90 into 70

[gillybabe]

Can you put a complete ignition system from a force 90 into a force 70 and will it work?

 

[pnwboat]

Re: 90 into 70

Depends on what year the motors are. Biggest problem is the stator mount with crankshaft seal and the flywheel. These were changed when Mercury took over. Early model motors had 20 pole stators and solid band magnet in the flywheel. Later models had 12 pole stators and six separate magnets in the flywheel. The stator mount with crankshaft seal for the 12 pole and 20 pole stators are also different. While the outside diameter of both stators is the same, the hole in the center of the 20 pole stator is much larger in diameter than the 12 pole stator. The wiring is slightly different too, but from what I can see, it's adaptable. The mounting plate that hold the coils and CD modules may have attachment holes in different positions to secure it to the block too.

I have a project to swap the early Prestolite ignition system w/blue coils and CD Modules on my 1988 125HP to the later 1998 Thunderbolt style ignition system. I have all the parts but I don't want to attempt the swap in the middle of boating season.

 

[moparman]

Re: 90 into 70

pnwboat, I have a 1988 125hp also, this sounds like a great swap, please keep us posted on the progress as you do the swap [maybe with some pic's too],If you could post prices ,that would be helpful . looking forward to your post. MOARMAN

 

[pnwboat]

Re: 90 into 70

Sent you a PM moparman.