What is the proper procedure for installing a flywheel back on the crankshaft of my scrambler 500? I am aware that there is a specific torque requirement listed in the manual. The greatest hurdle is how to keep the crankshaft from rotating. Is there a solid method of limiting rotation outside of purchasing a special tool?

If it comes down to it, where would I obtain such a tool?

Bye the way. OPT was right on when he suggested that my backfiring , spitting back , etc stemmed from a bad camshaft on my 2000 scrambler 500 ho. The exhaust lobe was 2mm beyond the wear limits. I really appreciate his expertise.

Many thanks,

Ron

 

If you're really dead set or proper torque setting on the flywheel you will need this tool. https://polaris.spx.com/Detail.aspx?id=180&cat=1&sub=24
The manual shows torque to be between 58-72 foot pounds. If you walk into most shops and catch a mechanic replacing one chances are you'll see him just "zap" the nut down with an impact wrench! I don't even think I had this tool in my "necessary" tools on the wall(may have,but never used it). Same thing on the front clutch,most guys just impact them on. Both sides of the crank shaft ends are a tapered snug fit,the only difference is the keyed timing slot for the flywheel side. Even a small amount of force on the flywheel nut and you'd have to have the puller to remove the flywheel again! The main thing is don't crank down on the impact enough to break the shaft! Couple of 2 to 3 second impacts and it ain't going no where After a few years you kinda get a feeling for it. On all the other torque settings on the engine,then yes,go by the book!

 

speaking of flyweels, how do you remove one? im guessing there is a special puller. im trying to salvage what i can from the other 400 engine that exploded

 

I kinda thought that an impact wrench would work, just wanted to get some feedback to make sure that I didn't screw something up...seems like sometimes I break more things trying to fix them up than I get fixed up
Thanks for the input... Polaris is real proud of their tools...
Ron

 

Just a cheap steering wheel puller or a harmonic balancer puller if you want a heavier duty one. Along with (three) 3 inch or so 8 mm bolts for the flywheel.

 

Yes,they are proud of their tools! Be careful if you have a 1/2" impact! Hit it quick and let off! A 3/8" impact is plenty sufficient to zap the nut also.