I have over a 1000 hrs behind VW engines and I am not any more nervous flying with them as compared to a Lycoming or Continental. Keep up on maintenance and pay attention to the valve train and head setup.
I have removed the prop hub many times while get everything setup the way I wanted. My crankshaft and hub is a knock off of the Great Planes Force One setup, by TOC in Florida. When I got the engine the hub was not properly seat to the taper on the crankshaft. The back of the hub would hit and the rest of the taper was not in contact with the shaft. I had a machine shop take 1/16 of an inch off the back of the hub, and this allowed the whole taper to seat. I then set the crankshaft in an old flywheel and lapped the two together until there is zero run out on the prop hub. When properly lapped, you can set the prop hub on the crankshaft and it will require at tap with a mallet to get it back off. Once it has been torqued, it will not move. As Mark said, the keyway is only for indexing. To pull the hub back off I put a metal spacer against the crankshaft inside the prop hub and and torque a gear puller to the outside of the hub, against the spacer on the crank. Must be careful not to over torque and bend the prop hub, then I hit the top of the nut on the gear puller with a small sledgehammer. Pops right off every time with no damage. As I said, I have done this many times during setup with this current engine and now have over 250 hours on it. Also, my hub seal does not leak so far. Roger Bulla rbulla2 at wic.net
