I just recently bought a 1997 Polaris 400cc sport, It snowed and got about 8 inches of snow here today my four wheeler has been sitting for 2 days without me riding it. I went out and started it and it fired right up and ran for about 10 seconds and died. My starter did not work when I got it so I have to pull start it. Every since It died I cannot get my pull start to pull out of the casing. I assume this means my motor (possibly) locked up??? IF anyone has any other ideas of what it might be I would appreciate it if you would let me know what it could be. It has plenty of gas and plenty of oil in it so if it does need rebuilt how much am I looking at start to finish??? Does anyone have any ideas of where I can get the parts that I will need for cheap. Thanks alot

 

The best thing to do at this point is pull the clutch housing off. You can then grab the primary clutch and try to turn it. Did it act like it locked up when it died or did it just smother out? If it has the original piston and you were gassing it a little when it quit, it might have broke a piston skirt which is all too common on machines with a few years on them. A top end rebuild is not hard to do, and boring and piston will be the biggest cost. If that's the case, there is a guy who sells the original type replacement piston kits on e-bay for about $50. I would spend the little extra and buy a weisco if needed. Hope this helps,Bubba

 

I wouldnt go with the cheap piston.Go Wiesco worth the extra cash.And I am needing a topend on my 400 and I checked with my dealer and its going to copst right at $200 for bore job,piston and gaskets.If I have the extra cah I may get it ported if not I will just polish it and smooth it out. But before I jumped to conclusions like Bubba said check the clutch to see if you can turn the motor over and then before you tear the motor apart take the cover off where the pull rope is to be sure nothing is broke or hun up in here.

 

I have rebuilt my Trail Boss 2 times since Stock. First rebuild I went with Wiseco and it lost compression and wore very quickly had to rebuild in 1 year. Secone time I went with WSM their basically stock pistons, they are cast. I've been running it with a cast piston for 4 years now still has 112PSI. I would go with cast not forged pistons unless you're a racer and need somthing to hold up at high RPM. A Forged piston (wiseco) is very rigid and strong this is good and bad. Good because it will have a less chance of breaking. Bad because it doesn't have the natural ability to hold oil, a cast piston does which makes it wear less. Why do mostly all of the maunfactures that make 2 stroke engines run a cast piston in them stock. Because they last longer