I had a stator problem back in July and put a new one on. Well it ran great for about a month, but now there is a big hesitation when giving throttle. It will idle all day long, but if you give it half throttle and hold it there, it will rev up a little, then back off to idle, rev back up, then back to idle. It will do this cycle as long as you keep it at half throttle. Full throttle and it wants to die (sounds like choking out). I replaced the coil because during troubleshooting I broke the cap, so it has a new coil and plug, and stator from last time. Any ideas? I took off the carb and cleaned it but it didn't seem really dirty. And I bypassed the inline filter just to be sure it was getting gas. It will barely pull up a hill and gives small backfires periodically. I'm stumped!

Thanks for any help!

 

Did you pull the plug? If yes, what does it look like? Get it running again with the 1/2 throttle issue and then pull plug & post pic...that'll tell us if you're in a lean or rich condition...or if normal...

 

I know you said you replaced the stator,but wouldn't hurt to check specs. Found some aftermarket stators that didn't last too long before having problems. At least this can eliminate the stator as having anything to do with the problem. The main stator black wire to the white/red should be around 450 ohms resistance. Black to black/red,800 ohms,black to yellow/red 0.5,black to white 0.6. Plus black shouldn't short to ground.

 

Thanks OPT. As far as the plug goes it looks OK. The stator results are:

B-BR = 570

B-YR = 525 (should be 800)

B-W = 12

B-YR = 10

B-GROUND doesn't short.

Do you think the B-YR is too low? I'm concerned about the aftermarket now, it was misterelectrical and there were a bunch sold!

 

Check your leads against each other,will show some resistance that you can deduct. Check again as you have listing wrong. Black to white/red around 450 ohms, black to black/red 800 ohms. Black to yellow/red 0.5 ohms.Black to white 0.6 ohms.Values given have a +/- 20% range.

 

I see I typed them in wrong. Yes the B-BR is 525 (not YR) and B-WR is 570. I plan on removing the stator today and see if its dirty etc. My son was riding in the rain/mud a few days before it started acting up!

 

Just pulled the flywheel and everything is pretty clean in there. Could that low reading of 525 Ohms vs the spec 800 be the problem? I swear it sounds like its not getting a steady gas flow, or the gas is bad (misses and backfires). I'm wondering now if I should drain the gas, plug off the oiler, and premix some high test fuel just to be sure. Any thoughts?

 

Try the easy stuff first like you mentioned. Fresh gas,fresh plug,clean air filter,verify carb is clean and fuel is flowing good.VClean the fuel valve bowl and screen that people over look also.Plus you can pull the oil tube from the carb and see if the end is oily. If so,the oil pump should be ok. These oil pumps for the most part are reliable. I didn't have any oil pumps fail on any of the Polaris youth models from 2001 until I left late 2010. They don't need high test gas or race fuel as we learned years ago. They won't run worth a crap on it. 87/89 is fine. If all of that's eliminated then the low stator readings could be suspect as the problem.

 

Thanks OPT. Ok so I drained the gas and removed the carb and cleaned it again. I'm not sure about the fuel screen you mentioned in last post so please let me know where to find it as I think there is a fuel flow problem. I put it back together and it fired up after some priming but same issue. Misses and hesitation/backfires. So I put it to half throttle and let it die. I pulled the plug and it was very dry. And lots of carbon as you can see from the attached pics. This is a brand new plug.

 

No fuel bowl or screen to clean out on this fuel valve. Plug carboned up either from too much fuel or could be a stator related problem.I'd recheck the carb float level and if fresh fuel and a new plug doesn't solve the missing/hesitation then it could be a stator breaking down.Plus you mentioned riding in the rain/mud before it started acting up could have something to do with it. The stator cover slots just lets in gobs of water that can screw stators up.I've changed a bunch of these over the years because of water.Plus your readings especially on the black/red wire are not with in the 20% +/- allowed in the manual.