1996 MONTAUK 17: Leak at cockpit sump drain

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
MattFL
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Re: 1996 MONTAUK 17: Leak at cockpit sump drain

Postby MattFL » Tue May 04, 2021 4:37 pm

In regard to the holes not lining up; the transom layer was thicker than I expected it to be, followed by the foam, followed by the inner skin of the boat actually being thinner than I expected. I get the impression that they drilled inward from the outside of the boat at a slight upward angle (too much of an angle), then the foam was so soft it allowed them to slightly change the angle by the time they hit the inside skin, or they drilled the inside hole from inside the boat. In either case, the problem was with the hole through the hard layer of the transom being at slightly too much of an upward angle. I hope my explanation was clear enough to understand.

I was expecting the bond to be much stronger too. Although there was not a lot of bonding surface area so that may have been why it was so relatively easy to break the bond. I did have to give it a good twist, it was not going to fall out or be twisted out by hand, but with the 12" pliers it was not difficult.

jps10
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Re: 1996 MONTAUK 17: Leak at cockpit sump drain

Postby jps10 » Thu May 06, 2021 3:50 am

I'm late to this thread, and it sounds like the original query is resolved. I want to contribute what worked for me and my [1987--always use four digits for a year] Super Sport [17--always specify the model length designator] conversion or any 17-foot hulls that might prefer an alternative to brass or poly drain tubes.

When I got the [1987 SUPER SPORT], I concluded that replacing the original brass drain tubes {with another brass tube] would NOT be best for my planned use: immersion in the Pacific Ocean year round. Between the passive corrosion of saltwater immersion and potential stray currents from nearby boats with shore power constantly on, I didn't want to risk a leak from brass tube corrosion.

For that reason I replaced the original brass drain tubes with fiberglass tubes, laminated into the sump and transom openings. [Using FIBERGLASS overboard drain tubes as replacements for original brass drain tubes] is a good way to go if the boat will live in the water.

jimh
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Re: 1996 MONTAUK 17: Leak at cockpit sump drain

Postby jimh » Thu May 06, 2021 9:52 am

jps10 wrote:...I replaced the original brass drain tubes with fiberglass tubes, laminated into the sump and transom openings.


Q26: where can fiberglass tubes be sourced?

Q27: how do you go about laminating a fiberglass drain tube into an opening hole?

Generally the action of lamination is the joining of many thin layers to create a thicker material, with the layers being adhered together and laid up while the adhesive component that will hold them together is still curing, so that all bonds are primary bonds.

Your new and unusual method using fiberglass tubes perhaps should be the start of a new thread

Also,

Q28: what material do you mean when you use the term "poly" as in a "poly" drain tube?

There are many materials that begin with "poly" such as polyethylene, polyurethane, polyvinyl chloride, and these materials have different densities. I don't think "poly" is a particularly precise term for defining a material.

jps10
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Re: 1996 MONTAUK 17: Leak at cockpit sump drain

Postby jps10 » Thu May 06, 2021 2:28 pm

Jim and all others interested, when I say "poly", I'm referring to the replacement part that MattFL called plastic; not sure if its just PVC or if its a hybrid that BW or TCmarine suggested as an alternative to the brass tubes.
In this thread, PhilT and ConB make some good points on the tube alignment between the 2 surfaces being connected, and why the brass tube w/flared ends works well enough for the purpose. Also pointed out in their posts [as well as Jimh], is to NOT use 5200 in this case. The web is packed with cautions and advice regarding 3m5200.

Regarding Q26:
In 2013, I had difficulty locating f/glass tube of 1" ID to accomodate rubber expansion drain plugs. The product I used was 1.25" OD x 1" ID. I'm almost 100% certain the product is known as 'Extruded' or 'Pulltruded' fiberglass composition, basic white in color and is dimensionally high toleranced. I still have a 12" length of that tube leftover since I bought more than required, not knowing if I would get my 're-tube' right the 1st time and knowing I would need an extra 6" to retube the splashwell drains.
At the time, I found a company in Costa Mesa, CA that produced an assortment of fishing products [gaffs, dipnets, to outriggers]; they used an assortment of this tubing and the owner was nice enough to just give me a 2' section. Unfortunately, they're not in business today, but I think a successor company continued that business [same owner, new name/location?]; they're called 'Blue Water Bait Systems' and they are also somewhere in Orange County, CA. I looked up their website and their specialty is fiberglass bait tanks and associated products, so its likely they could refer you to their source, or maybe they will sell short lengths online.

I will continue this sometime tomorrow; running short on time and I want to give an understandable recollection of my steps in the install of my drain.

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Phil T
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Re: 1996 MONTAUK 17: Leak at cockpit sump drain

Postby Phil T » Thu May 06, 2021 3:14 pm

There have been 4 or 5 owners I know who have replaced their drain tubes with fiberglass tubes. Several owners fabricated their own out of cloth and resin.

A few owners used a manufactured product like this:

https://mgs4u.com/product/1-14-od-round-tube/?attribute_pa_length=6-inch&attribute_pa_color=gray&gclid=Cj0KCQjw9YWDBhDyARIsADt6sGY2fE3s5V-xpFWoPO2pBNYfeCnJFlYgH4zToDA8Cd85YoX9UChyxQoaAvtLEALw_wcB

One owner filled the existing holes with fiberglass and resin and cut out the drain hole and left it open.

In my view using fiberglass or PVC or other type of plastic takes more planning, shopping, fabricating and technique than the already proven and documented brass drain tubes.
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