Cape Dory 25D seacocks

[Sea Hunt Video]

After action report:

I was successful in removing the old thru hull fitting with the "radiator spud wrench" or "step wrench" I bought from Chicago Faucet. It worked perfectly. A vise grip and a little muscle and it unscrewed without a problem.

I then checked the backing plate. I thought it was in OK condition but it felt "soft" (or mushy). I decided to replace it as well. I was able to get most of it and the sealant off with a chisel. The remainder came off with a Dremel.

I will shortly install a new backing plate (5" diam; 1" thick) and then assemble the seacock, etc. once the back ordered thru hull arrives from Spartan Marine.

A question. My thought is to apply 3-4 coats of Cetol Marine Natural Teak and 2-3 coats of Cetol Clear Gloss to the backing plate. Is there something else that I should use I have read where several folks have applied 1-2 coats ( ) of epoxy. Unfortunately, I have no idea how to work with epoxy and am hesitant to start with this particular backing plate.

[Oswego John]

Hi Robert, Congratulations on your progress re the new seacock and through hull fitting.

I have no real objection to applying epoxy over the finished backing plate. In my mind it is sort of redundant using a belt while wearing suspenders to hold your trousers up. Whatever your choice of wood finishes is, cetol is very acceptable. I would say that up to seven coats of protection is certainly adequate.

The first thought that came to mind is that you plan on using one inch stock for your backing plate. Will this stock be compatible with the curvature of the hull at the location of the seacock?. There is very little to nothing of flexibility to one inch wood. Will you have to contour sand the plate for an acceptable contact fit?

Is the backing plate made of cut lumber or from 1" marine or WP plywood. Whatever the choice, remember that the most vulnerable section for wood rot is through the end grain. Before time for installation, all sides or the plate must be treated, front, back and especially all of the edges. Adequate penetration of the sealer must be allowed for, timewise. If contour sanding is necessary, contour the plate first and only then you apply the sealer

One last thing, take adequate digital pictures before and after every step of your project. It is okay to let the pix sit in your camera as long as is necessary. Hopefully the followers on this board will enjoy them shortly after college Christmas break.

Here's wishing you great luck with your project.
Knocking on wood for you until my knuckles bleed,
O J

[Sea Hunt Video]

OJ:

Sorry for not being clear. I am using a round teak backing plate (5" diam; 1" thick). On the CD 25D the intake hole for the seacock is along the side of the hull and is fairly straight, although there is some curvature. I was planning to contour sand a portion of the teak backing plate to get it matched to the curvature and then apply Cetol Marine Natural Teak and Cetol Clear Gloss.

I am wondering if Cetol is sufficient for this teak backing plate or if I should use something more "waterproof".

While I would like to take digital photos I do not have a digital camera. I buy Kodak disposable 24 shot cameras for $5/each.

As for posting photos on this website, as you know, this is a sore spot with me. I do not have a clue of how to do it; waiting for "Fifi" and her Christmas college break is probably not a reasonable alternative.

[Oswego John]

Robert,

It is now time to revert to "Plan B"

Take shots of the pictures that you want with the throwaway camera. Take as many or as few as you want. You don't have to use all of the film. They only charge for the pictures that are developed and printed.

Get hold of that 10 year old kid that gave you the "dinosaur" look. Ask him real nicely to put each print into your scanner and download them into your computer. Give him some milk and cookies, (give his father a Guinness) and ask the kid to send the pix to the CD forum. FWIW, try to be nice with this new breed of techie nerd. You're gonna need him when you redo your woodwork or other future projects.

As for totally waterproofing the backing plate. Think about buying a quart of deck sealant like Woodlife or Lumberlife. Pour it into a shallow pan and cover the plate with the sealant. Lay a sheet of plastic wrap over the pan to retard drying out. Keeping it in the shade will help. Soak the backing plate in it until it won't absorb any more sealant. Flip it over from time to time. The finish of the plate won't be as aesthetically pleasing using sealant as it would be when using Cetol. Life is a compromise.

