new Acme 1442 installed

Kerry,
I don't see that you lapped the new prop on. You should have so give it a try. If the cotter pin still won't go in and you're uncomfortable with backing off the nut, Go with the brass nylock.

You must have missed the numerous times I've mentioned that a proper fit prop is held on by the taper and the reason pullers are needed to remove them. I've backed off nuts so the cotter will go in many times.

Just incase you what to take a look at lapping, here's proper prop installation

if you use a lock nut-dont use a stainless one

SJ - I suggest doing the lapping step. It doesn't cost much, doesn't take much time, & assures that your prop won't come off. The castle nut really is just a 'backup' & doesn't need to be tight against the prop.

It's possible that lapping would remove enough high spots that the prop will go on little further & your cotter pin will line up as torqued.

Any one have any suggestions on getting the castle nut to index properly once the prop is torqued on the shaft? I Installed a new 1442 today on my 1994 ski and have run into a problem of not being able to get the cotter pin in since the hole in the shaft and the slots in the nut don't line up. I followed the instructions form Acme that came with the prop. Put the prop on with out the key and then marked the shaft. Then put the key in and reinstalled the prop. It seem to seat very nicely and snugged right to the mark. The instructions said not to torque passed 30 pounds. well 25 pds caused the hole to be coved by the nut. Going to 30 did not change a thing and I cannot get a cotter pin in. Are there any shim washers that can be used to get the hole and nut to line up with the proper torque? I did have to use a block of wood to hold the prop any problem with this? Do you think lapping the prop would change enough to align better? How tight should the nut be torqued? Any help would be greatly appreciated.