Shower water pump does not entirely empty the drain

[sailinggeorge]

Hi, I just bought a pre-owned 479. The shower pump works, but there’s always about 1cm of water remaining over the drain. Same with toilets, I always get them half full with water after I pumped all out. Any suggestions?

[Zanshin]

I have the same problem, it empties all the way but when the pump turns off there's a bit of backflow into the drain. I have a rag that I use to wipe down the inside of the shower and use that to soak up the bit of water in the drain and wring it into the sink. It's not a solution, just a workaround... If I could access the drain hose I might put in a small joker valve, but haven't tried that.

[Mistroma]

I assume the toilets are manual Jabsco twist'n lock and there are a couple of things to try.

1) Always try to pump the bowl dry.
A greater pressure difference will help to close the joker valve if it isn't too old. This helps when the valve mentioned next is leaking.

2) Lock the pump handle fully down.
This pushes down on a flap valve that provides a more positive seal than the joker valve.

You probably need to replace some parts if the bowl still fills.

I'd start with the flap valve as it is meant to provide a proper seal and is a quicker, cleaner job. Just thoroughly flush with soapy and fresh water and undo screws at base of the pump body.

A new valve will solve the problem as long as the handle is locked down. However, the piston end will eventually put a small depression in the valve top and reduce the seal.

Not much help with the shower drain.

[tarn]

Hi I have the same problem with the shower drain. Mine empties the tray but then back flow from the pump occurs. I believe the problem is that the pump will pump fluids better than air. It won’t clear the waste water completely from the pipe and then gravity returns a little water back into the tray. Cheers Tarn

[virtualburton]

Hmm, I have. 2013 469 and my "gulper 320" pump empties the drain completely in both heads...

Maybe your pump diaphragm is worn or leaking a bit? The pump is located under the sink.

One thing I did is remove the 15 second timer relay and replaced it with a regular relay so I don't have to constantly turn the pump on and off.

I usually shower for a bit, then turn the pump on once there is a bit of water in the shower floor pan. Once I finish washing I let the pump run until the water is out of the drain then I usually dry off. While I am driving, more water will trickle down into the drain, so then I turn the water on again and use the wand to spray down the floor of the shower, Last I turn the pump back on for another 15 seconds or so and it will be dry in the drain.

Hope it helps.

[moonshadow]

My 2014 SO469 is set up the same as virtualburton’s boat and also pumps completely dry. The gulper pumps seem to do a great job. I’m not an electronic whiz so I still have the 20sec timer.