1995 Islander 268 re-power

[Cam Ena Sue]

Have read a lot of discussions on this topic but have not seen any with my particular case. I am trying to decide repowering with a single yamaha 300hp versus the new yamaha 350hp. The boat currently has the motor it came with from the factory (Yamaha 250hp 2 stroke) - and I have always felt its underpowered. I am concerned the single 300hp will have the same issue, however my local yamaha dealer seems to think the 350hp is not necessary and the 300hp would do just fine.

In a perfect world twins would be the call but unfortunately not in the budget so deciding between which single hp is where I am at.

Thoughts or anyone with an Islander and single 300hp would be awesome feedback.

 

[Stephnic]

I repowered my 1998 268 with twin F150’s the boat ran great. I think the 300 would be a perfect fit.

 

[Cam Ena Sue]

I repowered my 1998 268 with twin F150’s the boat ran great. I think the 300 would be a perfect fit.

Appreciate the reply!

 

[PukeNreel]

Most people in the industry Ive talked to say the 300 Yamaha 4.2 is on top of the list for reliability and makes great power! If it were me and the price wasn’t to much different I would consider the 350, seems like it’s based on the 4.2 platform mostly.. you rarely hear someone complain about having too much power. I have a 265 express with twin 225s, it does fine but I wouldn’t mind twin 300s!

 

[Mustang65fbk]

One thing to consider, if I’m reading this correctly, is that the Yamaha F300 doesn’t come in a 25” digital control version, and is mechanical only? If the length of your current outboard is 25”, which I believe it is and you’re looking for digital controls, that would be something to consider. Maximum horsepower for the hull is 400 hp and if the boat currently handles just fine with the Yamaha 250 on there, I imagine a 300-350 hp outboard with slightly more weight will do just fine as well. I would also look into a Mercury 300-350 as well as also look at Suzuki. Suzuki is currently offering a 7 year warranty on their higher horsepower outboards until the end of the year. The Mercury ProXS 300 is 511 lbs and the 300 FourStroke series is 527 lbs, which are going to be the lightest 300’s out there. You’d likely also save a considerable amount of money going with Mercury or Suzuki over Yamaha as well.

 

[family affair]

There will be a noticeable difference from a 300 hp single to a collective 300 HP in twins. Collective engine displacement will be a major contributor - 4.2 liters for a single vs 5.4-6 liters for twins depending on and assuming 4 cylinder models. That much displacement makes a big difference in mid-range power.
If you have the budget for a new f350, I would strongly encourage you to consider twin Mercury 150s for your hull. Your out the door cost for the 150's might be less than the f350 with substantial benefits.
I went from f150s on our 270 (268 replacement) to twin df200ap's. The performance is phenomenal, but it is not the right engine for your hull due to weight. The mercs are much lighter - similar to the 2 strokes your hull was engineered for.
There have been other members with 270s that used higher HP singles and fought prop torque issues. It's possible there was a fix, but the member could never find it with a Verado 350, and then bought twins.
A single 300 can get the job done, but if I'm buying new, I'd go twins for the win.