Head holding tank (or somewhere else in head system) "might be" slowly leaking

340DA

Member
Jul 21, 2008
365
LI Sound
Boat Info
2000 Sundancer Sport Cruiser
Engines
454 Mercruiser w/Bravo III Drives
On my 2000 340 Sundancer I have been noticing that the bilge has some brown water in it.

It is not a lot of brown water but enough to make me begin to think that something is wrong. It would almost appear that there may be a slow leak/weeping that is coming out of the holding tank, or from some other component part in the head system, and it is collecting in the bilge.
I have flushed the toilet and I have watch the system operate and I do NOT see any visible signs of leaking/weeping brown water into the bilge. Thus, I'm thinking it is a slow process...

The vacu flush system is working just fine. The toilet works fine. When the water collects over a few weeks, I flush it out with a hose. I am not talking about a lot of brown water, but enough to make me want to address the "issue". This is the 1st year I've noticed this.

Any thoughts/suggestions/fixes??????
 
I had exactly this problem last season. Most noticeable though was the smell. If you don't have a fowl odor, it's possible you have a different source of "brown water."

Replaced my holding tank this past winter.

There are metal releases in the bottom of the tank that have a tendency to slowly rust and decay. Note the dark patches near the top and bottom corners in the attached pic.

It wasn’t a fun job. Had to remove several components of the starboard engine to make enough room to remove and replace the tank.
 

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When the tanks were made (newer design fixes the problem), there was a problem in the casting of the tank. The part of the tank "feet" (in each corner) that would be used to hold and remove the tank from the mold was poorly cast and the plastic would crack and leak over time.

Before you condemn it, though, thoroughly clean around the tank and the "shelf" it sits on. Then stuff/tape some paper towels around the entire bottom perimeter. If it's leaking, the paper towels will show evidence of it.
 
I had a rainwater windshield leak that passed along some inner wall exposed fiberglass. That turned it brown by the time it got to the bilge. You may have a hull window or deck opening leaking.
 
I would think you could tell by the smell.
I get dirty water in the bilge if caught in a rain.
 
On my 2000 340 Sundancer I have been noticing that the bilge has some brown water in it.

It is not a lot of brown water but enough to make me begin to think that something is wrong. It would almost appear that there may be a slow leak/weeping that is coming out of the holding tank, or from some other component part in the head system, and it is collecting in the bilge.
I have flushed the toilet and I have watch the system operate and I do NOT see any visible signs of leaking/weeping brown water into the bilge. Thus, I'm thinking it is a slow process...

The vacu flush system is working just fine. The toilet works fine. When the water collects over a few weeks, I flush it out with a hose. I am not talking about a lot of brown water, but enough to make me want to address the "issue". This is the 1st year I've noticed this.

Any thoughts/suggestions/fixes??????
I agree with R and R , you would notice the fowl smell first if it was coming from the tank.Start looking else wear !
 
This is all good information.
FYI: I do smell a "smell" from the brown water. That's why I suspect it is somehow dripping/leaking from the holding tank????

As I said, it is slow leak, thus the amount of brown water builds up slowly over time. I am able to flush it away with a hose. And, we rarely use the head for "solids". Only "liquids"

BUT, to ZZ13's point, the port side hatch window in the head does leak in rainstorms. That's a possibility of the source?
 
Where can I buy a new holding tank for replacement?
 
I guess you confirmed it's leaking?

Talk to Northeast Marine Sanitation - they're in your neck of the woods and really know their... ummm... well, I'm sure you can figure out what word finishes my sentence!
 
Deck leaks produce brown water from the rotting balsa core. The fungus is brown.
Garwood 003.jpg
 

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