lower unit bolts

[mnpilot]

I have what appears to be a 1954 Johnson 10 hp missing the 4 lower unit bolts. Can anyone tell me what replacement bolts to use?

 

[racerone]

Stainless bolts from any hardware store.----They are 1/4-20NC thread.

 

[mnpilot]

Thanks. I'm guessing about 3/4"

 

[racerone]

This should be easy to determine.------Try some bolts in there and get maximum thread engagement ( count number of turns )