Manual holding tank pump-out clogged

[peghall]

Can you clarify the dinghy-pump solution? It sounds like this might be a decent idea, but do I need to be worried about the manual membrane pump that is between the through-hull and the holding tank when pumping air backward through the line?

I'm not sure it's possible to force air past a pump in the discharge line. However, there may be a product that can dissolve the sludge...I know the owners and have emailed 'em to find out, and if so, how much to use.

What is a joker valve?

It's a one way valve in every manual and electric toilet...a rubber cup shaped doodad that has a slit in the bottom with "lips" on the outside of it that's installed in the toilet discharge fitting (the one the toilet discharge hose connects to). It doesn't have anything to do with the holding tank or pumping out a tank.

[Kenomac]

Why not just remove the inspection lid cover to your holding tank and lift up the pumpout tube slightly to get it off the bottom? You'll probably then be able to just pump it out using your manual pump. Then deal with the sludge.

[Ryban]

I removed the hose that leads from the toilet to the U-bend just before the holding tank, but that also wasn't the issue -- so it can't be the joker valve upstream of this portion.

The holding tank is hidden behind some wooden panels that are screwed in, but I'll see if I can take some screws out and gain access to the tank and see what I'm dealing with.

[Kenomac]

When you establish that sludge is the issue, get back to me and I'll suggest an easy way to deal with it.

[ramblinrod]

Originally Posted by Ryban

I believe there's a clog between my manual pump out and the holding tank. I say this because I can flush the toilet no problem, but I can't pump waste out through the seacock. I can perform one pump with the handle, but after that, it the handle won't budge much, and I can hear the sound of hissing air when I try to force it. My guess is a vacuum is forming, making it all but impossible for me to pump.

The only thing that has been put down the toilet is digested food, and small amounts of toilet paper.

Am I wrong to be hopeful that time will resolve this problem on its own? I did pour some vinegar into the toilet and flushed it, hoping it would help break down the clog.

In general, switch to dry bowl operation. If pump can't overcome, it is
Usually a closed discharge valve. If pumps fine, switch to wet bowl mode, if
Won't pump it is usually a closed seawater seacock.

Beyond that you need to help us out with your plumbing configuration.

1. All toilet contents get pumped to tank. Separate pump from
Tank to overboard discharge seacock.

2. Toilet contents pumped to wye valve, that is directed to tank or
Overboard discharge seacock.

[ranger58sb]

Originally Posted by Ryban

I removed the hose that leads from the toilet to the U-bend just before the holding tank, but that also wasn't the issue -- so it can't be the joker valve upstream of this portion.

As Peggie suggested, the joker valve probably isn't related to your issue...

But FWIW, I'd have expected your joker valve to be right at the junction of toilet and discharge hose. The flange on the joker valve would likely be acting like a gasket between toilet and hose.

Originally Posted by Ryban

I believe there's a clog between my manual pump out and the holding tank. I say this because I can flush the toilet no problem, but I can't pump waste out through the seacock. I can perform one pump with the handle, but after that, it the handle won't budge much, and I can hear the sound of hissing air when I try to force it.

Originally Posted by Ryban

The seacock can of course be closed, and there's a vent for the holding tank, but the deck-level pump out was removed a long time ago.

Have you verified that the handle on the seacock actually opens and closes the valve, so waste can exit via the thru-hull?

-Chris

[Ryban]

Originally Posted by ramblinrod

In general, switch to dry bowl operation. If pump can't overcome, it is
Usually a closed discharge valve. If pumps fine, switch to wet bowl mode, if
Won't pump it is usually a closed seawater seacock.

Beyond that you need to help us out with your plumbing configuration.

1. All toilet contents get pumped to tank. Separate pump from
Tank to overboard discharge seacock.

2. Toilet contents pumped to wye valve, that is directed to tank or
Overboard discharge seacock.

The issue isn't anywhere between the toilet and the holding tank, as I disconnected that hose, and still wasn't able to operate the manual pump out.

The system is simple. The toilet pumps into the holding tank, the holding tank has a hose to a deck vent, and one other hose at the bottom that gravity feeds through a large membrane pump and through a seacock. Generally I pump waste out any time I'm at sea, which is on a weekly basis. So I'm a bit surprised that there's a blockage or excessive waste build up at all.

[Ryban]

Originally Posted by ranger42c

Have you verified that the handle on the seacock actually opens and closes the valve, so waste can exit via the thru-hull?

I will check this next, but I do believe it is operating correctly. Then again, it's the most used seacock on the boat, so that either means it's the most likely to be functional, or the least likely.