O J

[Ron M.]

I replaced all backing blocks on my thru-hulls with 1/2" FRP,( fiberglass re-inforced polyester) from McMasters-Carr. Very tough stuff and it will never rot, delaminate, or need finish.

[Maine_Buzzard]

Chiming in-

Highly subjective opinion here...

Don't fiberglass a teak block to the hull. The bond would eventually be worse than using bubble gum.
Don't bother with Cetol on the block, it will flake off in two years. Paint would be easier to put on, and last longer.

Teak will last 25 years with or without any coating, but will eventually get punky and weep.

If you use the teak, fit it to the curve of the hull and use 5200, 4200, or Sitkaflex 291, according to your preferences.

I followed Maine Sail's way cool thread on making fiberglass backing plates, but modified it slightly by cutting circles of glass cloth and layering them with a roller. (rather than making a whole cookie sheet of laminate and cutting a circle out of it. Epoxy is too expensive.)

They were then bonded to the hull and redrilled.

Fiberglass and Epoxy is very easy to work with, and about $100 gets you set up to do just about anything. Backing plates would be a great starting project, and you have little risk. Anyone near you that works on it?

Here's a shot of the backing plate in the lower left, during my repower. I have a better series of images to show the installation. I also did the sink drain here. I will probably do the cockpit drains and head intake this winter.

[Ron M.]

the raw water intake seacock is the only one I didnt make a backing plate for, seemed to me the 3/8" engine pan was more than sufficient. I did make certain it was well bonded to the hull in that area. Also replaced the original spartan valve with a groco ball valve which I found easier to work in that tight space.

[Sea Hunt Video]

I am getting ready to install the new 3/4" Spartan seacock and thru hull for the marine head intake located in what is the forward Vberth. I have "dry fit" everything and it looks OK.

I have a question about sealants.

I have three areas in which I need to use sealant: (1) securing the teak backing plate to the interior "wall" of the forward Vberth. I think the wall is the standard Cape Dory interior lining material - some type of plastic ; (2) sealing the bronze plate of the seacock to the wood backing plate; and (3) sealing the bronze thru hull to the exterior hull.

The "bottom" of the teak back plate has not been touched. It is the original teak. The "top" of the backing plate has 3 coats of Cetol Marine Natural Teak and 2 coats of Cetol Clear Gloss.

What "sealant(s)" should I use I am considering 3M5200, 3M4200 and Sikaflex 291 LOT. From material I have read I am leaning toward Sikaflex 291 LOT for all three of the above applications.

I am also planning on using 3M Premium Filler to cover over and fair the area where the two bolts are inserted through the hull to attach to the seacock. I think Maine Sail had recommended 3M Premium Filler for this use in his tutorial but I am not positive.

Thoughts and wisdom of the board

Thanks in advance.

If I stay on my current schedule I may be back in the water to have Thanksgiving dinner aboard. Yea

[Sea Hunt Video]

An update:

1. A few weeks ago I installed the teak backing plate. Used 5200 sealant. Worked very well. Used old thru hull and seacock to make sure I had backing plate positioned correctly.

2. Today, with the help of a good friend who actually knows what he is doing, we installed the new thru hull and seacock. Randy Drummond, CDSOA poster, and caretaker of S/V Twig (Cape Dory Typhoon Weekender) took time from his busy schedule to help with the installation. It actually went pretty smoothly except for me making a bit of a mess with the Sikaflex 291. A nice guy in the boatyard let me "borrow" some acetone and we managed to clean up the teak base plate.

The exterior thru hull (Randy's responsibility) looks like it was installed by a master craftsman. It's perfect.

Tomorrow I will fill and fair the screw head countersink areas with 3M Filler. Hopefully, the bottom will get painted Thursday or Friday and splash Monday. Yea

Now, hopefully, when S/V Bali Ha'i motors back to her home at the sailing club, there will not be any leaks.