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

I’m contemplating the early 2000’s Johnson/evinrudes that are carbed, mercury 2 stroke efi 150’s( no optimax please) used Yamaha 150 4 strokes cuz of their reliability but will have to add a sport toon to help keep the extra weight afloat.

Believe I can get away with a 2 stroke 150. From what I can find, the 24’ version of my pontoon is rated for up to 135 hp( my data plate is not legible)

 

[Texasmark]

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

The 2+2 was the 4 cylinder produced something like 9-10 years (I read somewhere) in 115 and 125 HP. 150 is a V6.

 

[1966starcraft18ft]

10-4. Don’t get me wrong, my 125 was a good motor. Heck, I could back troll my pontoon without any issue at all and if it was just me, wouldn’t give two turds if it idled a lil goofy but the boss didn’t like it.

 

[Texasmark]

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

I’m contemplating the early 2000’s Johnson/evinrudes that are carbed, mercury 2 stroke efi 150’s( no optimax please) used Yamaha 150 4 strokes cuz of their reliability but will have to add a sport toon to help keep the extra weight afloat.

Believe I can get away with a 2 stroke 150. From what I can find, the 24’ version of my pontoon is rated for up to 135 hp( my data plate is not legible)

The 2+2 has a 4 cylinder stack. A V6 only has 3 and I would imagine the upper and lower parts of the engine are (pretty much) the same including the distance from the clamp bracket to the top of the engine cowl would be 1 cylinder shorter. The V6 came in 135 HP but I never saw much chatter about them so I guess they weren't that popular like the 150. Since the rating plate isn't legible then more than likely you wouldn't have a problem with being overpowered, especially on a toon.....opinion.

 

[Chris1956]

The Merc 135HPV6 is/was a 2.0L engine. Merc initially made 2.0L versions of the 150 and 200HP V6 engines, but I believe they lacked the torque expected. Those blocks were upgraded to the 2.4 and finally the 2.5L blocks.

The 135HP 2.0L motor is a good one for the appropriate planning hull. I would think a 'toon being displacement or semi displacement, would benefit from the higher torque of the 2.5L blocks.