false reading to the censor?

 

[Here 2 help]

Try changing the temp sending unit.

 

[Steve86trx250R]

If you had a blown head gasket you would be loosing coolant whether it is burning it or leaking into the cylinder or blowing it out you could do a leakdown test on it to check that it could be the sensor like the other person said if that is suspect and you know somebody with a 450 I'd try there sensor before buying a new one no reason to buy it if you aren't sure that will fix it

 

[rooftop1201]

Going to try the temperature sending unit will let u no thanks

 

[rooftop1201]

OK well I flushed radiator started bike it over heated fan didn't kick on this time..I unplugged icm box plugged back in seems to be running fine thanks for all the help...BTW temp. Sending unit was fine

 

[mud99]

Welcome to the forums. Is the vents in the radiator blocked were it cant get a good flow of cool air