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99 600 always overheating

11K views 7 replies 5 participants last post by  grizzgreen600 
#1 · (Edited)
hey guys ive been having a lot of trouble with my grizzly overheating. i bought it used so i dont know if its always done this bu as long as ive had it, it does. when i first got it the thing would overheat within about 10 mins of riding. i attributed this to the horribly beat up oil cooler. so just a couple days ago i bought a uhaul oil cooler which is actually bugger and has more surface area than the stock oil cooler. it has worked better and delayed the overheating light by only coming on when i am crawling fairly slow through the brush. havent had any problems in open areas at a decent pace. is there anything i can do to fix this slow crawl overheating issue? my cooler is brand new and very clean so thats not the issue. i hooked up the fan to the headlights and keep it on all the time so im still not sure why its overheating. i guess its possible im running ean but my plug is black which indicates im rich. but the plug could also be fouled i guess. im just not sure. any ideas? oh and btw i have read quite a few threads on overheating and cooling issues but all are on 66- and 700's which have the liquid cooled systems. im working with an air cooled system here so none of the current threads have helped too much.
 
#2 ·
had a thought....is it possible for an exhaust leak to cause overheating? i found a nut missing from an exhaust stud on the head and i can wiggle the pipe around where it connects to the other pipe going down the side of the body. not sure if its really leaking bu its possible.
 
#3 ·
and had another thought lol. been reading about exhaust wrap. is it possible that wrapping my exhaust at the head will cut down on some overheating as well by keeping heat out from behind the oil cooler?
 
#4 ·
I bought a used 98 in August and after a couple rides I started looking around and confirmed that they all run HOT....like burn your legs hot.

I also swapped out the stock cooler (damaged) for an automotive transmission cooler...likely the same thing you've got.

If there's room (and there is lots on mine) I'd add a 2nd one.

The one I have has a lot more surface area, but isn't nearly as thick as the factory cooler, so all told, it likely had a little less cooling surface than the stock one I took out.

If your fan is running, I wouldn't say an exhaust leak would be a factor at all, as far as it leaking on or near the cooler....
 
#5 ·
well i wrapped every fuel line i could find and also wrapped up the bottom of my gas tank with some reflective heat tape accompanied by a layer of heat resistant welders blanket. took the grizz out for a ride today through some thick mud and water and didnt overheat once. so it did good. but i will look into a second cooler cause you just never can have too much cooling lol.
 
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