Coupler

[bcguy]

Hi... just noticed some play in the shaft at the coupler which seems obvious is that the set screws have become loose. Just wondering about simply drilling a hole through the coupler and the shaft and then slipping a bolt through (as well as re-tightening the set screws against the shaft). My shaft is stainless 1.25 inch. Engine is 3 cyl 27 hp yanmar.

The bolt would be similar principle to cotter pin concept except much thicker but not too thick to weaken shaft... thinking of 3/8ths...

...thanks

[capngeo]

A lot of commercial applications do just that.... as well as using a "collet" type flange. You're fine doing what you say, but a word of caution: The cast iron and stainless are vastly different in machinability. Very easy to drift off the drill when boring in the boat.

[perchance]

If they are socket head set screws you can put one on top of the other to lock it down.