Thoughts on the brass shear pin and the monel drive pin for OMC engines

[billy-j]

For many years on my mid 50’s Big Twin engines I used brass shear pins made from 1/4 inch brass brazing rod with no issue. If I hit something with the propellor the brass would shear with no damage to the motor. I know the 1956 Johnson 30 HP. calls for a drive pin and I think it’s made of monel metal.  Something like stainless steel. A friend of mine with a 1958 Johnson 18 HP. had a monel pin in his motor and hit something and now the lower unit has an internal problem and the pin bent but did not shear. I would like some opinions on using brass or the monel drive pin.

[Waunaboat]

Regardless of whether or not they call for a brass pin, if it has worked and sheared when necessary, I would continue going with a brass pin.  I prefer to err on the side of caution whenever possible in any field of life.

"Outboards seem to multiply exponentially..........I find that for every finished project, there are two more waiting to be completed."

[joecb]

For what we typically do with our hobby motors… like no transatlantic voyages, go with brass on the larger motors. I even use aluminum shear pins on the small put -puts.

Joe B

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