PaddleWise Discussion on Electric Bilge Pumps

A big thanks goes to Bob Volin for organizing this PaddleWise Discussion on
Electric Bilge Pumps for this website.

Date: Tue, 12 Jan 1999 06:52:32 EST
Subject: [Paddlewise] Electric bilge pumps

We've kicked this issue around on Paddlewise in the past, and I think I
remember that it was our folks in OZ and Kiwi-land who'd done the most work on
mounting small electric pumps in kayaks.  Maybe not.  Just looking for some

I'm in the last steps prior to installing the deck panels on a Chesapeake
Light Craft (CLC) North Bay, and wanted to stop to consider mounting a Rule or
other small pump and battery pack in the boat while it's still workable.  Any
suggestions, pro or con, and, if pro, which pump and ways in which it can be
most effectively installed?  How big a battery pack?  What kind?  How to
install a switch and where ... foot operated or thru-deck?  A caution: any
post-installation maintenance is going to require going into the aft
compartment through a 4.5" diameter access plate in the rear bulkhead, and
replacement battery packs are going to have to live with that restriction, as
well.  This is a new, low volume "Greenland" style boat at CLC, and the
maneuvering room inside the hull, once the deck goes on and the ring nails go
in and the epoxy cooks off, is extremely limited.

With those caveats, any ideas?

