Yamaha Outboard repower

[seashellbb63@yahoo.com]

Want to repower my 1996 Keywest Oasis21 deckboat with a F150 Yamaha 4 stroke but worried about the extra weight. Boat is rated for 150hp but that was before the 4 strokes. It has a 125 mariner on it now but firing problem is going to cost $1K. It has a 20in transom. Any feedback will be appreciated!

 

[99yam40]

I think fixing the 125 would be a lot cheaper