I have a 1995 LT 250 4wd that I have had since new. Strictly for hunting. It is a go anywhere tank. Since new it has had a tendency to carbon foul pugs. Worse in hot weather as it gets real hot running slow, working on stands, food plots etc. Historically I have just changed the plug & oil when it gets to running really rough. I use D7 or D8 EA plugs. Any idea what could be done to help this problem? Great machine & I am just trying to make it last.

I appreciate your help!

 

May need to rejet carb,sounds like its running rich.Also lugging the engine during work or chores will cause them to load up and foul a plug.If its like my kingquad it ran rich from the getgo.never have to choke it no matter how cold it is.

 

Would an iridium plug help this? I do have to choke it in cold weather. Hate to screw around with the plug as other than fouling plugs it has been absolutely reliable since day one.

 

Havent tried one of those plugs myself,so i wouldnt know.

 

I had the exact same problem with my 91 250 2wd. A D7EA just would not last. So i swapped to a D6EA and leaned out the fuel in the carb. (NGK gets hotter with the lower number) I have the pilot screw about 1/2-3/4 a turn out instead of the recommended 2 turns. The jet needle clip on mine is at the 2nd from leanest position. drove it over 5 miles yesterday for the first time with a lot of low speed crawling. Never had a single problem with it dying or anything. Checked the spark plug and for the first time since I've owned the quad it was not completely covered in carbon.

Have not tried the iridium as around $10 per plug i believe. If you run one please let me know how they work. I have ran a champion powersports plus plug you can get from your local walmart and had better luck with them on a rich running engine. Might try it with this leaner set up and see how i like it.

 

had this issue when we first got our kingquad. switched plugs to one of those dual-head sprark plugs, but didnt see any gain from it. now we just run the champion equivalent of the ngk it came with, and it works great, no more fouling.