I have a 2000 Polaris Scrambler 400 4x4 that seems to have an issue with the four-wheel-drive system. The part that stumps me is that it is only one wheel! The right side (while sitting on it, looking forward) works just fine, however, the left works only part of the time. I have gotten the coil replaced, and the issue continues, I've swapped the pigtail leads (thinking one side may be getting less power than the other) and the same side has issues. The battery seems good, the right side works, I'm not sure what would cause the left to only work a fraction of the time. And now, because of this, the u-joint snapped because whenever the four-wheel-drive is on, it cuts in and out and seems to put a lot of stress on the components. Please help...

 

Try a better ground on the coil ground wires to a stronger common ground and see if that solves it like in the video.On a 500 but same system. IF it doesn't help,then you may have a coil sleeve and inner pole out of adjustment that can cause an erratic pull on the armature plate,damage to the face of the coil sleeve or inner pole, or the plate itself could be warped if you haven't changed it out.Plus a simple thing like wrong torque on the hub nut could affect engagement. 10-12 foot pounds max.

 

I've yet to try that, but as I stated, one side has always worked fine, so wouldn't swapping the leads cause the other side to have issues? I could try it, but I don't believe it will do anything because the same side is having issues even while plugged into the side that has always worked.

 

If the problem was entirely electrical then swapping leads would indeed affect the other side. Since it's a mechanical system also,that's where the problem is. I have to kind of retract that a little. First off check the resistance on the gray and brown wires on the coil on the offending side. If it's around 24-27 ohms,then the coil is ok and you can eliminate the coil. That would then lead to a mechanical problem. Seal sleeve face worn or pushed in,inner strut pole damage so the armature plate couldn't get a good pull from the coil,damaged or warped armature plate,wrong torque on hub nut,dirty or wrong fluid used.

 

 

Sounds mechanical to me then.Resistance values are usually 10% +/- of specs.