Repower again 2+2 yrs & models

[1966starcraft18ft]

Hey all. So this spring I repowered our 1998 MonArch SunSpa260 pontoon from a 1988 US Marine Force 125 hp to a 1999 Mercury 125 hp. Well, piston in cylinder #1 left the chat through multiple holes in block and intake/reed assembly. So now I’m figuring out another repower.
I didn’t mind the engine except for one thing, the 2+2 part.

Now, I create this post in hopes of learning and helping others wonder my very question.

What model yrs & sizes had the 2+2. The wife & I didn’t care for the harsh engagement of the bottom two cylinders and the shakey idle. I’d like to stay with Mercury just cuz I already have it rigged and controls are kinda spendy in my opinion.

 

[racerone]

All the inline 4 with the 4 carburetors were the 2+2 configuration.---Not the best motor for a pontoon.---Best option in my opinion is an OMC model V-4 of crossflow.----Find one to rebuild and you will have a smooth running motor for 20 seasons.

 

[Texasmark]

All the inline 4 with the 4 carburetors were the 2+2 configuration.---Not the best motor for a pontoon.---Best option in my opinion is an OMC model V-4 of crossflow.----Find one to rebuild and you will have a smooth running motor for 20 seasons.

I agree having had both. Probably my best 2 engines, both bought new, were a 1972 Johnson 125 V4 cross flow and the 1970 something (forget the exact year probably '78 or '79) Mercury 850, forget which 3 or 4 cyl., probably cross flow too. Cross flows liked their fuel but otherwise were pretty much bullet proof.

I had the 3 cylinder 2002 Merc 90 HP and 115 (2+2) and they ran like a scalded rat but otherwise were finicky, especially on first start after sitting. My avatar is the 90 performing.

 

[1966starcraft18ft]

10-4. Thank you for the info. So if I go up to a 150 same yr, it won’t be a 2+2.

 

[Chris1956]

Gee, how about a 2 cycle Merc V6? They are a proven design, they range in HP from 135HP to 200HP, and they likely fit your current controls and wiring.

 

[1966starcraft18ft]

I’m game for a v-6. Then I don’t have use a setback plate. The inline 4 motors hit my sundeck.

I’ve contemplated a 4stroke but they are like an extra 100 lbs