Adding a Third Log to a Pontoon

[sundeckbentley]

Hi, I am new to this forum. I am hoping I can get some help with a question on my 2004 Bentley 240 Cruise. It has a 90 HP Merc 2 Stroke.

I have heard many mixed messages about adding a third log to my pontoon boat. I want to add a log for more flotation as I am having a custom sun deck added to my Bentley.

I think if properly placed it won't interfere with the boats performance and will possibly enhance it. Can anyone help me out?

[DMAN1968]

You may want to try your question in the forum on The Pontoon and Deckboat Magazine website. Bound to get many more results. Good Luck.

[alan white]

It's probably not a good idea to add more weight to your boat than it was originally designed to float and add another pontoon to bring it back up.
Performance will not get better since you are adding a lot more drag-inducing wetted surface.
I'd think the best way would be to change to a longer and possibly wider pontoon boat that has what you want already, or at least can float more weight.
What you lose in staying with the shorter, smaller diameter pontoons is a bit of stability, as a central pontoon adds none. More importantly, it's a lot of work and money for little return, and your boat will be slower to accellerate and will use more fuel than a boat with two hulls of the proper diameter/length.

Alan

[marshmat]

I very much doubt you would see a performance improvement.

Although, we are talking a 24', 90hp pontoon boat, so "performance" is most definitely a relative term.

Adding a third pontoon will increase the load capacity, if the rest of the structure is strong enough to handle it. But it will not add much if any stability; more weight with the same stability makes for a rather cumbersome boat to handle. You will probably see a significant increase in fuel use and a decrease in speed. If you are just floating around at 6 knots it could be fine, but I think it would hurt performance when compared against trading in for a higher-capacity hull.

I think you'd be better off, both financially and performance wise, to go up a size if you really need the extra capacity. Perhaps a 26', or a 24' with wider (or more modern shaped) tubes. The value of the existing boat, plus the cost of the new tube, will probably be comparable to or greater than the cost of a slightly larger hull of similar design, age and quality.

[KCook]

Err ..............

http://boatdesign.net/forums/showthread.php?t=21641