Bilge Pump Advice needed

[jpendoley]

I am losing my mind with a bilge pump project-maybe you all can save my sanity. I have a DEEP bilge-like 48" deep. I have a great high capacity water pump that is alarmed and wired to a counter-works fine. I am trying to install a nuisance water pump to remove rain water that enters the bilge via the stowaway mast. Rain runs right down the large mast slot and drains into the bilge. I installed a mast boot, minimally effective and there is always the drip from the stuffing box. Eventually I will buy or make a "dry bilge" diapragm pump and tubing solution to get the last drops, but first I have to get the lower capacity nuisance pump to shut off aft?er it is activated by the water witch sensor.
The nuisance pump has a check valve installed right after the pump to prevent water in the long hose line from draining back after the pump shuts down-seems to work well (kind of clunky-bought from a plumbing supply store but has low resistance which I would think is a prerequisite) BUT the water that remains is enough to trigger resistance on the nuisance pump impeller such that the pump thinks there is enough water to require pumping. I'm talking like a 1/2" of water. Result is the pump cycles on and off continuouisly and would drain the batteries eventually if left it unattended. The pump is a Johnson 1000 GPG pump-had the same problem with a Rule 500 GPH pump. Anybody got a model recommendation that would solve this problem?

[Kokanee]

One possibility is to modify your bilge shape so it has a small sump area just big enough for your bilge pump and water witch.
The total volume of water remaining will be much less and it shouldn't slosh around as much setting off another run cycle.

[steve77]

For a pump to get rid of nuisance water - A diaphragm-style pump will be probably be more effective than a centrifugal pump for emptying the water from the bilge. Doesn't the water witch switch allow for several seconds of running after the low water point is reached? If so, then the diaphragm pump will probably continue to pump the water out until your hose is dry.

I have installed Jabsco 50880 bilge pumps and am very happy with them. The larger centrifugal pumps are mounted higher in the bilge and should never see water unless there is a real problem.

Cheers!

Steve

[Lepke]

One solution is to install a 2nd small pump using the current sensor and send that water to a shower sump. Install a 2nd float sensor at a slightly higher level for the existing pump. I use a Whale pump that gets almost all the water and has a built in rubber check valve.

I also have a deep bilge of about 4+ feet and that's how I handle it. I either have to crawl into the bilge or do a hand stand to get to the very bottom.
https://www.youtube.com/watch?time_c...ature=emb_logo

[jpendoley]

What I don't understand is it the pump remaining on after the water level drops below the sensor because the sensor measures increased resisitance due to residual water-or does the pump have the intelligenge that senses the residual water? I had assumed it was logic in the water witch, but now I am wondering if it is in the pump its self. and if I went with a diaprgam pump like the Jabsco 50880 can it be mounted remote to the bilge or does it need to sit in the bilge? Given that the bilge is long and narrow, it could be convenient to leave the sensor in the bilge and remote mount the pump-if a diaphragm pump could handle that....

[rslifkin]

Some sensors do have a timer to run the pump longer when the water drops to try to get the bilge closer to dry. It looks like the Water Witch switches do have about a 15 second off delay (and a shorter on delay to prevent accidental short cycles if the water is sloshing a bit).

Diaphragm pumps can be remote mounted, they'll lift water a few feet with no problem.

[Jammer]

Originally Posted by jpendoley

Anybody got a model recommendation that would solve this problem?

Move the switch an inch higher.


You do not get an award for having a dusty bilge. If you care enough you can vacuum it out with a wet-dry vac before the Bilge Committee arrives for an Inspection.

[jpendoley]

The bilge committee aside, moving the switch doesn’t help. Pump runs because of residual water/the signal is higher electrical resistance based on pump trying to remove residual water.
The merits of a dry bilge are legion. It’s aspirational😁

[jkishel]

Originally Posted by jpendoley

The bilge committee aside, moving the switch doesn’t help. Pump runs because of residual water/the signal is higher electrical resistance based on pump trying to remove residual water.
The merits of a dry bilge are legion. It’s aspirational😁

You could add a mechanical float switch on the auto wire to the pump. That will turn off the pump when the bilge water level is down to 1/2 inch or so and repower the pump when the bilge level rises, allowing the pump to turn itself on.

[Jammer]

Is the switch built into the pump? Get a separate one.

[DeValency]

Originally Posted by Jammer

Is the switch built into the pump? Get a separate one.

Water Witch sensor is a standalone device. The OP says the water level is below the sensor while the pump continue working?

One issue can be with some moisturized mud/dirt/salt on the sensor that creates a shortcut between the electrodes. I would try to clean and dry the sensor really well and test it again. If that's the case, the bilge probably need more frequent cleaning (ShopVac is your best friend on board!).

Centrifugal pump will never remove water under about 20-30mm above the impeller. A second diaphragm pump (maybe with a timer?) can theoretically drain the bilge to a minimum of say 5mm or so.

[jpendoley]

It's a bit embarrassing that I can't figure this out-I rebuilt the old diesel and sucessfully-but a little thing like a $30 pump has got me flummoxed..
The sensor is an inch above the pump-both fastened to an epoxy coated plank. All electrical connections dry and far above the water level. If I lift the pump and sensor clear of the water and throw the switch, the pump cycles 3x for one or two seconds then shuts down. Put it back in the bilge where there is water, throw the switch and it cycles 3x briefly-then runs continuously until the water drops below the sensor. It shuts off then starts back up again and runs continously no matter how little water remains. Wiping the sensor clean makes no difference and a shop vac would be pointless as I'd have to do that after every rainfall.

This happens if the sensor is within three inches or one inch of the pump impeller. The pump evacuates water down to about 1 " and can't take it any lower. 1" is a lot of water in a bilge that is 3 feet long and 6 inches deep....
It could be an intelligent pump or it could be an intelligent sensor (water witch 101). Next step is to bypass the sensor and see if the pump does the same thing without the sensor in line. Back to the bilge....

[Calaban-Alleria]

Maybe try a solution like this:
https://lifeempirically.com/2018/03/...-bilge-system/


(Someone else posted this on another thread - I have not tried it)

[jpendoley]

Originally Posted by Calaban-Alleria

Maybe try a solution like this:
https://lifeempirically.com/2018/03/...-bilge-system/


(Someone else posted this on another thread - I have not tried it)

This is my next project-AFTER I get the damned pump to shut off

[Cadence]

I am not sure i understand the cause of the problem. If it is the sloshing of the remaining water. What about encircling the pump with a barrier and one opening enough to permit the pump out. It might stop a furling effect. A cut off plastic bottle of the right dia.?