What type of thru-hulls are these?

[One Chance]

I used a sawzall to cut out my thru hulls- cut off flush against the hull inside then cut the remaining piece into 3 sections from the outside thru to the inside & take a punch & knock out the sections - works very well & does the least damage to hull. Still need to make fiberglass repair to the hole. There are many opinions on the best way to complete the repairs & filling the old hole.
Perhaps you will get some good advice on this blog.(I am also looking for good advice on filling these old holes after removing 4 thru hulls on my boat). Too cold here in NY at this time to do fiberglass work! Smart move judging from the age of these fittings.
good luck!

Fair winds

One Chance

[ElCapt Drew]

Originally Posted by Lodesman

Why is it that you don't want to keep using the Blake? They're pretty bomb-proof, and easy to maintain.

Appreciate the diagram; I don't have any issues with the Blake fitting itself, more just the age of the fitting. She's a 1971 and who knows if that fitting has ever been replaced. Coupled with the fact all the fiberglass work around the fitting makes me wonder about the integration of the installation. I would just feel more comfortable with a more standard approach that I know works well.

[HopCar]

There is probably nothing wrong with the Blake that a little cleaning and polishing wouldn't fix.

If the second thru-hull is below the water line, you should install a real flanged seacock or Groco Flanged Adapter and ball valve.
Groco Flanged Adapter IBVF

[George DuBose]

If you have a bronze screen on the outside of the hull remove that. Then take a burr or a carbide rotary file, chuck it in a drill or a Dremel, from the outside of the thruhull, grind away the inside of the bronze tube where it meets the flange, you will be able to separate the flange from the seacock and then remove the seacock from the inside of the hull. All your fiberglass should be untouched.

[One Chance]

George
What a great idea! Never gave the rotary file a though.
Thanks for your insight.
fair winds
One Chance

[George DuBose]

To be more clear, one take's a rotary carbide file chucked into some kind of drill or Dremel and from OUTSIDE the boat, one grinds away the inner most edge of the thruhull's hole. This will allow the flange outside the thruhull to be removed. If one takes one's time, there will be no damage to the fiberglass, just a new thruhull needs to be purchased.

Frozen seacocks can be soaked in an auto parts cleaning machine for easier disassembly.

I think most seacocks are frozen from lack of usage.

I cleaned Skylark's seacocks on a bench grinder with a soft wire brush and they looked totally new. I will get another 40 years use from them.

[sestina]

Why on earth get rid of bronze and replace with plastic? I've serviced Blake seacocks that where fitted in the 1930s.