Advice needed - C-Change 25 hull penetration

C

C-Change

New member
I mentioned in my recent post that I would probably have a few questions regarding the 25 cruiser we just purchased. The questions have started :lol:

This boat came with a raw water washdown pump system and the thru hull appears to be in the cabin step area. (pics below) I hate thru hulls and avoid them if possible, but this one is already there. I am not certain if the washdown system was added by the factory (Fluid Marine boat) or if it was done by rigger/dealer Sportcraft Marine in Oregon. I called Sportcraft and tried to ask how the thru hull had been installed (i.e. was the balsa cut back and epoxy added to seal the balsa), but was told they were too busy to discuss it with me. I am already somewhat concerned since the strainer appears to be screwed into the bottom of the hull, there is no backing plate on the interior of the hull and the valves seem to be Home Depot type ball valves. The boat will spend most of its time in the water.

So... the bottom line is that the boat arrives this weekend and will go to the boat yard to have the bottom epoxy sealed and bottom painted. I am thinking of having the yard remove the thru hull and verify that the installation was properly done, then add a backing plate and a proper bronze seacock, or removing the thru hull and repairing the hole. Am I being too conservative here? I also hate spending $$$ if It is not needed, and I suspect that this will not be cheap. I could also see if the yard would let me do the work. Or I could wait a year and do it next time it is hauled.

The surveyor took the pictures but the only comment regarding the thru hull was that it should be connected to the galvanic bus.

Any thoughts from folks that have a similar setup?

Jan

IMG_9823.jpg


IMG_9749.jpg
 
Jan, Mine is not a 25 but it looks about the same as yours. I might guess that it was installed by the factory, not the rigger. JMHO. I have not pulled mine (for a fresh water washdown) but it is going to go away at some point. It is wired to a ground (?). Don't much like holes in the bottom of my boat either.

Harvey
SleepyC :moon
 
My vote would be to pull the through-hull and do it right by checking the core sealing, and installing a proper seacock.

Even if you don't need the wash-down, you might want to install a toilet or air conditioner at some point and would need it. And it will be much easier to do this than to do a proper repair of a hole in the hull.

BTW, mine was installed at the factory, and was not sealed and was a standard NPS ball valve. Only one of many shortcuts that needed to be fixed.
 
I don't have a 25 but our 23 came with one factory installed raw water wash down.I suspected it was leaking as when it was removed water came out. I had it removed the hole plugged and glassed over along with the two fish box drains the 2008 Ventures came with. I did leave the pump that was connected to the thru hull and the other related plumbing. After the thru hull was removed I simply added a long hose to the pump and a strained pickup so if I want a raw water wash down I simple throw the hose over the side and connect the washdown hose to the normal fitting turn on the pump and I still have raw water wash down. Can also be used to pump out other boats or as an aux bilge. Just my opinion here everyone has there own way of doing things. All these ideas came from Pacific Wander's album, thanks Ross. The less holes below the water line the better.
D.D.
 
Brady, how well I remember you trials and tribulations!

Minnow":1jmrefi5 said:
My vote would be to pull the through-hull and do it right by checking the core sealing, and installing a proper seacock.

Even if you don't need the wash-down, you might want to install a toilet or air conditioner at some point and would need it. And it will be much easier to do this than to do a proper repair of a hole in the hull.

BTW, mine was installed at the factory, and was not sealed and was a standard NPS ball valve. Only one of many shortcuts that needed to be fixed.
Click to expand...
 
Jan,
I don't know if there were changes in things between your boat and mine (2005), but the valve under the step into the caabin on my boat is the raw water through hull for the head. Mine is also a common ball valve. I don't use it so I have had it in the off position for some time. I have no raw water wash down so don't know where that would have been installed.
 
Thanks for all the replies. What a great place :) I asked the question last night and wake up this morning with a lot of helpful replies. I am leaning toward just having the hole plugged and glassed over. Since we will be adding the epoxy sealer and bottom paint, I am not worried about matching gelcoat or a perfect external finish so that should help keep the cost down. I think a fresh water washdown would be preferable anyways, so I'll probably just plumb the line into the freshwater system.

David, I don't think mine is a raw water intake for the head since the head is freshwater fed with an integral holding tank.

Jan
 
When I had a raw water wash down added to my TomCat, I had the intake routed through the transom well above the water line. Les and Carl at Eq used PCV piping down the aft side of the transom to get the fill line below the water line. I feel more comfortable with this arrangement than a through hull. The PVC is located and cut in a way to less the likelihood of it getting clogged and there's a strainer in the transom locker just in front of the pump. If it were me, I'd seal the through hull entirely and re-route the raw water wash down in a similar fashion.
 
I'm only going by what I see in the photo, but several things don't appear to be "best practice" in that installation. I'm perfectly happy to have a proper through-hull in a boat, but I do not like to have one that I am going to have the slightest worry about. This one would make me worry.

A few things I see or wonder about:

1) Was the core closed out - it doesn't look like it.

2) I see no flange, which to my mind a proper seacock should have (it should resist side forces such as gear falling on it or someone kicking it, as per ABYC).

3) That 90º elbow look like brass. Brass is a no-no for underwater fittings. It should be bronze (and I can tell it isn't).

4) Is the valve itself a "no-name" one? If so I would suspect brass or other non-wonderful components.

5) Is the valve NPT threaded? If so, it is likely to be "jammed" onto the NPS through hull, and there may only be a few threads (somewhat) engaged. It should be NPS (and maybe it is, but I would want to check).

6) Is that white hose rated for below-the-waterline use? I would usually want to see something like wet-exhause hose which is rated for that.

7) I don't see any particular reason for that outside grate. They can be a pain as they clog easily with barnacles, detritus, etc. and you cannot get to them without a swim or a haul. Also they have to be removed to really clean out. And were those holes in the core closed out properly? I would prefer an inline strainer inside the boat (that I can get to) and just a plain through-hull on the outside (if it does clog out there, still easier to clean). Some through hulls need the effects of an outer "scoop" at speed (intakes, etc.) but this one doesn't (and if it did they make some that hinge open for cleaning).


A few thoughts that I might have, if it were mine:

1) Is this water supply necessary, or is it for something obsolete or not useful to me?

2) Can the through hull be relocated above the water line? (Probably not, and there is nothing wrong with a proper one below the waterline, but I would still start my thought process here).

3) If not, can it be put in a non-cored area? Is the little depression near the transom (if you have one on the 25) non-cored? If so, can this go there?

4) If either of the above can happen and are desirable, I would eliminate this through-hull altogether, and patch the hull properly (this is not difficult to do with epoxy/fiberglass, and will be extremely strong and reliable. Also, since it's on the bottom, while you want to be tidy and careful, it doesn't have to be *perfect* cosmetically (unless you want it to be, which is always fine).

5) If keeping the through-hull and keeping it where it is are the plan, then I would remove it and re-do it properly. I'm guessing that height is probably an issue (?). There are special seacock bases for tight areas. I'm not as fond of them as regular ones, but they would be an improvement. Bronze will be "smaller" than Marelon (reinforced plastic), which I think (I usually use bronze) tend to be bulkier. A few things that would be included for me in a "proper" install.

a) Close out the core*.

b) Use a seacock with a flanged base, and connect that to the hull in one of several acceptable ways.

c) Use a US-made bronze (it is easier to know what grade of bronze you are getting) or a Marelon (probably too bulky) through-hull.

d) Same goes for the seacock. I prefer either all-US-bronze wetted parts (except the ball which can be chromed bronze, 316 stainless or acetal), or Marelon (probably too bulky).

e) Support the seacock base on a fiberglass backing block bonded to the hull, and attach base and/or pad to the hull (several options).

f) Bronze (if using a bronze system) elbows, etc.

g) Hose rated for below-waterline use and a proper clamp (AWAB or similar) (note that two clamps are not required for water intakes and can be counterproductive as the hose barb is often not long enough to accommodate two clamps and their spacing and so the second one starts to "fall off" the barb and is actually stressing the hose).

h) Ascertain whether or not a siphon break is needed (probably not as your "recipient" is probably above the waterline).

:hot

*In most areas, this consists of "reaming out" some of the core and filling with thickened epoxy, then re-drilling the hole. However in a below-the-waterline area, there is now some thought (and evidence) that this is not always adequate. So the "best" way now is probably to close out the core completely (i.e. you remove the core in a larger radius, and then use fiberglass/epoxy to re-laminate the hull so that there is no "thickness" in the way of the through hull but rather the inner and outer hull are "pinched" together. Hmm, that's not very clear. Think of pinching your thumb and forefinger together flat up to the first knuckle - that is the closed out core, and the remaining open area between the pinch and the web of your hand is the cored area, vs. if you left your thumb and forefinger an inch apart and filled them with thickened epoxy up to the first knuckle (the usual way which is still fine in most circumstances).

Where I first read about this was in an issue of Professional Boatbuilder, although I don't have it to hand [Edited to add: I found the Professional Boatbuilder article online, and here is a link to it: http://www.bpspecialprojects.com/PDF%20 ... SEOUTS.PDF ]. As I remember it, they were finding core problems in cored hulls even when the openings had been taken care of (thickened epoxy, etc.). Well apparently in some cases the cores still were able to soak up moisture in a very large area. What contributed to the problem was pressure/suction caused by the hull heating up and cooling down over the course of days/nights, which caused it to "breathe," and thus draw in air/water wherever it could (the through hull areas where some epoxy might have cracked, areas where wiring or other hardware had been screwed into the core, etc.). In some hulls there were then also tiny pathways (say between the grid blocks of balsa which are usually filled in but may not be perfect), so the hull was able to turn into a large "system" of heating/cooling/sucking. I know, this sounds scary and may be "alarmist." It certainly doesn't happen on every hull (and I would be nearly certain yours is fine now, but then that's why you are going to improve it :thup My guess is that the usual method of reaming/filling/overdrilling works in many below-the-waterlne cases, and is MUCH better than doing nothing at all; however, I think if I were putting a through-hull in a cored bottom today, I would close it out all the way. I don't like to worry, and it's not that much harder once you're doing it anyway.

