Overheating? over flow bottle filling up

[hwf-racing]

I have a new Apex MXR-LT 100 with about 3hrs on it. The first couple practices the coolant would fill the overflow bottle about one quarter, this last practice the overflow bottle was full and when I let it cool down it didn't suck it back to the rad. So, I brought it home checked plug still running a little rich, checked impeller, no issues. bleed the coolant system nice stream, Ran the quad for about 15 min but not hard, shot the cyl with the infrared therm showed 165 degrees/ then shot the head 157 degrees:confused: Also checked rad cap! I'm new to these Minis should I be worried or is this normal? Next time i'll bring the infared therm to the practices and not leave it at home!!!

[Nichols Atvs]

its not cooling u have air in the system some where it should not be that hot .period could be something blocked check the impeller make sure its not broken and bleed the system really good i have never had coolent go in to the bottle ever.

[G-force NW]

Check your Radiator Apex has been having issues with bad radiators that have small pin holes in them just sold a customer a steel one yesterday had the same problem. he took off the radiator put in water and ran air through it and said thier were pin holes all over in his new quad also.

[redonkulousruntsracing]

the caps on the radiators leak also, you should file the lip down smooth and be sure its sealing well.

[hwf-racing]

Thanks for the replys, I will apply all your ideas this weekend!!!

[grillbutt]

Nicholls ATV is bang on the button !!

[wrhracing]

Originally posted by hwf-racing
I have a new Apex MXR-LT 100 with about 3hrs on it. The first couple practices the coolant would fill the overflow bottle about one quarter, this last practice the overflow bottle was full and when I let it cool down it didn't suck it back to the rad. So, I brought it home checked plug still running a little rich, checked impeller, no issues. bleed the coolant system nice stream, Ran the quad for about 15 min but not hard, shot the cyl with the infrared therm showed 165 degrees/ then shot the head 157 degrees:confused: Also checked rad cap! I'm new to these Minis should I be worried or is this normal? Next time i'll bring the infared therm to the practices and not leave it at home!!!

If you problems aren't solved by now:

Don't mount the number plate in front of the radiator.
OR
Possibly you now have a blown o-ring on the head pushing compression into the coolant system, pushing the coolant into the bottle. (From one of the previously mentioned possible problems). This usually fills the bottle quickly, less than a lap, sometimes less than 200 feet.
After re reading your post... the cylinder will be hotter closer to the exhaust port.