Hi there, I'm getting ready to re bed my thru hull valves it seems the boat sat for some time with water surrounding the thru hulls inside the boat now I have rotted plywood, what's the chances of unscrewing the mushroom fitting at the hull outside ? I'd appreciate all techniques anyone has had luck with short of hacksaawing the old one off at the hull side! It tapping it around with a cold chisel?
Thre hull sea cock
- Thread starter hunter healer
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I used a Makita multi tool with a metal cutting blade. I cut the valve off the thru hull then made a toll to pull the thru hull out. Search on Don Casey thru hull removal for a diagram. This was not easy but I'm at the point of glassing in fiberglass backing blocks to mount the new thru hulls and valves.
There is a special through-hull tool that the boat yard uses to pull them. I just paid them to do it and saved myself all the frustration.
Rebedding was the best thing I did, especially for my sink drain and raw-water engine intake. I rebedded with starboard and 3M 4200 and kept the original valves. While waiting a week for a replacement battery, my bilge is dry as a bone...whereas I would always have SOME water in there after a few days.
Rebedding was the best thing I did, especially for my sink drain and raw-water engine intake. I rebedded with starboard and 3M 4200 and kept the original valves. While waiting a week for a replacement battery, my bilge is dry as a bone...whereas I would always have SOME water in there after a few days.
You can make your own thru hull tool with a piece of hardwood the right size to fit into the thru hull with a couple of grooves 180 degrees to each other. Some heat and either thin wire or fishing line to cut thru the existing bedding and the old thru hulls can be unscrewed (interior fittings and nut removed first) Have a look at Maine sails articles on how to build/install backing plates and use either proper adapters (Groco) to inline valves or proper sea cocks.
Word of warning though. Not all thruhulls will fit the Groco adapters. My Oem hunter ones did not. Had to order new ones.
Backing plate install here:
http://www.pbase.com/mainecruising/backing_blocks
Thru hull install here:
http://www.pbase.com/mainecruising/installing_a_thruhull
You will find tons of other helpful information on his site as well - worth the time for a look around!
Word of warning though. Not all thruhulls will fit the Groco adapters. My Oem hunter ones did not. Had to order new ones.
Backing plate install here:
http://www.pbase.com/mainecruising/backing_blocks
Thru hull install here:
http://www.pbase.com/mainecruising/installing_a_thruhull
You will find tons of other helpful information on his site as well - worth the time for a look around!
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