Re: [AlbinVega] Gate Valve Removal Progress

[stevebirch2002]

Hi Chris

Best way I have found to remove the skin fittings and valves at one go is to use an angle-grinder on the outside and grind of the lipof the skin-fitting (carefully) then just push it upwards - piece of cake but be careful

Steve Birch

 

[chris20636]

Doh! Using the grinder approach would have been much easier than taking the furniture apart. (Now why didn't I think of that!!) Oh well, if I had known about this method before starting, I probably wouldn't have used it, since I was undecided about replacing the thru-hulls. Now that I'm certain to replace the thru-hulls, I might use the grinder/cutting approach to remove the last valve under the sink.

I haven't gotten to the shopping stage for replacements. I was not aware that there might be a problem locating replacements of the correct size. Thanks for pointing this out. IMHO, you would especially want to thru bolt the smaller ones, even more than the larger ones, since they are on smaller thru-hulls and therefore weaker. During the removal of my old gate valves, the only one the broke for me was the engine cooling thru-hull which was one of the smaller ones. Other than finding a source for the correct size, I don't see any alternative but to install larger ones as replacements. Since the new valves will have twist handles instead of large knobs stuck out the side, space shouldn't be a problem. It is just getting the courage to take hole saw to the side of the hull.

What about material? Have you decided what to go with, bronze? stainless? marelon? other? I am giving serious consideration to marelon, but I haven't made a final decision yet.

Good luck with your project.
Chris

 

[chris20636]

Rob,

I forgot to mention this in my last message. While browsing the boat books, I ran across "Sailboat Hull & Deck Repair" by Don Casey. I found an interesting suggestion in the section on thru-hull installation. Most of the material that I've read, suggest placing a plywood backer block that is shaped to the contour of the hull and sealed with epoxy, to distribute the load caused by the seacock. He suggests, as an alternative, that a backer block could be laminated from several layers of fiberglass material. This would take a little more time and effort, but the advantage is that the mounting screws could be replaced with studs that are fiberglassed into the backer block. This way you don't have to drill holes through the hull for the mounting screws. I like the idea of less holes in the hull. The down side, is if those studs get corroded or messed up somehow, it would be extremely painful to repair.

Just an idea,
Chris

 

[pelagicasd]

Another consideration for removing the thruhulls is to unscrew from the
outside. This presumes that you can get the valve off first. If you look at
the inside of the thruhull you will see a couple of small nubs. A tool
exists that fits in the inside of the fitting. Imagine a piece of pipe small
enough to slide into the smallest fitting. Now imagine another piece that
fits in the next largest fitting and so on up to the largest fitting. Now
telescope all of these pieces together with each piece sticking out of the
piece that it is inside of. This tool would be able to fit inside of all the
different sizes except that the little nubs on the inside would get in the
way. If grooves were cut into the tool it would slide in with the nubs in
the grooves. When you went to turn the tool the grooves would push on the
sides of the nubs and the thruull would rotate. WEST Marine used to carry
this tool but no longer does. Many boatyards have one and you might be able
to borrow or rent it. You wil have to hold the inside flange nut with a
wrench but the wrench won't have to move very much. If you can't get a
regular wrench on the nut try an adjustable packing gland wrench. If you
can't find one of these tools you might try looking for a piece of flat
stock the same width as the I.D. of the thruhull. Stick it in and use a
large wrench to try turning it. Using a heatgun to heat the thruhull can be
helpful also. Blow the hot air through the fitting not on the glass
surrounding it. When putting the new ones in use a sealant that isn't
considered permanent. I once put genoa track down with 5150 and when I had
to remove it later it took chunks of fiberglas with it. Good luck.
Walt, Lyric