Is it illegal to throw a larger hp motor than the boat's specs stamped on the plate?

Bob_VT

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

They are USCG Specs and iboats does not endorse any overpowering or overloading which would violate the USCG specification plate which is based on testing, hull length and beam.

The caveat is insurance. If you have an incident and are insured then you may be found liable automatically. Some states and the USCG do enforce the labels.
 

kfa4303

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

+1. While your boat may/may not be able to physically handle a larger motor, your insurance will not if it exceeds the manufacturer's recommendations.
 
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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

Got ya. Thanks. Wasn't planing on throwing a hydroplane turbine on it, but wouldn't mind a 135 or 150 from the worn out 115 that's on it. 33 with a load isn't actually a speed boat like I had in mind. 45-55 is more like it for me.
 

foodfisher

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

Showing my age here but the water gets awful hard above 35mph. Kinda hard on joints and bones.
 
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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

Showing my age here but the water gets awful hard above 35mph. Kinda hard on joints and bones.

haha, ya, I refuse to tube anymore, but I might try skiing again. Had enough tubin. Still fun to pull the younger ones.
 

JimS123

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

Legal or not, its just plain stoopid. If you have to go 45-55, buy a better boat. If you have an accident that's not your fault, better hope the other guy doesn't have a knowledeable lawyer, or he's stoopid too. If you run into me, I'll own your firstborn.
 

matt167

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

I would think the boat in your sig should run 40 MPH or so with it's rated max hp running correctly and with the boat in good condition and correctly propped. Mercury 1150 TOP should get there if everythings in check, but even a 'rude 115 should have the ability.
 
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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

So..... I might have missed it but what's the HP rating of your boat anyway?

Also, what engine model do you have, and do you know the rpms it turns at full throttle and a light load in the boat? When the boats on plane where is the AV plate in relation to the water surface?

Where all this questioning is leading is that you might not have the optimum prop, and might possibly be able to gain some performance with a different prop, or possibly changing engine height.
 

ondarvr

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

Some states and the USCG do enforce the labels.



The USCG does not enforce any HP regulations, they can site you for reckless operation of the boat though, or if things look out of control or dangerous they may send you back to the launch. Some states do have laws in place. Insurance companies vary on how they handle it, if they are told a head of time they may set the rate for the added risk (I asked mine about it).

After saying that, it's not a good idea.
 
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Home Cookin'

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

ondvr has it right.
Law: Whether something is "illegal" is a matter of the applicable local law--some laws incorporate the plate as a standard, some don't. Laws are statutory (written in the code) or common (established by controlling precedent from a reported case). You have to point to a specific statute or controlling case in YOUR jurisdiction, not someone else's, to find if going over the plate is "negligence per se" or in layman's terms, automatically negligent. "Illegal" is not a matter of opinion.

Insurance: Whether your insurance is at risk is a matter of YOUR contract (policy) and no one else's. No one here can say what you do will affect your coverage unless he has first read your policy. But note that many policies say there is no coverage if the loss/claim occurs as a result of an illegal act--so you have to look to applicable local law in YOUR jurisdiction

If there is no controlling statute, case or insurance contract term:
Then the issue is whether your conduct (yours, not someone else's) is negligent or unsafe. That depends on the circumstances at the time. Hobbyists overpower small boats all the time and race them. They can buy insurance for it. They can operate safely. No problem For ordinary use, if you are "over powered" and get in an accident at idle speed, the fact that you are over powered will not matter. If you get in a wreck at speed, being overpowered might be evidence of negligence, might not, and only pertains to YOUR facts, not someone else's.

Practical: Obviously you avoid the whole issue by staying within the plate--like avoiding a DUI by not drinking at all, rather than arguing about your number of drinks/time/your weight. Also there is the overall law that you can't operate a boat unsafely (recklessly) and that starts as a matter of the judgment of the guy writing the ticket--a rather soft standard.

