Grey water pump mystery

[jsmbythebay]

I have a Whale Gulper 220 grey water pump that pumps water from the shower pan out an above waterline through hull.

It was having issues pumping out in November, so I rebuilt the pump with new valves and seals and used a snake to ensure all hoses were free of obstructions in November.

Since then, it still sporadically continues to have the same issue where it can't pump water out. When I check the input tube, it seems to be pumping water back and forth.

I have now narrowed a fix down to where I remove the output tube from the pump, hear a "suction" sound (I believe the water in the input tube draining back into the showerpan), then hook the output tube back up. Voila, it starts pumping again perfectly.

Until it doesn't. And I have to do it all over again. Probably on a weekly basis almost.

The obvious problem would be something stuck in the input hose or input tube or floating around in the pan/container. These I have pretty much ruled out.

Any ideas?

Thanks in advance.

SV Abeona

[tkeithlu]

Two immediate things to check.

1, it sounds like you are losing prime to an air leak on the suction side. That would be particularly true if it has prime and then loses it.

2, possibly a leak in the pump diaphram.

Your new joker valves should have taken care of #3, leaking joker valves.

[a64pilot]

99% sure that pump is a diaphragm pump, and therefore self priming.
If it’s ever pumping water back and forth through the intake, you have a stuck open intake valve, exhaust pumping back and forth, a stuck open exhaust valve.

Maybe junk building up on the valves, do you have a good strainer before the pump?

[Northbound44]

This looks like an airlock.
Définition: An air lock is a restriction of, or complete stoppage of liquid flow caused by vapour trapped in a high point of a liquid-filled pipe system. The gas, being less dense than the liquid, rises to any high points. This phenomenon is known as vapor lock, or air lock.

Flushing the system with high flow or pressures can help move the gas away from the highest point, or a tap (or automatic vent valve) can be installed to let the gas out.

[Mediator]

Our grey water pump is different (a Rule) but we've had problems with the brass check valve (between the pump and through hull) jamming and blocking flow. Might want to give that a check if you have one.

[Smokeys Kitchen]

Originally Posted by a64pilot

99% sure that pump is a diaphragm pump, and therefore self priming.
If it’s ever pumping water back and forth through the intake, you have a stuck open intake valve, exhaust pumping back and forth, a stuck open exhaust valve.

Maybe junk building up on the valves, do you have a good strainer before the pump?

+1 on the strainer in place before the pump.

Ours requires fairly frequent service when we are out and using the shower regularly. Maybe once a week or so.

[jsmbythebay]

Thanks all.

I have been thinking it might be an airlock, but not sure how to diagnose or remedy. The input hose high point is above the pump that is mounted so that it pumps downward. Maybe the air lick is in that bend in the input hose?

It is s diaphragm pump and i believe self priming.

All vAlves and diagram were replaced in November.

There is not a strainer (nor a very easy way to put one in) but that might be part of the problem...

[Thumbs Up]

No joker valve in these pumps, just rubber flaps. Self priming too, no airlock. Some debris has to be getting stuck in the valve flaps, or the rubber is old. Could always add some inline check valves as a quick fix.

[Dockhead]

These are remarkably good pumps; I have one which is original to the boat and so 18 years old, and which is used very heavily, pumping all the boat's gray water including from a washing machine, except only that from the fwd heads. Considering I am more or less constantly living aboard for maybe 4 months a year, and have up to 6 or 7 people on board in summer, that's a lot of pumping. The original diaphragm lasted more than 10 years.


These pumps are powerfully self priming, so a small air pocket could not cause the OP's problem, in my opinion. When I've had similar problems it was a split diaphragm or an improperly fitted diaphragm housing. Just because the diaphragm is fairly new doesn't necessarily mean it's good, so I suggest check it carefully. I don't know what they are made of, but they are quicky destroyed by bleach -- don't ask me how I know


And +1 the previous post about debris in a valve -- check that too.

[Mike Banks]

My shower drained into a sump. wherein was a bilge pump float switch and a small Rule bilge pump which emptied the sump as needed through a siphon breaker to a discharge through-hull just above the laden water line. It was not possible with the vessel upright for any water from outside the vessel to get in because the siphon breaker duck-beak valve was well above the laden waterline.

The pipe leading into the sump from the shower passed through a large plastic mesh filter inside the sump, designed to trap hair and any other material likely to foul the bilge pump impeller. This I emptied from time to time--say once a fortnight whether it needed it or not. When the sump was full, which never happened unless one forgot to clear the filter, the shower simply did not drain. The water could not get out of the filter into the sump, which in any case was s fitted with a clip-down lid, to prevent it overflowing into the bilge should anything else such as the pump or float switch fail. Failure to drain was as good as any system of warning lights--and fail safe.

The bilge pump was a small RULE model and the float switch was similar, a switch I eventually replaced with a mercury relay float switch--but that was after YEARS of trouble-free live-aboard with two people useing it at least once daily--and I only ever replaced ONE small bilge pump in five years--cost of twenty bucks.

Now I am not suggesting a diaphragm pump is not suitable--I just think it is expensive overkill for this use. Diaphragm pumps are great for black waste that has been macerated--so I use them for holding-tank pump out at sea. Pump out in port was through a deck fitting for suction hose attachment.

[Dockhead]

Originally Posted by Mike Banks

. . . Now I am not suggesting a diaphragm pump is not suitable--I just think it is expensive overkill for this use. . . .

Diaphragm pumps have a lot of advantages in this application, which is why they are the usual choice. Grey water usually has different solids in it, if nothing else then at least bits of soap, hair, etc., and if used for kitchen gray water too as mine is, then much worse than that. They are strongly self priming. You might get some other kind of pump to work in this application, but I would not personally use anything but a diaphragm pump.


And the Whale 220 is a really reliable really good pump. Hardest working pump on my boat, yet the 18 year old original still going strong, only original pump on the boat (I'm on my third water supply pump, third main bilge pump, etc.).

[Quadrille in JB]

Dockhead,
I hope this isn’t too far off topic, but which water supply pump do you use? I never get over a year of life from my sureflo pumps.

[Dockhead]

Originally Posted by Quadrille in JB

Dockhead,
I hope this isn’t too far off topic, but which water supply pump do you use? I never get over a year of life from my sureflo pumps.

A year is far too little even if you are on board full time.



I had Jabsco and Sureflo pumps in the past. Now I have a Johnson washdown pump which I adapted in an emergency (anchored out far from civilization, and the Jabsco had a failure which could not be fixed with any of my extensive spares kit). I cut the regulator spring to reduce the pressure. Been working fine for 3 years. My impression is that the Swedish made Johnson pump is quite a bit better made than the others. It also has a nicer, smoother sound.

[Quadrille in JB]

Dockhead,
Thanks, I’ll order a Johnson aqua jet pump today. Prices aren’t any higher than the ShureFlo pumps.
Windchime in FP

[TedPercle]

I had the same problem on my Meridian. I found that the discharge side of the pump was missing a rubber check valve. problem was solved by replacing the check. Hope this helps.