powehead swap 83 90hp to 90 88 spl

[99z286spd]

As stated I'd like to swap powerheads but in reading the seloc manual it is very vague on how to remove the powerhead from the outboard assembly. I have the tools and general knowledge I just need some pointers from someone who has done this before.
The manual says to remove two bolts and two nuts and lift....will it bethis easy? I have already pretty much stripped the block of starter and electrics and such items any help appreciated thanks

 

[99z286spd]

Re: powehead swap 83 90hp to 90 88 spl

Anyone? Ideas? pointers?

 

[99z286spd]

Re: powehead swap 83 90hp to 90 88 spl

I just looked up in the parts catalog...the exaust gasket to the block on both engines is the same part # so at least it will fit i just need help on HOW to get it apart and put it together Thanks in advance.

 

[emdsapmgr]

Re: powehead swap 83 90hp to 90 88 spl

It's pretty straightforward. Uncouple the shift shaft under the bottom carb. Remove the front and rear lower cowling covers to expose the powerhead mounting bolts, nuts. Remove a total of 4 nuts (2 front of powerhead, two rear.) Remove two short bolts toward the front of the case. Remove 6 long bolts, 3 on each side. Install a 3-leg puller on the flywheel and lift with a chainfall. You will have to swap the outer exhaust cover. The 83 cover won't have the mounting bosses for the new style power trim box. If you have the early 83 carbs, I'd use the 90 carbs, since they use the fuel primer system which helps cold starting and for winterizing. The only exception would be if the 90 carbs have the plastic carb bowls-then stick with the 83 carbs. All plastic bowl carbs will (eventually) warp and leak fuel. They can also cause internal air leaks which can cause it to run lean, and damage the powerhead.

 

[99z286spd]

Re: powehead swap 83 90hp to 90 88 spl

Wow thanks!
Just so you know...I decided to put the whole engine on my boat and took the 83 off. The new (1990) engine was in good shape and better looking. Problem is....I found gear oil leaking from the inside of the lower end. I think the shaft seal is bad and the prop shaft spins kinda "rough". I pulled the 4 bolts holding it in but couldnt pull it out...I guess i need that special puller. So tomorrow I am going to swap the whole lower end completely. It will be better anyway because i just had my origional (1983) lower end redone new water pump and seals and gear fluid. Do you know roughly how much it will cost me to rebuild the lower end at a marina?(@ 100$ an hour) A buddy did my first one but he is no longer around. Thanks again