Holding tank will not pump out

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Bridgeman

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I overflowed toilet holding tank through breather by mistake. When tried to pump out with jabsco on board it will not discharge. Pump is working and sounds ok. I thought breather may have clogged up causing a vacuum, but on opening pump out screw plug on deck to allow air in it still will not pump out. Any suggestions what to do to sort it out?
Thanks.
Neil
 
Thanks JRudge. Yes valve is open and everything was fine before I overflowed tank. Is there anything you can put in tank to help flush out or is it just a fresh water flush down the shore discharge point?
Rgds Neil
 
Could the diaphragm have failed in the pump, so it would still run but not pump out? Can you see a pulsing affect in the outlet pipe between pump and sea cock which would suggest the pump is working properly and the pipe or sea cock is blocked? If you can, then it could be scale from the inside of the pipes which has broken off and blocked the seacock. This is easily checked by taking the pipe off the seacock, though it's not a pleasant job of course!
 
Does it sound like the pump is struggling (blockage) or free running ( Broken pump)?
Is it a macerator pump or diaphragm pump?
Macerator could have something around splines.
Diaphragm pump could have something stopping non-return valves from closing.
 
Nick_H said:
Could the diaphragm have failed in the pump, so it would still run but not pump out? Can you see a pulsing affect in the outlet pipe between pump and sea cock which would suggest the pump is working properly and the pipe or sea cock is blocked? If you can, then it could be scale from the inside of the pipes which has broken off and blocked the seacock. This is easily checked by taking the pipe off the seacock, though it's not a pleasant job of course!
Click to expand...

Cheers Nick. I will check it out tomorrow when back on boat.
 
If you are on a pontoon with water... close the outlet valve on your hull fitting and remove (carefully as there may be pressure :disgust:) the pipe from the fitting. Stick a hose into the end and back flush to remove blockage. Not a nice job and we only ever wee in ours :ambivalence:

ps. a pair of mole grips to squash the pipe between the pump and the skin fitting helps reduce and spillage but remember to remove when you start back flushing and re apply when you finished. Save a lot of mopping up...
 
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I had a similar problem this spring where the pump was going but sounded stressed and didn't empty the tank.

I removed the hoses and disassembled the pump to reveal the macerator 'impeller' and discovered a, ahem, fabric sort of thing tangled around it... Problem now solved.

Just remember to close the seacock before removing the outgoing hose, you'll save a lot of time cleaning up. About an hour and a half in my case...
 
Thanks Kev B and Scubaman. Will add to my list. I will let you know outcome. We have pump out facility and water on the pontoon so not a problem.
Rgds
Neil
 
On my current boat the tank would not pump out when I took ownership.
After the dealer fixed it but it still didn't work, I rolled up my sleeves and got stuck in (the fact the boat was a ex-demonstrator made it all the worst, swishing around in the dealers sh*t)
I eventually found the 2 way valve was in the wrong position, so when the pump was started it sent the sh*t to the deck fitting (which was obviously closed) the resultant pressure build up turned the joker valves either side of the pump inside out, so although the pump appeared to operate correctly it was unable to pull/push against anything.
 
I also had a similar problem at the beginning of this season following a strip down of the pump for maintenance. The pump was running but nothing was coming out of the discharge pipe. All that the technician did was to remove the pipe to the holding tank at the pump end and fill it with some water to prime the pump. Its possible that might work for you
 
The fact you filled the vent pipe is likely a red herring. Your pump out just isn't working. That means a blocked pipe or a defective pump. Can suggest pump remedies if you tell us what sort of pump it is
 
Sishoe said:
On my current boat the tank would not pump out when I took ownership.
After the dealer fixed it but it still didn't work, I rolled up my sleeves and got stuck in (the fact the boat was a ex-demonstrator made it all the worst, swishing around in the dealers sh*t)
I eventually found the 2 way valve was in the wrong position, so when the pump was started it sent the sh*t to the deck fitting (which was obviously closed) the resultant pressure build up turned the joker valves either side of the pump inside out, so although the pump appeared to operate correctly it was unable to pull/push against anything.
Click to expand...

That was a pain. Mine as been working fine until I overfilled it.
 
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