Jack Martin

Date: Tue, 12 Jan 1999 16:09:35 -0600 From: "Dickson, Dana A." Subject: RE: [Paddlewise] Electric Bilge Pumps I have a Rule 1100 mounted in my CD Storm. I put it behind the seat. I use a 7 amp-hour gel cell battery. Based on the amp-hour capacity of the battery, the current draw of the pump and a fudge factor just because I expect the battery could last for about 3 hours of use before it needed to be recharged. I have used it extensively when I was practicing self rescue and learning to roll, these were far more intensive use than I would expect to need in real situations and I never depleted the battery. My battery is about the size of two video cassettes, smaller and lower capacity batteries are available. I have had lots of problems with the switch getting water in it and failing. My latest attempt is to coat the switch body with two layers of silicone and to seal around the switch lever with silicone grease and a boot from the switch manufacturer. The last attempt was just sealing at the cracks on the switch and using the boot, that failed after a couple of months of intermittent use. The mounting location for the switch is an issue. While I am experimenting I Have kept the switch mounted under the spray skirt on the side of the seat, a protected out of the way location. When I am satisfied this will all work consistently I will take the suggestion of the one of south pacific subscribers and mount the switch on my foredeck with a protective shroud. The other problem with the electric pump is that the Rule 1100 loses suction with about 3/4 inch of water in the bilge. That is enough water to make the boat noticably less stable. OTOH, it talks less of my energy to pump the boat with the switch and supplement with the hand pump than to hand pump the whole cockpit dry. This may be amenable to a fix with creative fiberglassing or the use of a pump that will take a pickup hose like I have seen with foot operated pumps. Dana Dickson
Date: Tue, 12 Jan 1999 17:47:31 -0500 From: Bob Denton Subject: RE: [Paddlewise] Electric Bilge Pumps I believe Valley sells a box type fitting for the hose that will remove most of the water from the bilge. The actual name escapes me at the moment. cya
Date: Tue, 12 Jan 1999 18:36:36 -0500 From: Andy Knapp Subject: [Paddlewise] Electric Bilge Pumps "I believe Valley sells a box type fitting for the hose that will remove most of the water from the bilge. The actual name escapes me at the moment." It is called a strum box, and is available from dealers of Great River Outfitters, importers of VCP products. (248) 683-4770, - -Andy Knapp
Date: Tue, 12 Jan 1999 18:14:10 -0500 From: Bob Denton Subject: [Paddlewise] Bilge Pump Strum Box A Strum box is available from Great River Outfitters for $19.95 which "allows removal of the last drop of water from the cockpit" 248-683-4770 cya Bob Denton Aqua-Gulf Transport
Date: Tue, 12 Jan 1999 16:09:15 -0800 (PST) From: Julio MacWilliams Subject: Re: [Paddlewise] Electric bilge pumps I have a Rule 500 operated by a waterproof switch, both of which I obtained at West Marine. For the battery I use two lantern batteries connected in series inside a plastic bag. I have not had a chance to count how many times the cockpit can be emptied before the battery dies. Does anyone have experience using gel batteries? Can they be submerged? Or do they have to be sealed from the outside like I am doing with the lantern batteries? - - Julio
Date: Tue, 12 Jan 1999 22:06:21 -0500 From: "Robert Woodard" Subject: RE: [Paddlewise] Electric bilge pumps Does anyone have experience using gel batteries? Can they be submerged? Or do they have to be sealed from the outside like I am doing with the lantern batteries? I have a Attwood 450 ($9.95 at Wal-mart, but I had to order the hull connector through the internet) and a YT4L-BS (about $35, also from WalMart). The battery is about the size of a single lantern battery. I also outfitted the the kayak with an external power connector (looks like a car cigarette lighter receptacle with a weather flap - about $4 at Wal-mart) so I can plug in other devices like my GPS. So far I've only dunked it in fresh water. No problems with this, but I am concerned what might happen in salt water. Woody
Date: Wed, 13 Jan 1999 15:21:24 +1100 From: Peter Rattenbury Subject: [Paddlewise] Electric pumps and a Klepper Remarkably, 12,000 miles away in the South Pacific, I decided on similar technology to Dana in sorting out an electric pump. I run to a 1000gph Rule pump, and like Dana, a 7 amp/hour sealed lead acid rechargeable battery. I am still in the 'sea trials' stage with the thing installed in my Klepper Aerius 1. With a high volume boat like the Klepper I took the view that massive over capacity in the pump department was the way to go. I too have used switchgear with a manufacturer's 'waterproof' hood over the toggle and can report no problems so far with corrosion, shorting etc. after several months of use. All electricals are sealed in marine Sealastic. The carpentry involved in the fitting will probably only interest Klepper owners, but basically the battery, pump, fuse and switchgear have been fitted as a portable unit and are all velcro strapped and screwed on and through a base plate fitted to the boat just forward of the seat. The pump's exhaust hose is stored around the unit and deployed [ if I am not sailing] through the mast step in the coaming. I am usually in open ocean conditions so I normally use Klepper's cockpit cover. The whole pump bag'o'tricks is easily removed from the boat. It all sounds rather sloppy but like everything else, familiarity with the gear under all sorts of conditions is the key. And of course, 'failsafe' back up systems are vital; in this case, a hand pump [ the red-handled kind familiar to most Americans] and a good old collapsible bucket. Maybe other Klepper owners have comments? Regards, peter rattenbury
Date: Wed, 13 Jan 1999 09:01:15 -0600 From: "Dickson, Dana A." Subject: RE: [Paddlewise] Electric Bilge Pumps I have seen the fitting you describe on pumps in boats with permanent pumps. A pump with a hose inlet rather than the open inlet on the standard bilge pump would have to be used. Rule makes a live well pump that might work, although I suspect that the live well pump like the bilge pump will need to be submerged to be primed. Dana Dickson MIS CIH CSP Principal Industrial Hygienist Unisys Corporation
From: Bob Volin Date: Wednesday, October 13, 1999 12:09 AM Subject: Re: [Paddlewise] Rule 800 rules! (was waterbuster I've just installed two Rule 500 pump systems in my wife's and my boats (both Romanys, or British Heavies). Forgive me if this is a bit long. Components: Pumps: Rule 500 Hose: standard 3/4 inch plastic "bilgeflex" hose Batteries: small 12-volt maintenance-free motorcycle batteries, model BT4L-BS. According to the charts, these batteries are meant to power Honda 50cc bikes. The battery salesman advised me to charge the batteries monthly, whether I use them to pump out the boat or not (e.g., winter). Battery Charger: 1.25 Amp automatic type (shuts down automatically). Waterproof battery containers: 1.7 quart Rubbermaid containers. Switch: Small push-on push-off switch, single-pole, single-throw. Switch container: Small Radio Shack plastic "project box." Switch protector: 8-mil clear plastic sheet (the type used to protect cash register keyboards at auto repair shops). 24" x 12" is more than enough for 2 switches. Check valves: These permit water flow from the pump and prevent backflow. I used a modified 1/2 inch pvc valve designed for home plumbing systems. I decreased the opening pressure (200 psi) by unscrewing the spring cap, cutting the spring roughly in half, bending the cut tip to fit the cap, then putting it all back together. This cut the opening pressure acceptably, so that the valve did not appreciably slow the pump's outflow. Through-hull fitting: 3/4 inch. Wiring: #16 automotive or marine wire. Waterproof inline fuse holder Plugs: automotive trailer plugs (2-wire) