Bottom end???? help and advice needed

Well all the guys told me to get my motor fixed. How hard is it to take apart a bottom end and rebuild it? I have always been real mechanical but I guess it is all the gears and transmission that intimidate me. Top ends are no problem and are a breeze. But the guy that does all my motor work broke his collar bone and cannot do it till he heals up. What special tools would I need besides a torque wrench? Any help or advice is appreciated. I got the factory and a clymers (spell check) manual, hopefully I can get this together and get back to roosting it up.

Ive watched someone tear apart a old tri-z 3 wheeler motor and it didn't look to be extremely difficult. Make sure all the gears come out together, photo document it, look at all the parts schematics and how tos you can find. You will need a case splitter to break open the cases correctly NOT a screwdriver. I think TT member defaultpeanut had a good guide on the bottom end with lots of pics.

The clymers should tell you about all the screws and locations of them. Tap on the output shaft and crank end, and it should start to come out. Watch for shims or spacers on the ends of shafts. When you go back together, make sure the tranny shifts easily and that all shafts spin freely. Go thru each gear shifting and watching for change in output turns. If one side goes up sideways, stop and back it off and square it up. I know it is intimidating the first time, but its not difficult. Just make sure you go back together clean. Prep is the key for no leaks. I use brake cleaner on all mating surfaces.

Never, ever, tap on the crank. It is pressed together and you can very easily knock it out of true. Not a big deal if you are replacing or having the crank rebuilt but, I would still never do it. Get a case slpitter.

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