Cal 2-29 Bilge pump cycling

[TrentePieds]

Nylajo:

I'm just up the road from you, and it rains just as much there :-)!

If there is one thing you don't want to have happen, then it's freshwater — rainwater or smelt water from snow on deck — finding its way below. Do taste the water to determine whether it's fresh or salty!

If it's leakage, whether it be fresh or salty, I really, really recommend that you do something about it before winter hits us.

The little bit of water in the bilge won't harm you or the boat.

Since your keel ballast is encapsulated, at least you don't have to worry about keel bolts being damaged by the water :-)

TP

[Don C L]

I have a couple of these in case I ever need to reach down behind the water tank in my encapsulated keel. So far it's still dry. You could empty the bilge in between rain events maybe? I'd try to track down that leak too.

[GordMay]

Originally Posted by nylajo

The 5/8” hose from the pump to above the waterline still holds more the the bottom of the bilge

I'm confused - what am I missing?

Ten feet of 5/8" diameter hose can hold 0.159 US gallons of water. 2.5 Ft will hold 0.03975 gallons, or about 5 US fluid ounces.

[Jim Cate]

Originally Posted by GordMay

I'm confused - what am I missing?

Ten feet of 5/8" diameter hose can hold 0.159 US gallons of water. 2.5 Ft will hold 0.03975 gallons, or about 5 US fluid ounces.

And 5/8 inch is awfully small for a bilge pump outflow! OP, are you sure of that dimension, and what size is the pump?

Jim

[nylajo]

Actually the bilge hose is 3/4” and the pump is 360GPH.
The footprint of the bilge is 3 inches x 8 inches, the float sw. and pump are mounted on a piece of 3/4” UHMW so that displaces quite a bit of water.

[TrentePieds]

That makes the cross-sectional area of the hose 2.27 cm^2, IOW 14% more than the cross-sectional area of the 5/8" hose. Not even worth bothering about! Spurious accuracy is the bane of the sailorman, but on the other hand, as MySaintedMother usta say: "If it ain't quantified, it don't count!"

Given the configuration of the bilge, your standard "off the shelf" bilge pumps probably won't do the job. In addressing this "problem" knowing the flowrate of your pump won't do us much good.

Let us know the make and model of your pump and, if you are using a separate float switch, the make and model of it. Then we'll be able to help you far better.

A sketch of your existing installation would also help. It doesn't have to be fancy at all. It just needs to indicate the actual positions of pump and switch in relation to the bilge. Photos might also do the trick, but if you are not in the boat, just do a sketch on any old bit of paper, photograph it with your cell phone and download the pics to CF.

TP

[davil]

looks like you have the answer
post # 2

capt jgw
Registered User


Join Date: May 2015
Location: Muskegon, Mi
Boat: Columbia 36
Posts: 1,279
Re: Cal 2-29 Bilge pump cycling
I had a similar problem in my Columbia 36. One large bilge pump amidships with about 20 feet of 1 1/2" hose discharging out the transom. The hose contained enough water to cycle the pump when it drained back to the bilge and it would pump that same gallon or two of water back and forth all day long. My solution was to remove the big pump and replace it with a little one, 360gph as I recall, with as short a hose run as possible discharging amidships at the gunnel. Only a few ounces drain back, not enough to cycle the pump. The big pump with it's own float switch was put back in on a shelf about 4" above the little one. The little pump handled nuisance water and the big one was still there in case of more serious flooding, which never happened. An alarm on the big one would have been a good idea but I never got around to it.
capt jgw is offline

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more likely a new over the water line discharge thru hull ?

[wyb2]

Diaphragm pumps are their own anti-backflow valves. Combined with a sensor/switch that can keep it running for X seconds after the water is gone, it will purge much of the water from the hose as well.


https://defender.com/en_us/whale-gul..._wcB#493=19515

[massnspace]

You are overthinking this….you have a bad “NR valve”, as you have called it.

A properly-function anti-backflow fitting WILL NOT allow any water back, after it has passed the pumped water through initially. If it won’t allow any back through, then your bilge pump switch cannot be reactivated….

