Water Leak- fresh into holding tank??

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BellaDonna

Veteran Member
Joined
Aug 21, 2012
Messages
68
Location
USA
Vessel Name
BELLADONNA
Vessel Make
34' MAINSHIP HARDTOP TRAWLER
I am totally confused. I have a Mainship 34 hardtop trawler 2008 twin 240 Yanmars. The waste tank seems to be filling with fresh water. The gage indicates filling after only minimal head:confused::confused: use. We pumped it out and within 24 hours of very little use it was registering full again. I found 2 gals or more of fresh water on the head floor and at the foot of the master bed.

After looking under the steps at the water lines and tank I found no trace of water. Under the bed I found traces of a condensate leak from the a/c unit but this appears to be old and would be salt water not fresh water.

When pumping out the waste tank it seems to take longer than usual.

Does anyone have any ideas on how I could be leaking fresh water into the waste tank or onto the floor of the head when the pressure is on to the water? Thanks, Belladonna
 
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Sounds like you have a serious leak somewhere. Check to see if the fresh water pump is cycling even though you do not have a faucet running. Hard to tell if the waste tank filling up is related to the water on the floor.

Somehow, you need to look carefully at all the water connections in the area of leakage. I like to use pieces of paper towels warped around hose connections to see if they get wet. If so, that's the source of leakage.

One thought on the waste tank filling up without use, is check the thru-hull seacock for the overboard discharge if it is open. If it is open, you could get water from the outside going through the macerator pump.

Ron
 
You could have a head that is leaking in the area that allows water to flow into the bowl and somehow the vacuum pump is sucking the water out of the bowl and into the holding tank.
 
Are you at the dock hooked up to city water under pressure?

If so, disconnect the water supply and operate for a period on your fresh water tank and pump.

If not, do you hear the fresh water pump running periodically without apparent use?

Do you have a fresh water flush in your head?

Is this a new-to-you boat? If not, is this a recent change?
 
Couple months back my fresh-water toilet ran over, but the water overflowed on the floor rather than going to the black-water tank. Fortunately, the valve self-corrected before I attempted to replace it, and there was a drain in the toilet-room floor.

img_156572_0_8c1730137e89ce8b4476ee06e9a7f359.jpg
 
Couple months back my fresh-water toilet ran over, but the water overflowed on the floor rather than going to the black-water tank. Fortunately, the valve self-corrected before I attempted to replace it, and there was a drain in the toilet-room floor.

img_156603_0_8c1730137e89ce8b4476ee06e9a7f359.jpg

And how does this help the OP?

+1 on the open seacock as it has happened to me on my previous boat. For fresh water to enter the holding tank, your fresh water flushing head would have to be failing in a unique way.
 
On a few occasions I've found a speck of dirt on the seal in the fresh water solenoid valve that flushes the forward head. Since I have a vented loop in the discharge line, the bowl fills up (with clean water) and overflows into the floor drain for the in situ shower. The shower sump pumps it over the side. Anyway, the leak is very slow...takes a few hours to fill the bowl , so I typically catch it before it's full. But I'd never notice it if not for the vented loop. The Jabsco valves (on our Raritan) heads can be disassembled and cleaned. It normally happens right after I initially turn on the fresh water pump, so there must be tiny specks of dirt that are getting past the fresh water filter. Never had it occur when hooking up water from shore.
 
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Sounds like you have a serious leak somewhere. Check to see if the fresh water pump is cycling even though you do not have a faucet running. Hard to tell if the waste tank filling up is related to the water on the floor.

Somehow, you need to look carefully at all the water connections in the area of leakage. I like to use pieces of paper towels warped around hose connections to see if they get wet. If so, that's the source of leakage.

One thought on the waste tank filling up without use, is check the thru-hull seacock for the overboard discharge if it is open. If it is open, you could get water from the outside going through the macerator pump.

