1960 and 1970 johnson 40hp crankshaft interchange.

[RabboJens]

Have the two engines, the 70 has a bad taper and flywheel, I know that parts differ and so do the crankshaft but will I be able to drop the 60 one into the 70 case? The 70 is a selectric shift can I use the complete 60 powerhead on there instead (changing fuel pump, bypass covers etc etc).

 

[Chinewalker]

Depending on the 1960 powerhead, the crankshafts could be similar, or quite different. I believe there was a recall on the 1960 motors due to cranks breaking. They originally came with a smilar crank used going back to the early 1950s 25s. Bumping the ponies from 25 to 40 over the years resulted in crankshaft failures. They beefed up the cranks for 1961 & up motors, and replaced a lot of powerbeads for the 1960 models.

That said, I'm not even sure the 1961 and 1970 cranks are close enough to swap around... Might be a case of get them both apart and see....

To answer the second part of your question, they added a lot of bells and whistles between 1960 and 1970. The bolt patterns should be the same, but there may be some small changes that would make the swap a challenge.

 

[racerone]

There are lots of good used newer 40 hp cranks around.----I believe the 1960 model has a smaller taper.-----Look for a newer one !!----Your location ?

 

[RabboJens]

Looked att Them both, No go, they are different. You certainly know your stuff. I Will consider getting new wheel and shaft bit it costs a bit to get Them to Sweden. Thanks for replys!