I think it is that simple….check (replace?) whatever you have that is allowing the water back into the bilge….and make sure that fitting is very close to the pump….just so any residual water between the fitting and pump (which WILL drain back in) will be a minimal amount…

[Scott Berg]

I've been installing bilge pumps for 40+ years; lots of the recommended options work but the best way is to have two (2) pumps. One centrifugal pump (the largest you can fit) AND one small diaphram pump (has built in check valves and pumps dry) at the bottom of the bilge. I like the Whale Gulper 220 with a good float switch independent of the centrifugal pump; YMMV

[capn ken]

Good morning , I have a cal 29 ,owned for over 20 years . My main electric bilge pump is located amidships and the outlet hose runs to the stern next to the engine outlet , with a built in float.originally a manual bilge pump mounted to the engine compartment with a hose disappearing into the bottom of the keel was used for this purpose . However I upgraded the system 20 years ago with a manual whaler hand pump . And then mounted it in the starboard lazarette. With an electric float actuated bilge pump as mentioned amidships . Mounted on a 1 inch teak platform glassed to the boat , she is still afloat tight and snug as a bug in a rug .living on the Columbia I also get a bit of rain . I humbly suggest you check and recaulk all standing rigging fittings and any other possible ares wear rainwater can invade your vessel . I invested in a canvas boom tent many years ago and it serves me well minimize the leaks and you will be well on your way to solving your problem .best of luck ,

[JBsurfin]

Originally Posted by nylajo

Due to the depth of the bilge that rums down the back of the keel, anyone have any suggestions how to stop bilge pump cycling, I have tried NR Valve but the bilge water always seems to leak back int to the bilge causing the bilge pump to cycle.

Confused over all these suggestions. I have a Dickerson ketch with a very deep bilge. Similar to you, and since my bilge is never dry and the pump has a long way to go to exit water. A simple check valve solved the problem of the back flow. and I was able to keep my high output pump in place.
Good luck and happy sailing.

[gulfislandfred]

Raise the float switch, so it doesn't turn on the pump until there's more water in the bilge.

Or raise the big pump, and install a smaller pump, as suggested earlier, to deal with rain water.


You might want to think about where the rain water comes in. I live on Gabriola Island, same climate. I've been able to keep the rain water out pretty well. A tarp over the hatch and forward part of the cockpit has done wonders on some boats, even if I couldn't see where the water came in.

[sinnerman]

As understood, the problem is that the bilge pump drain hose has a long run, and when the pump stops, all of the water that is still sitting in the hose drains backwards through the pump into the bilge. The bilge pump cycles since the returning water trips the pump water level switch and activates the pump.

I believe (?) this is a common problem with all bilge pumps. The check valve to keep the water from regurigtating back through the pump is a simple rubber duckbill (joker?) valve on the pump's outlet which does not seal 100%.

To keep the pump from "cycling" the (only) solution I see is to have the bilge pump switch actuate above the level of the water that "regurgitates" back to the bilge when the pump stops. The pump will now only kick in when the water rises above this new higher level. Of course you will now always have some standing water swirling around in the bilge...

Another option may be to install an impeller or diaphragm "self priming" bilge pump. These may be more resistant to backflow. Also since they can self prime, you can install them outside of the bilge, in-line / level with the drain hose, so there is less hydrostatic head on the pump forcing the water backwards.

Note that these pumps do not have the same "high capacity" as the "traditional bilge pumps (that is if you really believe that these little cheap plastic pumps can actually flow 1000+ GPH....). So, you may require two pumps: one to keep the bilge dry, and another to pull out water in a hurry.

I have a similar problem on my boat. I would like to have a dry bilge to keep the humidity and mold down in the boat. The little duckbill valve in my bilge pump actually actually does retain the water in the hose most of the time until... the wind shifts and blows over the transom where the bilge hose outlet is lcoated. The wind then pushes the water in the hose back through the pump into the bilge.

My (eventual ) solution is to install a "Dry Bilge" system to soak up the backflowed water. It will probably require pumping this water to a shower sump (i.e. a holding tank with "another" pump) then overboard.

My two + cents

Cheers.

[Nicholson58]

Originally Posted by nylajo

Due to the depth of the bilge that rums down the back of the keel, anyone have any suggestions how to stop bilge pump cycling, I have tried NR Valve but the bilge water always seems to leak back int to the bilge causing the bilge pump to cycle.

Same issue on Roxy. I added a 1-1/2 inch check valve as close to the pump discharge as possible about 8 years ago. No more problems.

This one. Buy a spare.