I have been seeing on this forum where some people have been running a CR8E spark plug as it is suppose to allow the engine to run better in hot climates. Can anyone give me a recommendation for the different ambient temperature ranges a CR6E, CR7E, and CR8E would work best in?

Cat3608
2001 AC 500 Manual w/KN filter

 

Mine came stock with a CR6E. I have changed over to a CR8E since it will be close to 100 soon. A cooler plug should help with gas mileage too. Some guys have made mention that their top speed increased some. A cooler plug will help with elevated cylinder temps on sustained high speed runs. Elevation and carb jetting will have a big factor in what your motor likes or doesn't like as far as plug selection goes. Check it. You want a light brown color on the porceilen. Black=too rich and white=too lean. A hotter plug will help with a rich condition and a cooler plug will help with a lean condition. I say help because a plug will not fix a carb problem. Bottom line is you should be able to run any of those plugs. The 6 plug will help with starts and cold running while the 8 will help with high temps or sustained high RPM's. They are cheap and easy to replace so play with it.

 

Hey, I when I did my 100 mile tune-up I could not find the spark-plug for the life of me. I showed my dad who is a parts saleman for 20 yrs at a chevy dealership and he could not find that damn thing 2. Also how do you check the rear diff. fluid. I opened up the top screw and could see anything, how full should it be. I stuck my finger in the hole and could not feal anything.
Thanks for the help.
Tom

 

For an AC 500, the spark plug is located on the leftside of the engine. Look near where the 2wd/4wd selector handle is and it is located behind the rubber hose you see running horizontally. The plug is inserted down into the cylinder head and is practically impossible to see so feel for the spark plug wire leading to it.

To check the rear differential fluid, remove the small phillips head screw on the lefthand side of the rear differential, then slowly pour gear oil into the large filler hole. When oil starts running out of the phillips screw hole it, then you have the correct level.

 

My rear differential has an 8mm bolt for the drain and the full indicator hole. Remember to drain the differential you have to remove the skid plate back there.

 

Dakotart:

Thanks for your response and Ill check my spark plug for color to determine which plug would probably work the best. I did notice a nice increase in power on the top end after installing a new KN filter and using a CR7E on my 2nd trip out since I purchased it. I normally ride around 8,000-10,000 foot elevations in the mountains and any extra air flow has to help to offset the altitude.

Thanks again!

 

Minehunter:

Your right it is an 8mm bolt instead of the phillips screwhead. I forgot the phillips screwhead was on my old Kawasaki four-wheeler, but I dont know why I would be doing that as this AC500 puts it to shame and is everything and more I ever wanted in a 4x4 ATV.

Good Riding !!!