my son just bought a new pontoon boat, he upgraded the motor and now the boat dips at the back is this ok?

Answer 1

ya talking about a pontoon boat. these boats are not the most, hydrodynamically designed craft. they are designed to run on calm water, at slow speeds. 'upgrading' an engine is kinda pointless, unless it was seriously underpowered to begin with.

a lot of boats will 'dip' due to the weight of the motor. or seem to sit a little stern heavy. this is fine. (yes race boats do sit low in the rear, but, they are designed to go fast, not sit still)

if its dipping when you put the power down, this is probably due to just too much hp for the sponsons to cope with. pontoon boats are not, tecnically, planning craft. it is possible to plane them, but, the sponson design is not a high speed design. because of this, they will dig and encounter large resistance before overcomming, more than that of a planning Catamaran hull. this will cause the boat to sag, as it falls into its bow wave and attempts to overcome it. if it never does overcome it, you have reached maximum velocity for that boat and your wasting power and the engine is rendered useless beyond that point.

so if its just sitting a little low in the rear at rest, but nt to the point where the rear of the sponsons are under water or just about. wouldnt worry too much about it, shift the beer cooler forward and throw in an extra 6 pack.. if its sitting very low. you have over powered the boat, and my advice would be to sell the 'upgrade' and get a 'downgrade'

and if its dipping when under way, again, downgrade and if he wants to go fast, buy a monohull or catamaran.

Answer 2

If the new motor is larger, and it's an outboard, then it's likely that
he's added too much weight to the stern - causing the "dip".
Ballast in the bow would adjust that, but be wary of adding too much weight... best case, that will lose the advantage of the extra power... worst case, you could sink :-)

Or maybe you're referring to a dip when he accelerates.. in other words, you open the throttle and the stern of the boat "digs in"... that would be a problem with the trim, or the adjustment of the motor position - the larger motor's stem may be too long, putting the prop too far down, for instance.

It's also possible just to put too much power on a given size of boat, which will give you all kinds of handling problems.

Answer 3

No. If the motor is too heavy and keeps the boat off balance, it is likely that the boat will not have the stability to handle rough water. Especially if the boat's motor is too powerful, the boat can be capsized easily.

Answer 4

There should be a placard somewhere on the boat that lists maximum size of outboard allowed.
It is not OK if the maximum is exceeded.
If the size of the motor is allowed, is the amount of "dip" small or great?
A small amount is OK and can be balanced out with weight forward.
A large amount is not good and can affect safety and handling.

Answer 5

i take it you mean it,s riding low,,this is common on most pontoon boats,,until they take off,,then they plane out,,if it don't plane out in a few second,s this could become dangerous,,the weight issue may be a factor on this boat too,,i own one,,and when everyone is at the back,,it rides a little low,,i sort of have to remind people that the weight need,s to balanced out,for it to be safe,,but it can be a safety issue if you get caught in a cross wave from a bigger boat,,they can flip over,,or in my case mine flipped strait up in the air,,it didn't take everybody long to get to the front of the boat after that,,but i will admit,,it scared me,,and i was driving,,and the water came up and touched my feet,,so be care full and try and follow the boats engine size limit,,then it should be OK,,i hope this help,s you.

Answer 6

There's a metal plate at the rear of the boat with the maximum rated h.p. If the motor is over that then it's in violation of a bunch of laws ( Coast Guard- local - state ect.)

Answer 7

If the dip is while sittin' still it might be ok, i would try goin out and seein' if u can plane off and see if the dip is better, but be careful, it is a unsafe if the dip is severe, i would advise moving back to a smaller motor.

Answer 8

My grandfather had a pontoon boat when I was growing up. I always enjoyed it. You can still ski and tube on the back. And they are good for partying and for the family. So yes I would say it was worth buying.

Answer 9

well yeah. you said that he upgraded the motor. so once you reach about 2500 RPM the boat will start to dip. my grandmas does the same thing. but we usually dont go any more than 2000 RPM anyway. slow rides are better for my new baby cousin charle.

Answer 10

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