should a boat flex?

[bandit86]

we went out last weekend on my 25ft 87 bayliner 2455, 5.7omc. when standing in the cabin, about the middle of the boat, it seemed to me the floor was flexing a bit as the bow was going over waves... is this normal?

 

[Reel Poor]

Re: should a boat flex?

Thats typical of an older boat that is starting to show signs of fatigue and possible stringer problems. It's definantly not a design feature.

If you stand in the doorway of the cabin and can feel air pressure changes when the boat hits a wave that is also a bad sign.

 

[Bondo]

Re: should a boat flex?

should a boat flex?

No.............

 

[mattttt25]

Re: should a boat flex?

i think all boats flex to some degree. there could be nothing wrong with your hull or stringers, and simply your deck plate in that area has taken some water and is flexing. i would walk around the boat at rest and see where you have flexing. you may need to replace some of the deck, and also address the issue of water getting to these areas.

 

[Texasmark]

Re: should a boat flex?

I'll take the no on flexing and agree on the stringer weakness.

I was only in one boat with severe stringer damage and it was a guide/boat I rented in N.E. Florida. The flexing of the floor was severe as we rode the waves. Several times I thought of telling the guide to turn around and go home. We were fishing marshes and land was close by was the only reason I didn't.

The other boat where I experienced damage was an MFG boat I was testing to purchase; about 16' with an early Johnny V4 85 hp. The interface of the deck to the hull was cracked and must have had stringer problems too because you could look at the interface and watch the deck move up and down.

Needless to say I carefully took it back to the owner.

Mark

 

[Stratocaster]

Re: should a boat flex?

Do you see any stress cracks at the obvious pivot points on the hull? If so, then the answer is definitely "no", the hull should not flex. Stringers and hull-to-deck joints are where I would look for failure severe enough to cause the boat to bend.

Now if you are just talking about the floor where you were standing "feeling like" it was flexing, well, that's not as serious. You could just have some water intrusion, causing the plywood core to go soft. That happens to quite a few boats, and the fix is not that bad. Or you could just live with it.

 

[JasonJ]

Re: should a boat flex?

This really depends on how the boat was built. If it used 1/2 inch ply and that ply is bridging a stringer gap greater than 15 inches, you will feel some flex. If you have never had this flex occur before and it is hapening now, than the floor could be degrading. If you have never stood in this spot before while underway on rough water then you don't have much to compare with. How much do you weigh? Is there other areas on the floor that flex? What exactly is a "bit" of flex?