[ranger58sb]

Originally Posted by Ryban

I will check this next, but I do believe it is operating correctly. Then again, it's the most used seacock on the boat, so that either means it's the most likely to be functional, or the least likely.

We had a blockage on our fishbox pump-out. The macerator would run, but the box wouldn't empty. Replaced the macerator, no change. Eventually we discovered we simply had years of fish bits, especially scales, clogging the thru-hull. Easy enough to clear from above, but not pleasant... and your situation would be worse.

Anyway, in our case we could (eventually) tell the valve body was working... but the symptom was as if the thru-hull was closed... and that'd perhaps be the same symptom if the valve handle isn't actually opening the valve...

Or if you have a clog within the valve body/thru-hull, for that matter...

-Chris

[ramblinrod]

Originally Posted by Ryban

The issue isn't anywhere between the toilet and the holding tank, as I disconnected that hose, and still wasn't able to operate the manual pump out.

The system is simple. The toilet pumps into the holding tank, the holding tank has a hose to a deck vent, and one other hose at the bottom that gravity feeds through a large membrane pump and through a seacock. Generally I pump waste out any time I'm at sea, which is on a weekly basis. So I'm a bit surprised that there's a blockage or excessive waste build up at all.

Does the pump have a dry bowl / wet bowl switch (valve)? If
so, switch to dry bowl. Does it pump? If no, look for discharge blockage. If yes, switch to wet bowl. Does it pump? If no, look for seawater inlet blockage.

PS, it would help a great deal if you advised the make and model of head configuration.

Based on your info / responses to date, my best guess is you are in wet bowl mode but the seawater inlet seacock is closed, so the pump can't be operated on the first auction stroke.

[ramblinrod]

Originally Posted by Ryban

The issue isn't anywhere between the toilet and the holding tank, as I disconnected that hose, and still wasn't able to operate the manual pump out.

The system is simple. The toilet pumps into the holding tank, the holding tank has a hose to a deck vent, and one other hose at the bottom that gravity feeds through a large membrane pump and through a seacock. Generally I pump waste out any time I'm at sea, which is on a weekly basis. So I'm a bit surprised that there's a blockage or excessive waste build up at all.

Whoops, I may have misunderstood.

Please verify:

1. The head pump is working fine, pumping effluent to the holding tank under all conditions.

2. The secondary overboard discharge pump is not functioning at all.

If 1 and 2 are correct, then the most likely culprit is that the overboard discharge seacock is not open. If that is not the case, the second most likely culprit is a blockage on the suction side of the pump, somewhere between the tank and pump.

Rarely will an effluent blockage go through the pump and not out the discharge unless the discharge seacock is not open as the pump will develop a lot of pressure as long as there is fluid flow possible from the suction side.
Flow

[jamhass]

Can you pump out from the deck access, say at a marina pumpout station? If so, the vent is likely OK. If not, recheck the vent -- it could be blocked anywhere along that line, including the fitting where the vent connects to the holding tank.

If you CAN pumpout from the deck, then the problem must be somewhere in the pumpout plumbing: the pickup, hoses, pump or seacock.

[Bleemus]

Originally Posted by jamhass

Can you pump out from the deck access, say at a marina pumpout station? If so, the vent is likely OK. If not, recheck the vent -- it could be blocked anywhere along that line, including the fitting where the vent connects to the holding tank.

If you CAN pumpout from the deck, then the problem must be somewhere in the pumpout plumbing: the pickup, hoses, pump or seacock.

He does not have a deck pumpout.

[jamhass]

Originally Posted by Bleemus

He does not have a deck pumpout.

Doohhh ... missed post #3 ...

[Ryban]

Good news everyone!

After several hours, I was able to resolve the issue, but it wasn't pleasant.

I first tried the simple things, like trying to resolve the plug from above, and by trying to pump air into the seacock with a dinghy pump in hopes of dislodging the clog. These attempts were fruitless.

Then I accepted I would have to get dirty. I started by disconnecting the pipe closest to the diaphragm pump -- very slowly. Once I realized that this broke the vacuum, and brown water wasn't flooding out, I knew the clog was upstream. I continued like this until I got to the elbow just below the holding tank. This is where the clog was, and it had backed up into the holding tank itself. The clog seemed to be chips of some hard matter -- perhaps calcium build up that had broken off the sides of the pipes.

Once I cleared the clog in the elbow, I very carefully poked a zip tie up into the clog in the holding tank until it started dripping. Once it was dripping, I re-assembled all the piping, and was able to pump out the clog without getting poo everywhere.

It wasn't fun, but it could have been worse.