Reply To: Winter Project 1957 Johnson Javelin

[Don]

David Stanton wrote:

The upper and lower gearcase halves are final machined together at the factory, giving a matched set, so, if you can, replace both halves with a set from another motor, instead of just replacing the cracked half.   Usually it works to replace just one half, but you may have trouble getting it sealed good.

Dave

Replacing just one half of the gear housing is a big risk, especially on a higher HP engine like this one…