93 90hp Force motor powerhead swap with 91 powerhead?

[balmfort]

The powerhead in my 1993 90hp Force dropped a cylinder and cracked the block. I acquired a 1991 90 complete motor but it has different mounting brackets and no power trim. So the question I have is can i swap the powerhead from the 91 onto my 93 motor? I know the electronics are different but I am wondering if I can use the newer electronics which I believe is a Prestolite system. I know there are some very knowledgeable Force outboard guys that use this forum. any and all help would be appreciated
phil

 

[Nordin]

Yes, the 1990 powerhead will fit, the bolt pattern are the same for both of them.

The 1990 will have the Prestolite system and you can use it, maybe you have to rewire the harness at the keyswitch. The 1993 may have the Mercury ign.system.
1992-93 Brunswick changed from Prestolite to Mercury system.

I am not soo familier with the Mercury system but many at this forum prefer the Mercury system and mean it is a better system then the Prestolite.

Changing the 1990 powerhead to Mercury system would not be a big deal.
Maybe you just need to swap the top bearingcage where the stator and trigger are mounted and the flywheel.
But as I mention I am not so familier with the Mercury style system. Have just worked with it one time.

 

[balmfort]

thanks for the input. I do think I can use the ignition / electrical system from the 1993 motor. I've been looking at the 1990 and the gear linkage and throttle connections appear a little different than the 1993. I want to use my original cables and electrical harness as I know they all worked before the powerhead failed. any suggestions on this forum where to find good parts illustrations on these 90hp motors?
phil

 

[pnwboat]

"Google Images" might be a place to start. Some of the OEM manuals?

It appears that both motors used the Mercury Switch Box ignition system, but I'm not 100% sure about that. If so, then the swap should be relatively easy.

 

[balmfort]

No Title

thanks for the replies. I have the powerhead off the 1990 motor leg and it looks like it will bolt on the 93 no problem. Next challenge I have is that the brackets that hold the throttle and gear shift cables are different. Anyone out there have some pictures of the 1993 cable attachments to the powerhead? I dont have the original block any longer I I was not the person who torn down the 93 motor. any help would be appreciated.

attached are the pictures of the 1990 cables and brackets
last picture is of the 1993 cables without the brackets

 

[jerryjerry05]

Find a parts diagram.(boatsdotnet) has good ones.
​Force is found under the Mercury tab.
​Then find the parts you need and then e-bay has some parts.