Does your Toon “leak”?

BillTex · 05-18-2025, 07:18 AM

Just launched this week, and every year I think about this: after launching there is some air that escapes from the pontoons. This usually continues for several minutes until the boat settles. I can hear and see air bubbles as escaping the pontoons. The boats sits level and is not low in the water. When I pull the boat in the fall I have never seen any water leak out. I always assumed this is normal and it probably due to pressure differential.
Does your toon do the same?

Thx, Bill

TiltonBB · 05-18-2025, 08:01 AM

Where do you see the air and bubbles coming from? If it is on the top, might not be not a problem. If it is on the bottom it could be a problem. I have had pontoon boats and don't remember any air escaping when they were launched.

BillTex · 05-18-2025, 11:17 AM

The bubbles come from beneath the waterline (obviously) or I could not see/hear them. AFAIK they are near the weld lines. I sealed all the welds with flex-seal but I could still hear some “bubbles” when i launched this week. It only goes on for a few minutes, so if there is a “leak” it likely is not letting much in.
Considering how these toons are built, I am guessing this is fairly common, but not everyone is as anal as I (engineer…).

Again, when I pulled the boat last fall, there was no sign of any water leaking back out, no sloshing, and the boat was not unreasonably heavy to winch on the trailer. I am thinking it may be the pressure differential forcing out some air when the toons are partially submerged (Boyle’s law).

I’ll throw this out to the crowd: when you launch this year, if it is a quiet area, pay attention and see if you can hear/see any bubbles.

Thx, Bill

TiltonBB · 05-18-2025, 11:46 AM

Many years ago I had an older pontoon boat that leaked. I made up a fitting that went into the drain plug and put about 3 pounds of air in them. It was easy to find the leaks with a soapy water spray. I marked them and took it to a welder. If you try it I wouldn't put much more than 3 or 4 pounds of air in them. The results could get ugly.

codeman671 · 05-19-2025, 09:11 AM

I had one a while back that had a leak. When we pulled it out of the water you could hear the sloshing inside the tube. It did have a list to it in the slip. It was under warranty and was taken care of.

05-18-2025, 07:18 AM	#1
BillTex Member Join Date: May 2024 Posts: 40 Thanks: 2 Thanked 9 Times in 9 Posts	Does your Toon “leak”? Just launched this week, and every year I think about this: after launching there is some air that escapes from the pontoons. This usually continues for several minutes until the boat settles. I can hear and see air bubbles as escaping the pontoons. The boats sits level and is not low in the water. When I pull the boat in the fall I have never seen any water leak out. I always assumed this is normal and it probably due to pressure differential. Does your toon do the same? Thx, Bill

05-18-2025, 08:01 AM	#2
TiltonBB Senior Member Join Date: Feb 2005 Location: Gilford, NH and Florida Posts: 3,008 Thanks: 699 Thanked 2,203 Times in 937 Posts	Where do you see the air and bubbles coming from? If it is on the top, might not be not a problem. If it is on the bottom it could be a problem. I have had pontoon boats and don't remember any air escaping when they were launched.

05-18-2025, 11:17 AM	#3
BillTex Member Join Date: May 2024 Posts: 40 Thanks: 2 Thanked 9 Times in 9 Posts	The bubbles come from beneath the waterline (obviously) or I could not see/hear them. AFAIK they are near the weld lines. I sealed all the welds with flex-seal but I could still hear some “bubbles” when i launched this week. It only goes on for a few minutes, so if there is a “leak” it likely is not letting much in. Considering how these toons are built, I am guessing this is fairly common, but not everyone is as anal as I (engineer…). Again, when I pulled the boat last fall, there was no sign of any water leaking back out, no sloshing, and the boat was not unreasonably heavy to winch on the trailer. I am thinking it may be the pressure differential forcing out some air when the toons are partially submerged (Boyle’s law). I’ll throw this out to the crowd: when you launch this year, if it is a quiet area, pay attention and see if you can hear/see any bubbles. Thx, Bill

05-18-2025, 11:46 AM	#4
TiltonBB Senior Member Join Date: Feb 2005 Location: Gilford, NH and Florida Posts: 3,008 Thanks: 699 Thanked 2,203 Times in 937 Posts	Many years ago I had an older pontoon boat that leaked. I made up a fitting that went into the drain plug and put about 3 pounds of air in them. It was easy to find the leaks with a soapy water spray. I marked them and took it to a welder. If you try it I wouldn't put much more than 3 or 4 pounds of air in them. The results could get ugly.

05-19-2025, 09:11 AM	#5
codeman671 Senior Member Join Date: Jan 2005 Posts: 3,496 Thanks: 221 Thanked 812 Times in 488 Posts	I had one a while back that had a leak. When we pulled it out of the water you could hear the sloshing inside the tube. It did have a list to it in the slip. It was under warranty and was taken care of.