Sewer Work

[Roger Long]

What a difference a day makes. Yesterday, I was out on the deck in the sunshine doing sailor kind of stuff. Today, I was down in the deepest recesses of my boat’s unmentionable parts doing stuff you couldn’t pay a plumber to do.
This is the bilge sump in the aft end of the keel. It’s about a foot long and six inches deep behind the second fuel tank installed in the keel ahead of it.

The red cable is the gear shift and the plywood pad just visible is set into the structural glass on top of the fuel tank for mounting the two high level bilge pumps. The sink, icebox, and shower drains go into this sump which is emptied by a small bilge pump with an integral float switch. The same pump handles any incidental water such stuffing box leakage and condensation. It’s a system which has worked out very well in practice and never caused any odor. I keep a plastic strainer basket stuck over the end of the galley sink drain to collect any food waste that gets down the drain.

The indentation at the top of the picture is a sub sump for the manual diaphragm bilge pump hose which has a foot check valve on it. Centrifugal pumps should never have check valves BTW.

There is no structural problem but the layers of glass I lined the sump with as a backup barrier to protect the structural glass work succumbed to the witches brew of hot water, soap, bilge cleaner, and oil. They began to separate and peel away from the hull structure. I forgot to take a photo but it was quite a mess with softened glass flaps hanging into the sump.

Although the sump is only six inches deep, the bottom is just reachable with the tips of my fingers and access is normally blocked by the primary fuel filter and pump as well as the bilge pump hoses. So, once again, I am at Waterman ‘s Wharf with my boat disabled. I had to disassemble the fuel system and plug the hoses with machine screws. It was also necessary to disconnect all the bilge hoses. The galley sink now drains through the engine cooling water through hull and the ice box melt water drains into the wine bottle just visible at the top of the picture.

After getting all that apart, I went at it with a box cutter knife and cut out all the loose fiberglass and did an initial cleaning. That’s enough for one day. Tomorrow, I’ll clean and grind to try and get down to a surface that will take a new epoxy and glass liner. The new glass will go completely around the sump so there is only one edge showing and the whole thing is mechanically locked into place. Since that edge will be epoxy on epoxy instead of epoxy on old polyester, it should hold. Doing fiberglass work at arm’s length in this tight space should be enough to make one take up stamp collecting.

So, you want to be a yachtsman, do you?

 

[Scott T-Bird]

Good luck! Was it the peeling fiberglass that instigated this project or was there something more urgent that needed attention? Everytime I have to reach down into my bilge, I come away with scraped knuckles and odd little puncture wounds in my finger tips. It's comforting to see how my blood mingles with the oil. One time I reached deep underneath the floor board along the curvature of the hull just to pull whatever gunk I could find only to retrieve a mouse skeleton. I bought rubber gloves after that episode.

Yes, you are quite the yachtsman! I hope you put your blue blazer and white cap away before soiling your yachty clothes!

 

[BobT]

On the positive side, better a little busted knuckle stinker than some white knuckle episode.

 

[Benny17441]

Can't quite understand why the sink drain is directed to a bilge sump. It is very difficult to stop food oils and particles from getting through and hence bacteria growth and odors. Even if the gray water is treated I just can't think of a good reason to justify it.

 

[CalebD]

Roger,
It is dirty work but someone has to do it!
You will be glad when it is all done.

 

[Roger Long]

Can't quite understand why the sink drain is directed to a bilge sump. It is very difficult to stop food oils and particles from getting through and hence bacteria growth and odors. Even if the gray water is treated I just can't think of a good reason to justify it.

Enough soap goes down with everything else that there has never been any odor as long as I keep the strainer basket on the end of the galley sink drain cleaned out.

I don't like direct discharge sinks. Floating stuff goes down and stops at the waterline. Other stuff then goes down and sits on top and you soon have a clog. My system minimizes the number of through hulls to keep track of and open and close (3 for the whole boat).

I wouldn't dump hotel systems into a large open bilge with a lot of surface are as you would be forced to do in most modern boats but this small sump keeps the water contained.

Looking at the fiberglass and epoxy I'm pulling out, I think that the final layer never cured properly. I was working in the winter in difficult conditions and I either mixed it wrong or it never set up in the cold.

 

[TomY]

That opening your site to see this "problem", is a joy in comparison. You've been on your way engine problem free long enough, I'm convinced you have it licked.

My last boat could be a real stinker. The ice box drained into the bilge(sinks overboard). But that sump was open. My "new" boat, 51 years old, has the original plumbing from Alden. The icebox drains into an enclosed fiberlglass sump(with an access panel on the top I've never removed), just forward of the deep bilge that houses the bilge pump.

The icebox sump outlet hose goes up to a hand piston pump below the galley counter. You reach through a small door to pull it. The discharge hose on the piston pump runs to a T(well above WL), below the sink drain/basket at the galley sink.

This is completely odor free and we put more food through the box with 2 kids and friends for over a decade, than most boats will in a lifetime. There's never an odor.

But the best part is what this system does for the sink drain. As you say, I find galley sink drains problematic(poor plumbing design). Even though I have fitted a tight basket that screws in, junk and stuff get by(dishes for 4+ several times a day). That as well as cooking oil or whatever, inevitably fouls the drain, in no time.

Back to the best part. Screw down the galley sink basket, and pump the ice box sump a few strokes. Voila. It blows the sink drain line free every time. I've never had to clear the galley sink drain on this boat.

Sort of a hard project for you right now, I know. And for those not fond of adding through hulls, I understand. I'm diligent about closing it along with the engine intake when leaving the boat. There's nothing worse smelling than my last boats bilge(a Cape Dory).

 

[Benny17441]

I see your point but I do not see a beneficial trade off. Keeping track of 4 through hulls is not much harder or that much more expensive than 3. A direct discharge sink will be slow in draining if the boat ain't moving and particles can indeed float around inside the hose at water level but since we only use the sink on trips or outings when we are mostly underway we have had no problems. The sea water pushing past the through hull opening sucks the gray water out of the hose. I could see where a liveaboard that seldom moves the boat could have problems. I understand the beneficial points of your system but it is the maintenance downside that may not justify it for me. We all have our preferences.

 

[Roger Long]

Don't you love it when a project takes half as long as you thought it would?

This little rasp bit and the flap grinder chucked in my cordless drill cut down to sound and dry fiberglass very quickly.

Working with the epoxy and glass was surprisingly easy since it is a sump. I just mixed up the epoxy and poured it directly into the sump. I then used a brush to pull it up where I needed it. I kept adding glass layers until the resin was used up.

Instead of flaps dependent on adhesion to the keel sides for a water barrier, I now have a nearly structural layer around the entire sump. Even if it should separate a bit at the top edge, it shouldn't be a problem.

When I checked out of the hardware store with the grinder bits, brushes, West epoxy, and other stuff I needed, the bill was a $189.00. People who think building a boat is a cheap way to get one, take note. Of course, if I was home, I would have had a lot of the stuff on hand and could have bought a smaller amount of epoxy at Hamilton Marine but these kinds of bills are the price of cruising on a boat with limited storage space. I make it up in dockage fees.

Oh, wait a minute, I am home.