Re: Replacing the Power Head for my 70 HP Force. Can I go bigger?
Re: Replacing the Power Head for my 70 HP Force. Can I go bigger?
While to engine block is the standard 3 cylinder Force and the mounting bolt pattern is the same, If you have the Mercury controls, and with a 96 engine they most certainly are, the controls and mountings are different. Therefore, you are limited to using another 70 engine unless you want to get into lots of modifications. Do-able and not too difficult, but custom work and time consuming.
I have the same engine (1990 something--I forget the exact year) and have bored the block. I am currently contemplating whether or not I want to buy new pistons for it or swap in a 90 block.
I just re-read your post. Did I misread it or did you edit it? I don't remember seeing the sentence about the crankshaft. At any rate, a crankshaft from an 85 or 90 will fit in your block. If it is just the flywheel threads (for the nut) then yes, you can swap. You will not gain any horsepower because the cranks are all the same stroke.