i had a bit of a nose in crash. i took my engine apart to clean and inspect it. now i tried to put a new prop on. when i tightened it down the prop would not move. it seemed to tighten too close to the crank case now. i have also noticed that there is lateral movement of the crankshaft. that is it moves fore and aft about 1/32" maybe. is this movement normal? i never noticed it doing that before. it is an evolution .40 engine. not the nt version but the one that came with the trainer.

How much disassembly did you do on the engine? Did you remove the crank? If you did not the crash probable moved the crank and that may be causing your problem. Remove the prop and back plate. Using a wooden dowl placed against the back of the crank tap it lightly with a hammer and see if it moves forward and reseats. End play in a crank is normal and desireable. It tells you that the inner races of the bearings are not pinched together or forced apart. 1/32 is a bit much but still may be ok. A few thousands (4or5) is more desireable. 1/32 in a ball bearing engine may indecate bad or damaged bearings.

Probably just drove the crank back a bit in the bearing races. Do like djlyon said and remove the backplate, and use a dowel and hammer to tap the crank back up against the bearing. Remove the drive washer before doing so, and then reinstall and feel for the play. If the bearings were damaged you should easily feel them (1/32 is a LOT of play).

AJC

thanks for the great suggestions, but i already fixed the problem. turns out i was missing a washer that goes between the front bearing and the prop driver. good to go.

NEVER use a hammer to install or remove a crankshaft, even with a wooden dowel. The hammer blows can cause the ball bearing to bounch hard on the bearing race and "nic" one or the other. To assemble, either press the parts together smoothjly in a vise, or heat the engine, then "overtighten the prop to pull the crank forward. To releave the pressure on the bearings, lightly tap the end of the prop shaft, with a prop tightly bolted on. Place a nut over the end of the prop shaft threads so they are not damaged from the hammer.

Good call Mike I like you press the bearings in place, or use a bolt/steel washer pull system. The only hammer I use is involved is in removing the old bearings and even with this method I use my custom (ground to size) deep well sockets, that only put pressure on the outside of the bearing case. Even distribution of the load on the outside of the bearing case is the only way to insure an undamaged bearing or engine case.

Locking it up in a vise only takes a extra few min and is wll worth the time IMHO.