Snowmobile Repair: Ski Doo track plastic drive gear drum replacement, axle bearings, wd 40

Question
After being told not to add Sta-bil to the gas for storage on my snowmobile, I was told rather to start it once a month and run it with the track up until it completely warm up, then shut it off.  I did this every month until yesterday. When I started it up, the track was completely bound up and would not move.  I have been told that the bearing in the main track drive are melted and seized up due to what the dealer suggested. (no cooling of the bearings)  How do I go about replacing these bearings myself as I cannot afford to take it to a shop.  The sled has only 780 miles on it and has cost me about $300.00 everytime I take it out.  It is a 1999 Ski-doo Grand Touring 583cc. Does everything have to come out through the bottom or the top?  I would greately appreciate some instruction.  Thanks

Answer
Hello Dale,

  Sta-bil is the way to go, I have never had a problem with it. Now as far as the track not turning, The bearings might have just set up and could still be useable. Try spraying alot of WD-40 all over where each of the are located ( look under the track, you can see them, they are at the ends of the axle. Try sharply giving the track pulls with your hands, back and forth. There is a good possibility that it will jump loose. If it doesn't, Try loosening the track as far as it will go, and then turning the drive axle by hand, to be sure it's bearings are the problem. If it's the bearings, here is how to get the job done. It's not a bad job, just takes a bit of time. I don't blame you for not taking it to the stealer, that gets expensive after awhile. The entire track and frame does not need to be drop for this job, if you are only replacing the drive axle bearings. You do need to take the chain case/transmission cover off, and to do so, the sled will either need to be turned on it's side, or, you will have to drain all of the oil out of it, so there isn't a huge mess of oil when you take the case apart. When you have the case off, there are two sprockets inside. Remove the bolts that hold them in place, and the remove the entire chain and sprockets together. You might need to loosen the chain tensioner bolt quite a bit to get them off. Your sled has more gears then a normal sled, so try to take your time, here is a file for reference:  http://216.37.204.202/Skidoo_OEM/Skidoo.asp?Type=13&A=339&B=21    .   When the sprockets are off, there is a round plate that has three bolts on it, and nuts on the other side. Take the plate off, and the bearing will be exposed. Now, look on the other side of the sled, and you will see that after removing the speedometer flange  (   http://216.37.204.202/Skidoo_OEM/Skidoo.asp?Type=13&A=339&B=26   )   there is the same three bolt plate. Take this plate off, also. Now that the plates are off, you can wiggle and maneuver the shaft out, and get the bearings off of it. You may need a bearing puller if they are on tight. Re-installation is the reverse of removal, except you will need new chain case gaskets and seals to avoid a leak. Don't forget to tension your chain, and add new oil when finished. I hope this helps for a ball park, if you run into trouble in any specific area, contact me and I'll be more than happy to help out! Best of luck to you with the sled! --Arcticatman