Hey everybody I'm new here and a newbie to atv's I just bought a 1987 350 4trax foreman and can't get it to run consistantly.I have had it runnining a couple of times and when it does it runs great however it floods and gets gas in the oil which I have heard is a prob with those paticular models,also I don't have a manual and don't know what spark plug to use,the one that is in it is a champion and has been fouled.Any help would be greatly appreciated

 

I've never seen much problem with getting gas in the oil. If the float valve was leaking, It should be leaking gas out the port on the bottem of the carb. Unless the overflow tube in the floatbowl is clogged. If the float valve was leaking, it would drain your tank overnight, or most likely drip on the ground. The two problems I saw with that carb (besides contamination from sitting of course) are the needle wearing a hole in the needle jet too big, causing plug fouling, rich running, the hotter they got the worse they ran. The fix is to replace the needle jet set, from Honda it comes as a kit with needle, needle jet, clip and retainer. Don't go putting those crap aftermarket carb kits in either. I've never seen one come with a needle jet anyway. The other problem I recall carb wise was with the linkeage between the butterfly and the slide. It's found underneath the plasic cover on the side of the carb. There is an adjustment tang, so that those two items can be synched. Sometimes they can be vastly out of adjustment. Or the tang breaks (that part doesn't come separately from the carb either). causes it to run rich and flat at low speeds especially. The NGK standard heat range for that machine is eight. I've used d8ea and think that is standard, but have also used dr8esl and even dpr8ea9 (a projected tip plug) before. I run d7ea which is one range hotter in the colder months, but if your machine runs really rich you may want to use it all the time.

 

The worn needle and needle jet could be the problem because when I get it running it runs very rich and dosn't want to idle no matter how you ajust the idle mix screw and the hotter it gets the worse it idles plus this machine has seen a lot of use and was setting behind a barn unused for a year or so.(lots of missing parts etc).I cleaned the carb but will double check the overflow tube to make sure its not blocked.Thanks for the plug info.