Reply To: 1956 Johnson 30hp Rebuild

[olcah]

Bob,

https://www.aomci.org/forums/topic/1955-25-hp-johnson-loose-conn-rod-bushings/

In the above thread Garry in Michigan said that the specs for the wrist pin bearings changed during production in 1956 :

” The suppliers specifications changed and the new bearings had the same part number but were better quality. The only ’56 early serial number Big Twins that you would find with bad wrist pins today would be in an old dealers back room still in the sealed factory box.”

If I misinterpreted his words I welcome correction but in the meantime I am hanging my hat on this and so far I have had no rod bearing problems on any of my three RD18s.

Hope this helps.