I started a little project the other day breaking down an old lawn mower engine (Briggs & Stratton) just to see how it ticks and with the intention of putting it back together again. I cannot get the bottom half of the crank case away from the crank shaft because of the big bulbous end where the mower blade bolted into. In order to free the crank shaft, it needs to slide through a rather small opening in that half of the case, and the big fat end won't go. I know this piece can come off, otherwise the engine could never be rebuilt. It looks like it was pressed on, and there may even be a key way. Anybody know how to remove this piece off the crank? Thanks for any help you can provide.
