Question on overpowering a 16'5 boat by 10 HP

[stjernefodt]

Hello all, long time lurker here.

I have a Lowe 1677WT that I'm wishing to repower. Its max rating is 50 HP, while the max weight rating for the motor is at 346 lbs. I was looking at a 50 HP 4-Stroke Yamaha which weighs 237 lbs, but since the 60 HP version weighs the same, would it hurt to choose the 60 over the 50?

I'm not worried about liability issues, just safety and handling of the boat, and would I loose some mpg? Also, my boat has a sister model with a center console (mine's a tiller) that's rated for 70 HP, so I'm convincing myself that those 10 hp wouldn't affect it much.

Any opinions on this?

 

[tashasdaddy]

Re: Question on overpowering a 16'5 boat by 10 HP

that is total up to you. i never say to put more power on a boat than it is rated for. this does not mean i would not do it to my own boat.

 

[Home Cookin']

Re: Question on overpowering a 16'5 boat by 10 HP

the issues with going over the capacity are:
1. weight--you answered this
2. safety--10 hp shouldn't make that much difference as long as you are the only driver and keep it in mind--and are skilled enough to know
3. voiding liability insurance (and possible ticket for improper equipment)--you say you don't care; our advice is that you should.

there's a reason you get higher rating with a console than a tiller: control and weight distribution.
Now, of course the bigger engine will get worse mpg. And if you swear you will operate it safely, you won't be going up to the last 10 hp anyway. So why bother, and why spend the extra?

 

[JustJason]

Re: Question on overpowering a 16'5 boat by 10 HP

60HP and a tiller????

Hope you have big arms.

 

[tx1961whaler]

Re: Question on overpowering a 16'5 boat by 10 HP

Hello all, long time lurker here.

I have a Lowe 1677WT that I'm wishing to repower. Its max rating is 50 HP, while the max weight rating for the motor is at 346 lbs. I was looking at a 50 HP 4-Stroke Yamaha which weighs 237 lbs, but since the 60 HP version weighs the same, would it hurt to choose the 60 over the 50?

I'm not worried about liability issues, just safety and handling of the boat, and would I loose some mpg? Also, my boat has a sister model with a center console (mine's a tiller) that's rated for 70 HP, so I'm convincing myself that those 10 hp wouldn't affect it much.

Any opinions on this?

That's the common misconception that runs around on these overpowering threads, that the weight of the outboard is the primary concern. Stern level/freeboard concerns aside, most transoms could easily handle a static weight of 4 or 500 lbs easily. It's the torque that the propeller thrust exerts on the transom that's the issue. When operating, the motor is trying its hardest to twist the transom off of the boat using a 20-25" lever arm. More HP equals more force at the end of the lever. Too much force and the transom breaks.

 

[smokeonthewater]

Re: Question on overpowering a 16'5 boat by 10 HP

ALSO.... just because the "sister boat has a console does NOT mean that there is no other difference such as a beefier transom or more bracing

 

[ondarvr]

Re: Question on overpowering a 16'5 boat by 10 HP

Identical boats will have different ratings for tiller and remote controls even with no structural differences.

60 isn't big for tiller, just not as common in some parts of the country.

You will get about the same MPH with either motor.

Performance may be slightly better with the 60, but it won't be a huge difference.

Its up to you on which one to get.

My insurance company only asks the HP of the motor and hands me the papers to sign with no other questions. Its 50hp over the hull rating.

 

[stjernefodt]

Re: Question on overpowering a 16'5 boat by 10 HP

I think I'll stick with the 50 HP, since the increase in speed will be minimal and I'll save those extra $500 on the prop and rigging.

Thanks everyone.

 

[trendsetter240]

Re: Question on overpowering a 16'5 boat by 10 HP

My insurance company only asks the HP of the motor and hands me the papers to sign with no other questions. Its 50hp over the hull rating.

My insurance was super easy to get aswell. Hardly a question about the boat, didn't even ask me what HP or size just approximate value. Besides mine doesn't even have a rating plate!

When you have a claim, they will go over that boat with a fine toothed comb. It is the insurance adjusters job to find any reason they can not to pay. Ask me how I know this...


But to each his own..I'm with TD on this..I'd never advise someone to do this but that doesn't mean I wouldn't do it myself.

Cheers~!