Removing de-zinc-ed brass through hull tailpiece

[jlp0217]

Anyone got any good ideas for removing the remains of a de-zinced tailpiece from a ball valve without destroying the ball valve's threads? Everytime I try to remove a hose a hose from a through hull, the tailpiece just breaks off, rather than the hose coming off. But this one when I took a wrench to the remains, the hex part of the tailpiece just crumbled. I'm always careful to make sure I get bronze replacement tailpieces, but I haven't replaced all of the old ones yet.

 

[ggrizzard]

Had the same problem this week with raw water intake. I discovered that the tail piece (nipple) installed 25 years ago was made of brass and crumbling. The valve and tru-hull were bronze. Due to age of thru-hull, valve and nipple, I just cut the whole assembly and replaced with all bronze... Cheap insurance.

 

[njlarry]

Might be faster easier and safer to replace it all. If the tail piece is gone how much better is the valve and thru hull.

 

[Ron20324]

Use a pipe wrench- not vise grips.

 

[jlp0217]

Use a pipe wrench- not vise grips.

The vise grips were to keep the ball valve from turning while trying to remove the nipple. Would replace all if the boat wasn't in the water.

 

[njlarry]

Yes, replacing complete thru-hulls while in the water is not a good idea.
BTW, handsome looking pooch.

 

[kerryedwards]

In these circumstance I would typically take a small hacksaw blade and make some cuts into the tailpiece inside the ball valve trying to not go so deep as to damage the threads in the ball valve. Maybe three or four cuts. I'd then take a small chisel between the ball valve and remains of the tailpiece and see if I could break it into pieces. Given the state of the tailpiece a chisel might work without the cuts. There are tools designed to remove pipes which grip internally but I don't think the remains of the tailpiece would be strong enough for one to work.

 

[agprice22]

It seems you need to get to the piece that is on the inside (the male part threaded down into the female part)? If so, create a screw driver with steel bar that will impact the insides of the nipple. Taper it gradually, and sharpen the edges, so you can tap it in til it locks up. Then back that nipple out. Some stock weldsteel bar 1/8" thick by 1" or so wide can be cut with a metal saw, ground into a taper, have an edge put on it, and gently driven into the inside of the nipple and used to back it out. Basically, you are creating a knife/screwdriver.