Ron[/QUOTE

Ron, Yes I am uncertain if my head is fresh water or sea water.
Naturally I assumed it to be sea water but I'm not 100% sure of that.
The thru-hull seacock is closed. Thanks for the info, keep me posted if you think of any other possibilities. Donna
 
Are you at the dock hooked up to city water under pressure?

If so, disconnect the water supply and operate for a period on your fresh water tank and pump.

If not, do you hear the fresh water pump running periodically without apparent use?

Do you have a fresh water flush in your head?

Is this a new-to-you boat? If not, is this a recent change?

Fly Wright...The leak on the head floor occurred when we were not hooked to the dock's water. Didn't notice the pump cycling. I am not sure if it is a fresh water flush, I assumed it was sea water. We are currently hauling the boat to try to determine the leak. Perhaps it is something to do with the toilet or shower. thanks for your reply...Donna
 
... qualified surveyor?

Not sure an IACS or flag surveyor would be interested but you can get an alphabet guy to test it ... taste test that is.
 
Fresh or Sea??

Can't believe it is fresh water but will definately find out. Boat has been hauled out and is at the marina. Unfortunately, I do not fully trust Mainship's owner manual. I have found many discrepancies, it could have been helpful. Thanks again...Donna
 
I have found a leak from the holding tank onto the ground. The boat is out of the water.
Could the valve on the h.tank be allowing seawater to enter the tank? Perhaps this is the answer to one of the problems. Let me know your thoughts. Also can you tell me if the fiberglass on the dark blue sides is a paint or is the color in the fiberglass. Do the Mainship 2008's (dark blue) have an additional clear coat. Any info. on the glass would be helpful as I need to touch up a few scratches. thanks again....Donna
 
if your 34 is anything like my 390, make sure your macerator discharge valve is closed. On the 390 the holding tank is below the water line and the macerator discharges below the water line. when your sitting still, the water will find its own level which is about half full. If you run with that valve open you are forcing sea water into the tank and it will fill completely and find any way it can to come out: vent line, toilet, etc
John
MS390
 
Yes that well may be one of the problems. Sounds very logical. I'll have the macerator valve checked. Many thanks.....Donna

Any ideas about the gel coat color? Is the color painted or is it in the gel coat finish?
 
It is in the gelcoat finish; not paint. By the way, I discovered the issue about the macerator valve the same way you are. Raw sewage on the floor of the head, in the bilge and on the side of the boat near the vent. the reason why it takes you so long to pump out is with the discharge valve open you are sucking all of the water in through the discharge line through the pump and back into the tank as you're trying to empty it
John
 
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Do you know what the gelcoat is called or how to repair it?

We found fresh water (2 or 3 gals) on the head floor, I believe that this is another problem. The filling of the waste tank puzzled me. It does make sense that it is the macerator valve. Is there another valve? I found the raw water leaking from beneath the hull on the mid ship stb. side. The boat has been hauled. Still need to find the source for the fresh water.. thanks john.......
Donna
 
sounds like it is all the same issue. You say your head discharge from the macerator is on the starboard side beneathe the boat. mine is port side. With the macerator valve open and the boat moving through the water, sea water is forced into the holding tank through the macerator; it then fills the tank very quickly. Once the tank is full the water has nowhere else to go so it comes out the vent on the side ove the boat. The vent line is very small so not much can come out. the water looks for the next easiest place to come out and that is back through the line to the toilet. It fills the toilet and then sloshes out onto the floor. Once you stop the boat the water finds its own level; the toilet drains back to the holding tank then the holding tank drains back out through the bottom of the boat until everything, toilet, holding tank, lines, etc reach sea level. Close the valve and the problem goes away. You will need to replace the joker valve on your flush assy (I have an electric head. If yours is electric the joker valve is the rubber flap about 3" long inside the hose at the pump discharge). Forcing the water back through the joker valve probably damaged it. 390's have a warning right on the breaker panel stating to make sure the macerator discharge is closed. The coast Guard says it has to be closed for environmental reasons, but Mainship put the warning on there to stop this problem from happening.
John
MS 390
 
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