Crankshaft/oil seal removal, the slide hammer trick
Check out the video for a quick and easy way to remove crank seals, shift shaft seals, and any other external oil seal from an engine or transmission case. Using this slide hammer seal removal method will save time and money from having to split the cases to drive the seal out from the interior side of the engine or transmission case. The tools you will need are simple (listed below). That is really all there is to it! (This slide hammer technique only works on seals that install externally) See pictures below. This works on 2 stroke motorcycles.
Small center punch
Variable speed electric/battery drill
Small drill bit(s) suitable for the size of seal
2 lb Slide hammer with sheet metal screw pulling attachment
Appropriate sized sheet metal screw
click images for a larger view