I have a 2000 xplorer 400 that I use to plow snow from my driveway. Yesterday while attempting to plow the snow around my stuck sister-in-law, I heard a loud bang and now my xplorer goes no more. It has been back firing some when I press the power button for backing up but this bang was much louder. I think that I blew the engine but looking for some advice before I haul it in to be fixed. I should have left the sister-in-law stuck in the snow bank.

 

it could be as simple as the timing getting off and making it backfire or it could have busted a piston or you could have thrown a rod (very unlikly unless it was knocking before) i would check compression first then take the carb and exhuast off and look into the holes. slowly run the piston up and down and see if there is any skirts missing. while your poking around look under the motor and see if theres any metal chunks

 

Thanks. Wasn't so bad after all.

I took the quad to the Polaris repair shop and after explaining the problem, the mechanic started talking about rebuilding the top end for @$1800 which is about the value of the quad. Then I explained the "big bang" and he started talking about rebuilding the entire motor which would be ~$3500 or so. I was shocked. So I left the quad there and told them to spend about an hour diagnosing the problem and to get back with me. Much to my surprise, about 3 hours later the shop called me back and to my dismay, the only thing wrong with it was the spark plug has blown out. The threads were still fine so it must have loosened over time and finally backed all the way out. Certainly explains some of the backfiring. Well, I replaced the drive chain and they put in a new spark plug so I'm back on the road again.

 

I`ve heard that kind of a BIG BANG!!!!!! noise before.[img]i/expressions/face-icon-small-blush.gif[/img][img]i/expressions/face-icon-small-happy.gif[/img]