Johnson to Mercury outboard conversion?

[imported]

Currently have a 1986 Johnson 120 and am thinking of repowering to a 2015 115 hp Mercury.

How far off will the bolt pattern be on the transom and should I care as long as the old holes are patched appropriately?

Will I be able to use my existing controls? Is there a way to "convert" them some how?

Thanks for you help

 

[gm280]

import, I'd be really surprised if the two mounting patterns actually lined up myself. But anything can happen. However, if you have to drill new holes, you can seal the old holes and happy boating...

 

[Faztbullet]

Mounting holes are the same but controls will not interchange or convert...