Stihl 034 with bent crankshaft?

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Stevo Bambino

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I bought a used Stihl 034 off craigslist. The jug and piston looked good from what I could see through the exhaust and spark plug hole. everything seemed to be in great shape. It ran, though it was very smokey. I figured it just need some carb work. The jug had been off as evidenced by the orange rtv silicone gasket. When I asked, the guy said he put this saw together with parts from two other saws, both of which had problems. I dissembled and cleaned the carb out. I brought it to my dad's cabin to cut up some downed trees. I began by letting it warm up and adjusting the jets properly. When I started cutting it seemed to be getting hotter than it should so I turned it off. I could not get it to start again. Looking in the spark plug hole, piston and cylinder still looked good. Brought it home to do a pressure/vacuum test. It would not hold any pressure at all. Flywheel side crank seal was original and not even touching the crankshaft. Bearings still felt great. I replaced the flywheel side seal, the clutch side looked new. It did not pass pressure test, clutch side seal is also leaking. Then I realised that as I turned the crankshaft, the bubbles rotated with the crank. I checked the crankshaft for wobble by placing my scrench on the table next to the potruding crankshaft so that the screwdriver part was going strait up alongside the end of the crankshaft. I then rotated the crankshaft and it has a .020 wobble. It has a similar wobble on the flywheel side, though not as bad. My guess is the original owner tried getting the flywheel off by hammering on the crankshaft and bent it. What would you recommend?
1) replace crankshaft with used Stihl crankshaft off ebay and hope the used crankshaft is good?
2) replace crankshaft with aftermarket crankshaft and hope it is of adequate quality?
3) buy used bottom end off ebay and hope it has a good crankshaft and bearings and no stripped out screw holes?
4) replace the clutch side seal and just run it?
5) any other ideas are welcome.
BTW, I do not have a crankcase splitting tool.
Thank You.
 
Buy a used crank, as in the trading post. Enough of them out there.

Don’t need a splitter. Just tap the alignment pins out towards the fly side, then get the 5 case bolts out. Heat entire case up in oven or on grill to 350, them wearing heavy welding gloves, grab it and tap the crank out of both side with a mallet or brass/nylon hammer. The bearings will come out attached to the crank, but the crank is getting tossed anyway.
 
best to remove crank as it could be crank end bearings causing the out of round(cage broke and all bearings are on one side of bearing causing issue) this would also could cause over heating issue too
 
With the bikes assembling with out tools the crank would taper the porkchops opposite the rod journal after assembly. Even with some saws we ran into this. I took a chisel opposite the rod journal and tap the porkchops till the chops are parallel and the crank spins freely. Then make sure the crank is centered.
 
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