How to keep the prop nut from backing off?

[mr4570]

I bought a new prop but it does not have any place for the ears of the tab washer to fold down into, nor does there seem to be any room for any sort of insert capable of receiving the tabs. Also, the prop shaft does not have a hole for a cotter pin.

Can I drill a hole through the prop shaft (for a cotter pin) without causing any damage to the motor/lower unit? Or is there a better way to keep the prop nut in place?

The motor is a 1996 Force (by Mercury) 120HP outboard.

 

[Scott Danforth]

Re: How to keep the prop nut from backing off?

isnt there supposed to be a splined washer that the tabs fold into?

 

[Frank Acampora]

Re: How to keep the prop nut from backing off?



You can TRY to drill the propshaft but they are witches with a "B"

Better solution is to buy a Nylock prop not and occasionally replace it. A new nylock will not back off provided you tighten it correctly and do not have any play in the prop.

These are off an older Force but you should notice the nylock. Different sized nut but the principle is the same. I have never had a problem even after repeated removals.