[28sstony]

Long story short, at the end of last season I picked up a 99 136" Zrt with a 900 tripple motor with unknown miles. One cylinder had slightly less compression than the other two so I bought it with a top end refresh in mind. I pulled appart the top end a few days ago and half the studs and other fasteners were siezed and or stripped upon removal. All the pistons and rings were completely worn out, even the wrist pins were grooved and discolored. Upon further inspection the rod/crank bearings had worn and cracked needle cages. I decided to take out the motor and completley dissasemble it, which still hasnt happend becase one of the motor mounts has a rounded out allen/plowhead bolt preventing the crank case from being split. Anyway, when I flipped over the engine to remove the lower crank case bolts the first thing I saw was a ton of epoxy smeared on the very center of the bottom side of the case. I can only assume this was done to cover a split or cracked case....


Should I even consider trying to rebuild this thing, or start shopping for a lower mile replacement engine?

 

[Empire087]

Id just look for a new motor, odds are your gonna need a new one anyways.

 

[jesse500]

new motor...

 

[bj.hardy]

Long story short, at the end of last season I picked up a 99 136" Zrt with a 900 tripple motor with unknown miles. One cylinder had slightly less compression than the other two so I bought it with a top end refresh in mind. I pulled appart the top end a few days ago and half the studs and other fasteners were siezed and or stripped upon removal. All the pistons and rings were completely worn out, even the wrist pins were grooved and discolored. Upon further inspection the rod/crank bearings had worn and cracked needle cages. I decided to take out the motor and completley dissasemble it, which still hasnt happend becase one of the motor mounts has a rounded out allen/plowhead bolt preventing the crank case from being split. Anyway, when I flipped over the engine to remove the lower crank case bolts the first thing I saw was a ton of epoxy smeared on the very center of the bottom side of the case. I can only assume this was done to cover a split or cracked case....


Should I even consider trying to rebuild this thing, or start shopping for a lower mile replacement engine?

split the case to find out,, and im not sure it very well might be cheaper to look for a motor, your talking about a whole new motor by the time you are done, sounds like a bad case of oh shit...

 

[Luke]

Def dont sound good. At the very least you prob have a crank and 3 cylinder cores. All the bolt on stuff is still godd right; carbs, coils, recoil, etc....? Id say try to find a bare bones replacement and go from there. Or at least a good bottom end/case if your jugs are usable. Good luck.

 

[99ZRKittyCat]

It doesn't sound good at all. I rebuilt my 99 ZR 500 motor 2 years ago and used Wiseco Pistons Kit (http://www.wiseco.com/) and new cylinders from Millennium Technologies (http://www.mt-llc.com/) I also had a bad hole in the bottom of the Crankcase and decided to just buy another one. Try to find a used one though because if you order one its extremely expensive and you cant order just the bottom either, only the entire crankcase, also with new bearings on the crank and rods it gets pricey all in all my rebuilt motor cost me $1200. With that much wrong even with cheap parts and being you have a triple that will make it even more expensive. If you find a motor for between 800-1200 you would probably come out ahead.

 

[28sstony]

I finally split the case. I couldnt find any obvious cracks however the center rod journal was severly mangled. Also on the crank, the main bearings have what look like piston rings on them (pardon my terminology, I'm new to two stroke stuff) Anyway one of the main bearings had half a ring wedged in the lower half of the case and there was no upper half anywhere. The crank case had bits of silicone packed in every last part of the case. I have pics, but I'm not sure how to post them.