"The bad news is that, if they
"The bad news is that, if they are badly seized, you will have to destroy your propellers to remove them. The good news is that aluminum props are not expensive, especially if you buy them second hand.
First, you will need to split the propeller outer hub in such a way that you can separate it from the rubber hub. You can use a 90 degree angle drill and drill a series of holes in line very close to each other across the length of the outer hub (stop drilling when you reach the rubber hub), then cut through the holes with a chisel or an electric drill until you make a clean groove. Alternatively, you can use an oxyacetylene torch or a zip cutter. You may need to repeat the procedure once or twice until the outer part of the propeller comes apart in two or three pieces. You then will have to figure out a way to remove the rubber hub (cutting it with a blade, drilling, etc) until you only have left the splined inner hub. Again, you will have to either drill a series of holes or use a Dremel electric disc cutter to split the inner hub, and you will have to be very careful not to drill or bend the propeller shaft. I would not recommend applying much heat (other than light surface heat) to the inner hub in an attempt to remove it, as, amongst other things, heat may destroy the prop shaft seals and you may also end with a bent shaft.
Once the inner hub is out, clean very carefully the propeller shaft splines (you may need to use a stainless brush) and grease them well before installing another propeller."
