Thru-Hulls

[Mo]

Thru Hulls

Guys,
I've watched guys breaking themselves up trying to get into small spaces and to remove thru hulls. Just a quick note: I used a dremel tool with a diamond cut blade on it. Shove the end into the thru hull from the outside about 1/2 inch to 3/4 inch depending on fiberglass thickness... and zip a cut all around. One smack of a hammer will put one piece on the ground and the other inside the boat.

When I was overhauling the boat in 2007 I was fighting like a animal and pulled muscles in my ribs to get one off and had to figure out a way to cut it. I asked myself...what can I get in there to cut that SOB off. Have since shown or done it for others. Less than 5 minutes that hole is open! It is a good idea as well to mix some epoxy with glass fiber and rub it around the exposed fiberglass in the hole with your finger as well...just to permanently seal the fiberglass. Let that dry before installing new thru hull.

That will save allot of sweat and swearing.

[Skywalker]

I had pipe glassed into my Tartan 27 and gate valves threaded on. Yup, original factory. Everything else on her was nicely done. Go figure. I replaced the head intake and discharge with bronze. Heavy and expensive. I have subsequently replaced everything else with Marelon and I'm happy so far.

Marelon appears to resist sticking better.

[Bold Rascal]

Nice install 67

+1 on the Marelon, Also it was the only 1/2" NPS seacock I was able to find.

Had I known better at the time. I would have taken out the 1/2" and up sized to 3/4' but it's performing well at present as it is.

[jbsoukup]

my C30 had glassed in pipe nipples. I used a hole saw just large enough to get on the outside of them. Drilled from the underside of the boat - easy peasy
I then cut the inside "volcano of resin" square to the new thru hull leaving enough to make a nice landing for the big washer.
bedded the flanges on the outside in 5200

[Cool Beans]

I replaced the last of the 38 year old glassed bronze nipples with bonafide seacocks this spring. With all the stories I've heard and warnings presented to me. . .they were all in perfect condition with no signs of pink under the blue/green layer. No leaks, no deterioration, and they PO had even put new ball valves on them.

Of course, I never would have been able to tell how well they were with out getting them out. . .which I guess is part of the point of replacing them

[2dogsnight]

plugging thru hull

Took motor and shaft out of the boat...would like to plug the thru hull - temporarily.....thinking of epoxy in a wooden plug.....can be drilled out when is time to install shaft again......?????...better ideas??

[romantic comedy]

That is plywood? I usually cut a piece to fill the hole, then back it with a larger piece inside, against the hull. Use screws and glue (epoxy).

If you want to re-drill it, no biggie.

[tartansailboat]

Mo, I am having trouble visualizing how you used a dremel tool to remove the old thru hull. Can you explain in more detail what kind of diamond cutter you used? What did you remove to get the tool inside the hole? A picture or diagram would really help.

[tenders]

In my opinion hacking out through-hulls is the perfect job for a Sawzall, and is punching above the weight class for a Dremel.

[sastanley]

tenders, I went straight to an 8# mini sledge and beat mine out..

[romantic comedy]

I use a threaded rod, to make a puller. A lot less damage to the boat.

[jwmurphy]

Thru Hulls

I'm the original owner of a Bristol 27, #364, 1975.

The cockpit drain thru hulls it came with consisted of fiberglass(?) pipe glassed into the hull with hose up to the cockpit drains. No seacocks, valves,etc.

I, too, never liked this arrangement. But, as you implied, it requires removing the engine to make a proper refit. (Yikes, 38 yrs. has gone by and I've still not adressed this issue)

Your ball-cock solution might be an interim step until such time the engine is removed.

Jim

[TomG]

So yesterday, while working on my major rehabilitation projects, I started work on the first of my thru-hull replacements. I started with the galley sink drain. I presume this thru-hull is original to the boat ('77 Tartan 30) and is a simple bronze or brass 1/2" nipple glassed into the hull. This is not a mushroom head or recessed head thru-hull. As I started to take the ball valve off the pipe with a crescent wrench, the entire assembly simply screwed right out of the hull! This thru-hull might be the easiest change ever.

[hcrisp]

Bronze thru hulls

I am in the process of changing the cockpit drain thru hulls on my Bristol 27. Mine consisted of 1 1/2" OD FRP tubes from the cockpit sole to 1" brass ball valve and thru hull. To make matters worse, someone had cobbled a plain steel pipe connector and steel nipple to the ball valve to get the diameter up to the 1 1/2" ID hose. Finding all this was a bonus for removing the engine to work on in the shop over the Winter.
Everything I have taken apart has needed it. To be taken apart. Plus, it's fun.
The pic below shows the parts I think are right for this job - 1 1/4" stuff. If anyone has a better idea (or less costly), I am all ears.
Howard

[ILikeRust]

Here's how I removed my through-hulls.

I took an angle grinder with a metal-cutting disk and cut through the outer ring of the mushroom, as so:



It was then extremely easy to take a hammer and cold chisel and snap those little pieces off, leaving just the little metal sleeve of the through-hull going through the hole in the hull - and actually, once I snapped off the outer pieces, that little metal sleeve fell off inside the boat:



I then had the yard grind down and glass over the two holes that were left behind. You almost can't even tell they were ever there.