removing the top plugs on your toons

[toondog]

Found this post searching for info.

A lot of them here do have a schrader valve in them on the top some place . With a drain plug on the top, near the back . This has a pipe in it that goes down to the bottom of the log. So any water in the log blows out when you put air in it.
Im with GregH here for sure . Had a friend put a air compressor on his to check it out. Poped open a seam at the bow with about just 5 lb psi. If you go that way try a air hand pump.
Dont forget there always is good old 3M 5200

I'm sure it really depends on the thickness of the aluminum though. It seem some manufactures sell toons with 3.5lb of pressure in there toobs . On a really hot day sitting out of the water, that would have to push the pressure well past 5lb psi.


2009 Berkshire Pontoon Boats 201FC Standard Features
Colors Choices
• Cabernet
• Forest Green
• Graphite
• Navy Blue
Standard Features
• 3 Year Stem to Stern Warranty
• Limited Lifetime Chassis Warranty
• Limited Lifetime Deck Component Warranty
• 3.5 psi Air Pressurized & Chambered Pontoons
• Full Length Protective Bottom Keel
• Boca Raton Carpet
• Tachometer
• Voltmeter
• Fuel Gauge

[dahogman]

Added pressure does not make for added bouyancy. If pressure made for extra bouyancy Scuba divers would bounce around on top of the water like bobbers. Pull the plugs and check em.

[wed]

OK. say I pull the plug and there was pressure in the toon.... pressure inside and outside will be the same as long as the toon is open. I put the plug back in and put it in the water, it will cool off which will cause the pressure to drop inside the toon. Now the pressure will be lower than the pressure outside. The pontoons go on vacuum. This is exactly what Herb was talking about. The bottom line is that unless the toon is vented you cannot guarantee what the differential pressure between inside and outside will be. The differential pressure is the problem.

Which is worse, pressure of vacuum? The problem with going on a vacuum is that if there is a leak and it is exposed to water the water will be drawn into the toon. It would be reasonable to leave a slight positive pressure in a unvented toon because of this.

[WaltF]

Hey now.... Good discussion!

Ya, what made me think more about this, besides trying to figure out if there is any water in there, was the PSI in there up here in Colorado.
Ive heard over the years everyone stressing to NEVER put more then a couple PSI into the toons.
Yet simple math tells me that if my toon was sealed at sea level, then shipped up here to Colorado, there is MORE then a couple PSI in there. Infact, I figure there is atleast 5 PSI in there while i tow it over a pass up here.
So they obviously can handle 5 PSI.
How much they can handle, im not sure.

Still trying to decide if i should open em to check em.
Too dern cold to mess with it right now though...

[toondog]

I put the plug back in and put it in the water, it will cool off which will cause the pressure to drop inside the toon. Now the pressure will be lower than the pressure outside. The pontoons go on vacuum.

That's why I always suggest (if you want a little pressure) to seal them up at night after everything has cooled down. Winter seem like a prefect time to do this, night or day.

[dockholiday]

Just remember psi and psig are not the same animals. Normally, from what I remember, equations use psig.

http://cr4.globalspec.com/thread/31986

found this but am sure there is a lot more out there.
doc

[dahogman]

I'm gittin a headache wit al dis thinkin!!!

[WaltF]

Beer is gonna have to be included to fully understand the equation.

[toondog]

It's important to note that only at the so called "standard" atmospheric pressure or 1 bar or 14.6959 psi or 29.92" Hg is PSIA = PSIG + 14.6959 psi. Change the barometric pressure due to weather variations, change altitude where the pressure gauge is located or place the gauge in some environment isolated from atmospheric pressure and the 14.6959 constant is no longer valid.

Y'all do understand this...don't you?

[WaltF]

Ya.. i just want to open the plugs on my toon. I dont really want a PHD in liquid dynamics.....

[dockholiday]

I got an idea...........why don't you just open the plugs and tell us what happens...........I say nothing will happen
doc

[JohnO]

It's important to note that only at the so called "standard" atmospheric pressure or 1 bar or 14.6959 psi or 29.92" Hg is PSIA = PSIG + 14.6959 psi. Change the barometric pressure due to weather variations, change altitude where the pressure gauge is located or place the gauge in some environment isolated from atmospheric pressure and the 14.6959 constant is no longer valid.

Y'all do understand this...don't you?

Yep. But then I'm an engineer and we are kind of twisted that way.

[WaltF]

Im prob going with the doc on this one....
I like the idea of lowering a fishing line and weight in there to check for water too!
I'll let you all know what happens!

[toondog]

I'll let you all know what happens!

[WaltF]

Damn! Maybe NOT!