Sewer system diagram

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CEC

Senior Member
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Apr 3, 2018
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125
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USA
I'm working on planning changes to my head plumbing in C&L 37' aft cabin Trawler and have some questions that I'm not finding in my searches. In a couple posts I have seen comments about "having no pump is best" referring to macerator type pumps and using the ocean to pull. I cant do that in most cases though hence never using for #2. I believe this is what's setup on my boat, but I'm thinking I need to add a pump so #2 is ok to the tank. The sewage holding tank is in the bow and its metal from what I can see. I have a Y currently not functional to the through hull out and that's also frozen in closed position (to be fixed at hull out). Its all pointed in the tank direction right now. My feeling is the tank is where I need everything to reliably end up.

No #2 on the boat in a long time - at least 5 years since before I owned it and don't plan on it until I get things sorted out. I don't know what would happen if the heads were used for #2, and I don't want to find out until I know where and how stuff will move. A test poo like substance I can test it with might be a first step? No smell what so ever but guessing there will be some when I open thing up :D.. Plumbing all looks solid no leaks and its run well. Both heads are new and are push/pull pump to flush work good for liquids right now.

I really don't know it the push pump on the heads is all that's needed as I've never tried. I'm looking for a two head diagram on how it should be setup with a macerator and without. Does anyone have something they can post or advise one where the pump should go, or advise if you think I should not need one and just let it fly.

Seems to be a good topic for my first thread :eek:

Thanks
CC
 
Need way more info and pictures.

What brand and type of heads do you have?

When was the last time they were rebuilt?

What condition is the metal tank in?

Metal holding tanks tend to be a problem.

What condition are the hoses in?

Etc., etc.
 
Metal holding tanks don’t tend to be a problem, they are a problem. Only a question of time before they corrode through. I would replace it before it starts leaking. Less of a mess that way.
 
CeC I did a complete rebuild of my entire system 3 years ago took out everything and replaced with new heads lines macerators vents and tank
 
When replacing a metal tank in the bow if the discharge is above the water line , no pump will be required.

Gravity is your friend , if the tank is high enough.

Toilet manual or electric pumps usually break up #2 as they flush so the stuff will go thru a line.

KISS really counts in waste plumbing as the hoses will stink after a while and need replacing.


Discharge pumps seem to last longest with least hassle if installed low so are wet at all times and push the waste rather than suck it out.
 
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Thank you everyone. FF That's really what I was wondering seems like a lot going on with the new heads push pull action lots of flush out pressure. From what I can tell the tank is above the waterline. As for the metal tank it looks ok, but I hear what you guys are saying. I think I need to remove the flooring in the bow to get the tank out (bigger project), so I need to look into that.


The lines are in great shape on the outside anyway all connections are solid zero evidence of the connections or hoses ever leaking. Previous owner replaced the heads the one in the bow cabin has never been used other then to test it - not sure of the brand but will check when I take some photos to post. Going to put my snake cam down under the tank and have a good look. Suspecting they rust from inside, so Ill look in there as well - that should be fun.


Also I need to get the Y valve replaced, so at that time I will snake cam the inside of the lines a bit too check them. This is not a live aboard so my goal is to have it functional for the occasional few day trip or emergency needs when out fishing. I may keep the steel tank for a while pending my full inspection.


Pics to come


Thanks all
CC
 
As others have already recommended, replace the tank. Urine is so corrosive that the average lifespan of any metal tank is only about 10 years...and they typically start to leak at a seam or a fitting within 5 years. Meanwhile the bottom is turning into a colander. There is no tank product that can prevent it...neither will frequent pumpouts and rinsing. The first leak is always only the FIRST leak...it's more likely to happen while the boat sits between cruises than while you're aboard, and it's your nose that will let know it's happened. It's not likely to be catastrophic, but even a small sewage leak creates a stinky mess. Seamless rotomolded polyethylene is the recommend water and waste tank material.

Ronco Plastics Ronco Plastics marine Tanks (no relation to the VegoMatic Ronco) is your best source for a tank. They make TOP quality thick-walled water and waste tanks for a very reasonable price and have more than 400 shapes and sizes, over 100 of which are non-rectangular, and they install fittings in the sizes and locations specified by the customer when they make the tank.

The apparent condition of a hose isn't the only thing to consider...age matters. 10 years is the average working life of any hose because rubber and plasticizers dry out over time, making the hose hard, brittle and prone to cracking. They should all be replaced if anywhere close to 10 years. Waste and sea water can permeate inexpensive hoses very quickly, causing 'em to stink.

There is absolutely NO reason to avoid putting solid waste in a holding tank. Solid waste is 75% water..even a manual toilet breaks it up enough to let it dissolve in the tank within hours. The right tank product along with sufficient venting to keep the tank aerobic will prevent odor.

I'll be glad to help you get everything sorted out to let you end up with a trouble-free, odor-free system. Meanwhile, you might consider checking out the link in my signature...you'll find useful information there.

And btw...welcome the forum!

Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
 
Peggie thank you so much! I see a tank in their catalog that looks just about the size of the one that's in there and its not that much. Going to have a good look and take some pics. Hopefully I can get the existing tank out without too much demo. I know the hose for at least part of the system is new, but Ill have a look at the run from the aft head as that's older and the to tank run will need replacing I'm sure. While I'm digging in Ill do it right. I guess the good news is there's no odor at all right now, and my focus is on keeping it that way.


Thanks again
CC
 
You're welcome to give me a shout via private message if you have questions or issues that require discussion in more detail than is practical in a forum.

Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein
 
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Welcome CC to TF!! Listen to Peggy she IS the poop expert....
 
I’ll be at the boat today going to get some pics and look in places I haven’t to see what’s there. I will post back after.
 
Tank looks like it’s the origonal and it’s fiberglass. What a mess. I have my work cut out for me literally. It appears so far that the inlet and outlet are at the bottom of the tank.

The hoses in there are bad. Going to be tough to get the tank out without a mess. Thinking I’ll cut the hoses in the engine room up top, plug them well and pull them out through the bulkhead when I take the tank out of the bow. I don’t think there’s any way to get the tank completely empty, but I’ll do my best with a shop vac first. If the tank breaks when I pull it out I’m in deep poooh from the smell around the tank. Going to replace everything but the heads. I’m experienced working with pvc and I see some on here are using that. Are there negatives to using pvc pipe? Seems vibration might be a concern? Maybe hose to pvc connection where needed might cause un necessary inside edges impeding flow?

CEC
 
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