Johnson 4R72S whoops!

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,226
Re: Johnson 4R72S whoops!

You have a choice: Either use the soft pin and change it every time you contact one of those branches, or use the correct pin and keep going after contacting the branch. Personally, I've never really enjoyed changing shear pins on the water. Even though the old Martin motors were kind of cool in that they would swing around to put the lower unit inside the boat so you could reach it.
 

Grem

Seaman Apprentice
Joined
Oct 6, 2008
Messages
45
Re: Johnson 4R72S whoops!

Yes, I take your point. Being that the motor is so old, it would be a shame to mash the rubber or even worse strip the splines on the shaft if the prop bites into a branch. As I mentioned, the pin that was in there was magnetic but broke into three clean pieces. Maybe some of my stock stainless rod would be too strong for that application.....hmmm.:confused:
 

Rick.

Captain
Joined
Jul 30, 2006
Messages
3,740
Re: Johnson 4R72S whoops!

I feel as though I have to speak up here. When you removed your prop you found three small pieces which used to be one completed pin, correct. Now suppose you use a softer metal like copper, brass steel or whatever. If you hit the same submerged object what is going to happen to your home made pins? Best case is they will break into three seperate pieces. Worst case is they won't shear and instead bend and try to wrap around your prop shaft. How are you going to punch it out once it becomes bent. How many parts are going to get wrecked trying to get the bent pin out? If the pin bends it will probably wreck the nylon it goes through. I'm all for saving money and will when given the chance but I'm going to continue to use OMC shear/drive pins for my prop.
Rick.
 

Bear 45/70

Seaman
Joined
Nov 2, 2008
Messages
59
Re: Johnson 4R72S whoops!

I feel as though I have to speak up here. When you removed your prop you found three small pieces which used to be one completed pin, correct. Now suppose you use a softer metal like copper, brass steel or whatever. If you hit the same submerged object what is going to happen to your home made pins? Best case is they will break into three seperate pieces. Worst case is they won't shear and instead bend and try to wrap around your prop shaft. How are you going to punch it out once it becomes bent. How many parts are going to get wrecked trying to get the bent pin out? If the pin bends it will probably wreck the nylon it goes through. I'm all for saving money and will when given the chance but I'm going to continue to use OMC shear/drive pins for my prop.
Rick.

For a temporary fix the brass or bronze will work fine. The only steel pins I know over were in the sterndrives and better than a 1/4' in diameter. OH yeah, I've removed plenty of bent pins. It ain't no big deal. If the pin was as hard as you suggest the rubber hub would slip, just like it is suppose to.
 
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