Sportsman 18 115 HP Yamaha - Should I be Concerned?

[bcahn19]

Other threads have brought this topic up, but wondering if anyone can speak to an older Sportsman 18 with a 115hp Yamaha 4 Stroke. How does it handle? Is it a constant struggle on plane? Are you constantly WOT? I understand this boat functions best with a 150hp Yamaha. But for a potential boat owner whose goal is shorter day trips with 3 - 4 people, will the 115hp 4 stroke get the job done, or have others experienced issues getting to plane or causing the engine to undergo stress on this model?

I've noticed newer models are almost always 150hp, so I am concerned. I don't need the boat to be a speed demon, just want to ensure the boat will still plane with the 115hp 4 stroke. Would consider repowering in a year or two, but would use the 115hp for the time being. Thanks for any feedback.

 

[dainlaroche]

I have a 150 hp 2-stroke on the larger, heavier 209 which is more than enough for what I want to do (fishing, towing the kids on tubes, cruising). That 115 engine should be fine on the 18' boat and be pretty efficient on gas too, although I do not have first hand knowledge. I had a Yamaha F150 four stroke on my previous dual console 20' and it was a superb engine.

 

[bcahn19]

Thanks. Appreciate your feedback. I love the hull design and its perfect for my needs - just want to ensure the 115 is 'adequate' for a few years before I re-power.

 

[seasick]

Describe what a "constant struggle' means. There may be things that are easy to modify as well as check. Also tell us what your revs are at WOT. You shouldn't have to run at WOT as the norm

 

[DennisG01]

115HP on a little 18-footer will MORE than adequate - you'll be just fine! If you find, based on the load you put in the boat, that you need a better hole shot or ability to stay on plane at lower RPM's, you can install Smart Tabs for about $200 and they will make a HUGE difference.

 

[seasick]

115HP on a little 18-footer will MORE than adequate - you'll be just fine! If you find, based on the load you put in the boat, that you need a better hole shot or ability to stay on plane at lower RPM's, you can install Smart Tabs for about $200 and they will make a HUGE difference.

Dennis, do you really recommend smart tabs?

I had to read the original post again twice to finally see that he doesn't have that model boat and these issues; but rather read about them someplace. If that is the case, I would also agree hat I don't see why the boat would have those issues with the F115 motor

 

[DennisG01]

Dennis, do you really recommend smart tabs?

Yes! Absolutely! I have used them on my own boats, family and friends, and countless customer boats. They do EXACTLY as they advertise and they do it really well. Great bang for the buck! Inexpensive and only takes about an hour to install. Full hydraulic trim tabs are great - but those run $600 to $800 for parts and easily take (an experienced person) a solid half day to full day to install.

 

[bcahn19]

Dennis - thanks very much. Will look into Smart Tabs. Much appreciated.

 

[DennisG01]

Regarding HP... if you go back some years, there was probably the same question being asked between a 90HP and a 115HP for a given boat model. I think we, as a whole, have just gotten a little spoiled (not that that's a bad thing!) over the years. And then, if someone only does online research, without real-life experience, it can cause you to wonder.

The other thing that will happen is you'll find that forums are absolutely notorious (not so much here, I've noticed) for people spouting off or simply regurgitating information that they read (regurgitated from someone else... regurgitated from someone else) somewhere else and eventually people start to believe it as fact... even thought it's really only based on "whisper down the alley"

All that said, you can NEVER go wrong with more HP on a boat. But with an 18-footer - yeah, 115HP is totally fine.

 

[bcahn19]

Count me as someone relying on online research prior to real-life experience. I apologize for not being clearer at the outset of the thread - I don't currently own but am interested in buying an older Sportsman 18'. One is available in my area and within my price range and in great shape, but has the 115hp 4 stoke. I've been in love with the hull design but nervous about power. Most online forums (and I've spent hours digging through everything) are very pessimistic about powering this boat model with a 115hp, but I also recognize for the model year the 115hp 4 stroke was more regularly outfitted for this boat than it is now.

Regardless, refreshing to get the insight in this forum. I understand what I'm getting into from a HP standpoint, and will reply back to this thread after purchase so that others after me can find a more useful resource if faced with this decision. In the meantime, I'm now focusing on Smart Tab installation! Thanks to all involved!

 

[DennisG01]

Good luck! Of course, a trial run (if available) would tell you everything you need to know

Just keep the Smart Tabs on the back burner for now. While there are plenty of benefits that it can provide in everyday use even with a light load (keeping the bow planted in choppy weather, for example) - wait till you get used to running/operating the boat for a bit.

 

[capeguy]

I had a 1999 Sportsman 180 with a 130HP 2 stroke. Was perfect combination. Friend had the same boat with the 150HP and it was too heavy, always had water in the boat as the scuppers were under. The 115HP will be just fine, but will lack the hole shot and acceleration. Unless you have a lot of weight in the boat you will be fine. Fantastic boat, wish I had never sold her...

 

[Capt Tom]

Yes! Absolutely! I have used them on my own boats, family and friends, and countless customer boats. They do EXACTLY as they advertise and they do it really well. Great bang for the buck! Inexpensive and only takes about an hour to install. Full hydraulic trim tabs are great - but those run $600 to $800 for parts and easily take (an experienced person) a solid half day to full day to install.

Dennis, great to hear your experiences with Smart Tabs. I thought these things were taboo on a Grady or similar type boat. Anyway, I installed these last year on my 205 Freedom with the F150. After a whole season running these they definitely do as advertised. As far as with or without, definitely with x 100.