Crankcase separation being a bitch..

[MexicanGringo]

Hey gents, trying to separate my crankcase, three corners loose, but the corner by the output shaft wont budge.. I think the seal is broken all round so its not sticking, but feels like theres some mechanical obstruction from the gearbox or something?ALL crankcase bolts have removed ... Any advice please!

[vfrman]

Are you SURE all the bolts have been removed. There are a few internal bolts that are hard to spot.

[Neosophist]

Have a look at the microfiches, helps a bundle when doing this

A rubber mallet also helps lots.

DO NOT give into the temptation of using a screwdriver / prybar / chisel et al to try and leaver the cases apart, that works wonders for destroying them.

[MexicanGringo]

Right, if any1 has this same problem, then answer is to raise the free corners as much as possible, then continue tapping the corner opposite the output shaft with a rubber mallet, which lifts the half at an angle and eventually frees it. The problem is caused by the oil seal on the output shaft..

[Neosophist]

It should just slip off the output shaft, was there some dirt or surface rust / corrossion etc on the shaft.

Friend once struggled for hours trying to hammer a crankcase apart off a 50cc ped, I sanded the shaft and it dropped apart :D

He had destroyed the oilseal by then though

[MexicanGringo]

first the crankcase halves were stuck together because of it, then the output shaft was stuck in the upper half, and need a fair bit more tapping to free it!

[MexicanGringo]

and yeah i destroyed it!