This should be a sticky!
 

ezmobee

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

I wouldn't hang a 150 on it as that's typically getting into V6 territory. If I were to happen upon a 140 V4 though........... ;)
 

seahorse5

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

Check your state's boating laws, some specifically say not to overpower a boat according to the Coast Guard sticker maximum hp rating.
 

Frank Acampora

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

At 33 MPH, yes, you engine is not performing correctly but those V$ engines are workhorses AND can be modified. You can get a "bubble back and tuned exhaust from a larger HP V4 and it probably will fit in addition to giving more pep to the engine.

Now, You have a computer and it has a graphics app. I can't tell you what to do, but if your current capacity plate were illegible, you could make a replacement. If you were to fudge the numbers a bit, that's on you. Mind you, I never said it and Iboats forums would strongly object to recommending an illegal act like this.
 
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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

I would think the boat in your sig should run 40 MPH or so with it's rated max hp running correctly and with the boat in good condition and correctly propped. Mercury 1150 TOP should get there if everythings in check, but even a 'rude 115 should have the ability.
About 33 with a couple of people and full tanks. Engine is old. 73, and I was told 115 isn't measured at the prop back then. No power trim, just power tilt. Have to do it manually. Did it all the way with the 5 holes, and couldn't turn without cavitating, so went back one hole, and I guess that's all I can tweak this one. Just ordered a 13 1/4 19 pitch to replace the lightly damaged 13 1/4 17 pitch currently on it that gets 5300 rpm. Manual says 4,500 to 5,500 with the full 115 at 5,000, so I thought I'd drop a few hundred rpm, and see it the new prop and pitch will get me close to 40. I know my old glastron with a 135 did 45 easy. Little heavier boat as well, thus rated for 140 hp, I guess is how they rate them.
 

xjdriver

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

As long as the compression is good you should still be getting around full hp. Dropping rpm and lugging motor probably isnt the best idea, that rig should do more than 33 somethin aint right.
 

matt167

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

About 33 with a couple of people and full tanks. Engine is old. 73, and I was told 115 isn't measured at the prop back then. No power trim, just power tilt. Have to do it manually. Did it all the way with the 5 holes, and couldn't turn without cavitating, so went back one hole, and I guess that's all I can tweak this one. Just ordered a 13 1/4 19 pitch to replace the lightly damaged 13 1/4 17 pitch currently on it that gets 5300 rpm. Manual says 4,500 to 5,500 with the full 115 at 5,000, so I thought I'd drop a few hundred rpm, and see it the new prop and pitch will get me close to 40. I know my old glastron with a 135 did 45 easy. Little heavier boat as well, thus rated for 140 hp, I guess is how they rate them.

Right the old '73 is not prop rated. You could go to a newer motor from the mid 80's onward and probably get 130hp with the same rating system as the '73 but still be an actual 115hp outboard... 200 RPM really isn't far off so it's doubtful that a smaller prop will help. possibly it isn't running 100%. It won't get much faster unless you replace likely waterlogged foam.
 
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Joined
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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

I'm gonna run to autozone, and check out how much for a compression tester, and check it, grab 4 new sparkies, and some sea foam. As for the rpm, the manual says it produces it's 115 at 5,000 rpm, not 5,300 where I'm at now, so I thought moving up a prop pitch to the 19 from the 17 "slightly damaged one", would get me to the magic 5,000 number.
 

Alwhite00

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

Did I miss it? What is the boat rated for?

LK
 

ondarvr

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Re: Is it illegal to throw a larger hp motor than the boat's specs stamped on the pla

I'm gonna run to autozone, and check out how much for a compression tester, and check it, grab 4 new sparkies, and some sea foam. As for the rpm, the manual says it produces it's 115 at 5,000 rpm, not 5,300 where I'm at now, so I thought moving up a prop pitch to the 19 from the 17 "slightly damaged one", would get me to the magic 5,000 number.

You are better off at 5300 than 5000.
 
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