Help going from a 90 hp Force to a 115 hp Merc

[tswheezer]

We have a 1991 Bayliner we recently purchased with a 90hp 1990 Force outboard. We thought we could repair the motor but it is fried. Only some of the electronics. We have found a 115 hp Merc as well as other motors we may be looking at replacing with. Would we then have to replace all the steering and throttle cables as well or will the other motors be fine with the cables that are there already on the boat.

If we would need to repalce how big of a job is it for us who are handy to do? Otherwise if we take it in to be done, how much are we talking?

Thanks!

 

[Chris1956]

Re: Help going from a 90 hp Force to a 115 hp Merc

The steering and fuel systems are easily modified to work with the Merc. I am not 100% positive, but you will likely need to get a new control and wiring harness.

The control cables themselves may (may) be compatable. You could look up replacements for the Force and the Merc and see if they are the same.

The swap out job is pretty easy.

 

[Goneflyin]

Re: Help going from a 90 hp Force to a 115 hp Merc

I did the 90hp Force to 90hp I6 Merc (1985) swap about a year ago on a 92 Maxum. If you have or can get the manual for the controls they can be set up for most standard engines, it requires pulling the shift lever unit and moving links in it. For the wiring I bought a terminal block from an electronics store, mounted the block under the cowl. I had to make a few jumpers for the merc side but it was pretty simple. Tach also worked fine. Mounting the merc I had to drill new holes for the top mount and used 3/8 bolts on the bottom which line up with the Force holes so I didn't have to drill the bottom, the holes were coated with epoxy and then used 3m 4200 to mount the motor.
I rebuilt the Force (broken rings) and sold it but what a difference between motors. The Merc was a major improvement in hole theshot and 7 mph better on top end, the numbers on the Force were the same as the original owner said he got. So a 115 should run real good.

Bill