1972 Johnson 40HP Shear's pins like crazy

[gilbertmilone]

Hi All, Just a little update on the shear pin problem. I posted a message earlier regarding the wrong motor. My motor is a 1972 40HP Johnson. Model 40EL 72E, the lower unit shaft shear pin hole is a bit worn, so when I put a new pin in, there is some play between the prop and the shaft. When I open the throttle up the shaft moves and snaps the pin. Sometimes it happens when I switch from forward to reverse, sometimes when I switch into forward, sometimes when I accelerate. Does anyone have any advice as to how I can solve this problem? By the way, I've been using bronze pins. Should I switch to stainless? <br />Thanks for the help so far,<br />Gil

 

[almost retired again]

Re: 1972 Johnson 40HP Shear's pins like crazy

Hi Gildomilo;<br />It kinda depends on where you operate the engine; salt water or fresh. It sounds like the hole through the prop shaft has become enlarged. You can go to a larger shear pin or go to a piece of common braze rod stock that will fit the hole snuggly, or if you operate in freash water even a piece of large nail will work. However I don't recommend this as the nail will tend to rust quickly.<br />Hope this helps

 

[gilbertmilone]

Re: 1972 Johnson 40HP Shear's pins like crazy

I use the boat in both salt and fresh water. Mostly salt I would say. Wouldn't a nail be too hard?? <br />-Gil

 

[badasselectric]

Re: 1972 Johnson 40HP Shear's pins like crazy

How many strings do you have running on this?

 

[gilbertmilone]

Re: 1972 Johnson 40HP Shear's pins like crazy

Two I guess. I started a second one because the heading of the first one was wrong. Sorry I didn't mean to confuse anyone. <br />-Gil