Balsa is more resistant to water wicking than some other "shapes" of wood, but it is still very capable of doing so (there are many very wet balsa decks, for example). So I still take plenty of care (and then don't have to worry!) (I do think balsa is a great core material for several reasons, and I have used it to re-core boats of my own, so this is not a knock on balsa, but just added because I have read that "vertical-grained balsa won't wick water." It is more resistant, but not immune.

PS: Sorry, I see this is long and there are no photos and few emoticons to break it up :wink:
 
I talked to the folks at the boat yard today and they quoted about $300 to plug and glass over the hole. So, that is the way I am planning on dealing with this issue. Thanks again to all who provided information.

Sunbeam, thank you for the very complete and detailed posting. I read and learned from the linked article as well.

Jan
 
You're welcome, Jan. I'm glad you were able to "wade" through it :wink: Just curious: What did it turn out the through-hull was for?
 
I have not actually seen the boat yet, it will hopefully arrive on Friday. :) However, I am convinced that the thru hull is for the raw water wash down system. The previous owner listed the boat as having a raw water wash down. The surveyor mentioned the thru hull was for the wash down. The head is fresh water fed, there is no air conditioner, so there is really nothing else I can think of besides the wash down system. I'll check for sure once I see the boat and report back if is different than expected.

The boat yard quoted the price based on a 3/4" to 1" thru hull.
 
Sunbeam,
Good to see someone else concerned about core issues. I'll address this further when we return home. The article is good. However it I did not see where it stressed the secondary bonding of Epoxy vs vinyl or poly ester resins. In my opinion epoxy is the material of choice, and the surfaces must be properly prepared. Proper under cutting can be adequate on a C Dory.

On the other hand an improper " plug" anv a layer or two of glass and polyester can be down right dangerous ( I am aware of several boats sinking from a less than proper " plug" and glass over--not a C Dory)
 
I agree on the epoxy/secondary bonding superiority. Although I guess it was not specifically mentioned in the article (it's been a while since I read it), I think that particular magazine - and it's intended audience - is already in agreement that epoxy is generally the way to go. So it may have "gone without saying" in that case (not that it would have hurt to clarify it).

Just to expound on what Thataway brought up:

When you are first laying up fiberglass cloth and resin, you get a primary (i.e. chemical) bond. This is the best bond. However, after a certain amount of time has passed (measured in hours or at most perhaps a day), you can no longer make a chemical bond. After that stage, all bonds will be secondary (i.e. mechanical) in nature. In other words, you count on roughing up the surface to be bonded to, to create "tooth," and then your new work to "stick" to it mechanically.

Of the three common boatwork resins that I'm familiar with (epoxy, Vinylester, and Polyester), epoxy is generally accepted to make the best secondary bonds. Vinylester comes in second, and Polyester comes in a more distant third.

So why would anyone use Polyester for later work? I can think of three reasons:

1) Some people reason that since the boat was built with Polyester (if it was, but most older, and many current, production boats are). I don't think this is a valid reason, but I can see why people would come to that conclusion just by "gut logic."

2) Polyester is a lot cheaper. I don't think that makes it worth it, but not everyone thinks the same way.

3) Polyester and Vinylester generally cure faster than epoxy. In boatyards time is money, and being able to get a repair done all in one trip (out to the boat in the repair yard) vs. having to wait and go back out a time or two in between other jobs, means money.

Note that this doesn't mean Polyester built hulls are weak. Polyester is not as "premium" or as water-resistent as epoxy, but it does seem to bond fine in a primary bond (when the boat is built), and properly built Polyester hulls do not tend to delaminate. Where you may see problems is with secondarily bonded (tabbed) bulkheads and the like (done at the builder but maybe too late for a primary bond). Still, problems don't always occur; but it's just that epoxy makes a much better secondary bond.
 
Captains Cat":1gyjmdwm said:
Roger, what about the Armstrong Bracket?

Charlie
Click to expand...
Charlie,

There's space along side the bracket to route the intake. I'll take a picture and post in the next few days. It would (of course) be even easier to go this route on a 22 or 25. Personally, I see no reason for a through hull when you can go this route. In addition, it's a lot easier to deal with an potential obstruction since it's really easy to get to.
 
A fourth reason is that some workers are just more comfortable working with polyester, because that is what they have done for years. When I first cme to Pensacola 20 years ago the folks who do the heavier jobs i can no longer do, did not feel comfortable using epoxy. With time they have learned where it is best, as well as how to use it so the repair is as quick as polyester. Sometimes they tell me why they think polyester will be better ( for example where gel coat adherence to a repair is important)--although gel coat can be put on epoxy, with a tie coat and proper prep, it is better on polyester.
 
Back
Top