I have used a pillow and a broomstick to plug
the hole left when a 3" propshaft broke at the coupling and the entire shaft slid out of the boat. Initially we were taking on an easy 100-gals a minute, but once plugged we where at about a pint a minute. This was on a 125-ft crewboat, and once the hole was plugged we still off loaded the cargo and ran the 50-miles back to base in the Gulf of Mexico
I have used sawdust taken underwater in a plastic bag and released into leaking planking on wooden boats after they have gone back in the water
from a dry docking
The sawdust is sucked into the leaking planking and swells in place. It takes about 5-minutes to stop +95% of the leak.
I have used 8-oz Sail Repair Tape on the bottom of inflatable
dingys to seal holes. It lasted over 2-years before we got around to putting on a proper Avon
repair patch. I think it would work very well as an emergency
"bandaid" on a hull
fracture/crack or even a smallish hole and stop the water
inflow on a wood, fiberglass
hull until you could make up a fabric/5200 patch. NOTE: You have to put the patch on from the outside of the hole where the water pressure will help press the fabric
into the damaged area. It won't hold if applied inside the boat - the water pressure will blow it off. Sail tape is very tough and flexible.
I've never tried it, but I would think that you could use the foam rubber out of your cushions/mattress and shove it in the crack/small hole from the inside to slow the flow of water down.
All you are trying to do is slow down/reduce the massive inflow of water so you can buy enough time to make a more permanent repair.
We had a "mast head
in the water" knockdown once far offshore
and had lots of water come in - 300+ gallons. The cockpit
was brim full as were the cockpit
lockers from the water entering the cockpit lids joints.
First thing I did was start the engine
while we still could to provide power to the batteries, then turned on both Rule
3600 pumps (each rated at 60-gpm) and all the interior
lights, then had the wife start pumping with the below deck
Whale Titan 1.5" pump. I was able to look around for other damage and luckily we had no hull/rudder damage. It took about 5 to 10-minutes to get all the water out.
Big pumps are always a very important thing to have during these scary times!