I use the "brute force and ignorance" method of removing prop-drivers from tapered shafts.

This consists of placing the engine on a hard wooden surface (backplate end down) then placing a small block of aluminum atop the threaded end of the crankshaft and giving this a good smack with a hammer.

Okay, you can stop cringing -- it really doesn't hurt anything.

if nothing comes loose after a couple of good blows I put a heat source (usually a propane torch) on the prop-driver (NOT the crankshaft itself) until it just sizzles if you wipe it with a wet finger -- then try again.

If it still won't budge, try a little more heat -- but don't melt it. On a real stubborn driver you can wipe a little plain laundry soap (the yellow bar stuff) on the driver and heat it until that soap just starts to discolor (it'll start turning brown) -- but no hotter!

This method has *never* failed to release a crankshaft/driver and I've never damaged either in the process.

Points to watch:

1. Don't use this method unless your reason for dismantling the engine is to *replace* the bearings -- because it may cause some brinnelling of the balls in some engines.

2. Make sure you hit the aluminum block/crankshaft squarely with your hammer blows -- this is to ensure you don't bend the threaded portion of the shaft (I have never bent one yet).

3. Don't substitute steel for the aluminum block -- its purpose is to protect the crankshaft's threads from being damaged

4. Make certain that the wooden surface you're sitting the motor on allows the rear face of the crankcase to contact evenly. Some motors won't sit flat on a large flat surface because the diameter of the cylinder is too big. In such cases, move the engine to the edge of the table or whatever so the larger diameter bit can overhang, allowing the crankcase rear to sit flat.

Yes, I know this sounds brutal and a great way to wreck your engine but, if you understand what you're doing and take care, you can get even the most stubborn prop driver off this way without any trauma.

The big benefit of this method is that it doesn't leave ugly scars on your prop-driver.

As tested on: Thunder Tiger 46Pro and SuperTiger G90 engines :-)