Hi, new to forums.. I know this is a Monsoon (Yerf Dog) atv, but from what I understand it is virtually the same as the polaris in the early 2000's.. I've tried the chinese forums but I think a lot of those are 4 strokes and I know when I google monsoon, polaris comes up a lot. So with that said..

this atv however is challenging my patience.

I picked it up for $5, not running. It is actually a clean, solid quad. It obviously wouldn't start, so I checked the compression. Low. Put new rings and piston in, cleaned up the cylinder some. 115 psi HOT and COLD now!

Still wouldn't start, found left crank seal displaced. Put new one it.

It fired up immediately! It ran like a solid two stoke.. for 5 minutes. At that point, it starts to lose it's idle, get kinda blah blah ish, then boom.. it's out. I can restart, but not for long. Let it sit for 5 minutes and the whole cycle repeats.

Plug color actually looks perfect. Electric choke seems to be working. I cleaned and inspected the card 100x, it actually looks good. Like I said earlier, the compression is 115 hot and cold, the spark looks great. No air leaks from what I can see.. the carb boot looks great, all cylinder bolts torqued.

Again, when cold/warm it carbs like it is fuel injected! Strong clean running atv.. but after 4-6 minutes.. the idle starts to get sloppy then it just bogs out and dies.

The stator ohmage is a little off, but not too bad.. the coal ohmage is a little off as well.

If I manually choke the carb (by plugging the intake OR covering the left venturi hole on the carb opening, it springs back to life for 30 secs or so.

Please advise! A chinese dealer in OH seems to think my stator is bad.. but I would think choking it to bring it back to life would indicate something else?

Worn reeds? They actually look pretty good and clean. Right crank seal bad? Bad stator? Help!!

Oh, and thanks

 

Sounds like you have most of it covered,but just from my experience the most trouble I had on the little ones was with the stators,but you say you can get it up and running again by blocking the carb intake? I'd check for a pinched vent line from the fuel tank(could be vapor locking) or partially stopped up fuel valve or kinked line.Plus if you just replaced the one crank seal,might be a good time to replace the other one behind the stator,plus if it's like most 50-90 stators I've worked on there will be a lot of dirt inside the flywheel and stator area that would need to be cleaned. Try these first and see how it does. OPT