Pontoon Boat & Deck Boat Forum

My 1988 Party Hut's transom has a purpose built hole in the rear bottom to allow water in and out, and the transom "flooded."

What's the purpose of this - to provide damping/sound reduction for the motor? It seem counter intuitive since that section - if sealed off - would provide about another 150 lbs. of buoyancy, not to mention keep the plywood the motor is mounted to out of the water.

Yep, this stuff does indeed keep me up at night!

Same way!

ditto on mine!

I think because of splash you would be filling it up, but I was think about sealing that hole up too but I don't think you gain that much in floatation

I have no idea why mine is like that either, but here's my guess...

When they designed the transom, and how it would affix to the boat, the best engineered drawing resulted in the V pattern seen on almost all pontoons. Well, if you leave the bottom of the V sealed, it fills with water, so the hole is needed. As a closed device, no significant buoyancy added. While open, gives a protected place for wires/fuel line to run/lay as they go from boat to motor.

For me.... it's where I toss my plastic wheel chucks when moving the trailer! They get the caked-on mud, spiders, ants, and other crap, washed off while being stored where they are readily available. It is also going to be where I place my strainer/water intake piping for my wash down/live well fill pump!

RonKMiller wrote:What's the purpose of this

<BS>
Well, if you follow bernoilli's third principle, the open rear of your transom creates a "hydro-vacuum", which in turn generates a negative pressure wave inside the transom, causing an INCREASE in air pressure around your motor, essentially acting like a supercharger, then closing the loop via the boats exhaust system. This phenomenon, known by boat designers as a "suckercharger", was developed during world war two, and was a top-secret feature of the (of course, top secret) assault pontoons, which were air-dropped into the Bodensee in Switzerland, to assassinate vacationing SS and Wehrmacht officers. The technology was so successful, that nobody survived to tell about them.
</BS>

Beats me...
But the Admiral thinks it's the ladies loo...

BobG wrote:

RonKMiller wrote:What's the purpose of this

<BS>
Well, if you follow bernoilli's third principle, the open rear of your transom creates a "hydro-vacuum", which in turn generates a negative pressure wave inside the transom, causing an INCREASE in air pressure around your motor, essentially acting like a supercharger, then closing the loop via the boats exhaust system. This phenomenon, known by boat designers as a "suckercharger", was developed during world war two, and was a top-secret feature of the (of course, top secret) assault pontoons, which were air-dropped into the Bodensee in Switzerland, to assassinate vacationing SS and Wehrmacht officers. The technology was so successful, that nobody survived to tell about them.
</BS>

Beats me...

<bs>WOW... now I'm impressed... the vast empire of your knowledge astounds my mere human brain.....</bs>

I think it's a simple as needing to get to the motor mount nuts in order to install the outboard on the transom of the pod. In order to assure that water wouldn't get in the pod from the top you would have to seal it some how. If you did that you can't easily access the mounting bolts. Mine has the fuel tank mounted in it. When I'm underway the water drains out the hole but at idle it'll fill up.

I was always wondering about that also.
My friend has a Tracker which also has the fuel pod built inside the transom. I get the idea of having access to the motor mounting bolts. But I wonder why creating a fuel tank for that space wouldn't be the norm nowadays. Seems like a good idea.

evinrude2stroke wrote:I was always wondering about that also.
But I wonder why creating a fuel tank for that space wouldn't be the norm nowadays. Seems like a good idea.

Yep, would save a bit of valuable space elsewhere for speakers...

GXPWeasel wrote:

evinrude2stroke wrote:I was always wondering about that also.
But I wonder why creating a fuel tank for that space wouldn't be the norm nowadays. Seems like a good idea.

Yep, would save a bit of valuable space elsewhere for speakers...

OR.... a keg-orator

PlaynDoc wrote:OR.... a keg-orator

I think the constant vibration of the transom would make it a foam-er-ator!

evinrude2stroke wrote:I was always wondering about that also.
My friend has a Tracker which also has the fuel pod built inside the transom. I get the idea of having access to the motor mounting bolts. But I wonder why creating a fuel tank for that space wouldn't be the norm nowadays. Seems like a good idea.

Isn't it At least all the higher end toons all have transom mounted tanks...

Have I stumped the EXPURTS on this one?

It just doesn't make ANY sense, although I bet it keeps the sound/vibration levels way down.

Yep, that's got to be it.

Either that or it's some sort of OBAMA plot.

My guess is for one, cheaper or cheapest design to manufacture. Two eliminates any need for a bilge pump to keep water evacuated. Three it eliminates the worry of water freezing up and breaking things over winter storage. Four it does away with accumulated stale stinky mosquito infested water in ones transom.

I could probably come up with some more.. Anyway under power your transom drains out or evacuates to empty through the drain hole. I actually increased the diameter of mine some so it will actually drain faster.. So I'm not thinking the accumulated water theory is in reality "holding any decibels"