80s Islander 2.5 to 4.3 swap help

[pntbtrjllytme]

Hello
Ive done a couple starcraft restores and I recently did a 1990 Lund and my next project is a 221 Islander. I dont have it just yet so no pics but will post progress when I get it. Its currently my brothers and he will be dropping it off this December. That being said it has a 4cyl motor in it and it just runs a bit rough. The boat actually used to be up here with me so Ive been in it a few times. I have on hand a perfectly good 4.3 and a leg for it. What Im wondering is has anyone done this and have any pics or tips they could hook me with? Im mostly concerned with the transom as I will be replacing it but I have 0 clue how to go about cutting the keyhole in the right spot. You guys have helped a lot in the past and Im hoping you can help me pull through with this build as well. Thanks in advance!!

 

[Scott Danforth]

unbolt drive
remove 2.5 liter
remove transom shield

check for transom rot prior to proceeding

install 4.3 transom shield
install 4.3 motor and support with shop crane
align 4.3 motor
build mounts for 4.3 that fit
install mounts
re-align motor
install drive

 

[pntbtrjllytme]

I really need help with the keyhole pattern/location the rest Im very familiar with

 

[Omineca]

Is this any help?

Mercruiser Transom Template

It would save me a lot of time if i could print 1:1 copy of template ( i have access to wide format printers) rather than make what was right/wrong from scrapped transom or what was left out of it. Ive seen i believe template for Volvo on pdf., does anyone have access to mercruiser? Thanks

forums.iboats.com

 

[GA_Boater]

What is in her now?

 

[pntbtrjllytme]

Is this any help?

Mercruiser Transom Template

It would save me a lot of time if i could print 1:1 copy of template ( i have access to wide format printers) rather than make what was right/wrong from scrapped transom or what was left out of it. Ive seen i believe template for Volvo on pdf., does anyone have access to mercruiser? Thanks

forums.iboats.com

Awesome yes thank you sir!

 

[pntbtrjllytme]

What is in her now?

An old beat up 4cyl. Think its a 2.5 but not sure its been a while since Ive been in it. But I really feel its underpowered for a 22ft boat

 

[GA_Boater]

An old beat up 4cyl. Think its a 2.5 but not sure its been a while since Ive been in it. But I really feel its underpowered for a 22ft boat

What brand?

 

[pntbtrjllytme]

What brand?

Mercruiser

 

[GA_Boater]

You don't need a template. The keyhole is the same for all Mercruisers except for a couple of minor things like extra holes for bolts.

 

[pntbtrjllytme]

You don't need a template. The keyhole is the same for all Mercruisers except for a couple of minor things like extra holes for bolts.

Ok good to know. Do you know if the height is the same as well? The transom should come out in 1 piece. I hope lol. If it does I can just trace the keyhole location onto the new transom with the new bolt pattern. Correct? And thanks for the help btw much appreciated! The last 2 boats I did I did them in a 1stall garage. We just koved this year and I have a whole barn to work out of wirh new tools so this project should be a lot of fun if I can get this motor set in

 

[Scott Danforth]

keyhole exactly same.

see post #2 for process

 

[pntbtrjllytme]

Hey guys. Thanks for the info and sorry for the lack of replies I had to run out of town. But I do appreciate the feedback. I thought Id post some pics of the boat and motor. Its actually a 3.0 as you will see but here she is!

 

[dusted_ya]

... Im mostly concerned with the transom as I will be replacing it but I have 0 clue how to go about cutting the keyhole in the right spot. You guys have helped a lot in the past and Im hoping you can help me pull through with this build as well. Thanks in advance!!

When you remove the old transom, use it as a template easy peasy! Also make sure you paint the WHOLE thing with a couple coats of Gluv-It.