Replacing piston pins and rod bushes on an M696

[CaLyPsO]

I am working on my M696 engine and swapping out the entire vertical cylinder and piston for some good used parts but now I am questioning what to do with the little components.
I was planning on just reusing the piston pin that came with the used replacement piston. But should I buy a brand new piston pin instead, and while I have things apart, is it a good idea to also replace the original connecting rod bush? I want this repair to last. And another thing I am not sure about is the piston pin on the horizontal cylinder which I am not replacing because I am not sure about the correct orientation when it goes back in. Does the direction of the piston pin really matter on that horizontal cylinder, and what are the signs that a connecting rod bush definitely needs to be replaced? Thanks!

 

[black bear]

Buy a new piston pin instead of reusing a used one coz new pins removes your doubt about unseen wear or dimensional issues. Then have the connecting rod bush replaced coz it's a precision machine shop job, Do Not, and I mean, do not attempt to swap it unless you can also ream it to the exact size for the pin. You can check the bush by ensuring there's no wobble or play when you insert the pin, and any visible scoring or scuffing is a clear sign for replacement.

Check this video for general engine piston maintenance:

 

[Alan]

Well, short summary for a lasting repair is to replace the pin and have a professional machine shop replace and correctly size the small end bush on your vertical cylinder rod.

 

[CaLyPsO]

Thanks! I'll just bring this to the nearest machine shop in my area. I am not confident that I can correctly size the small end bush on my vertical cylinder rod.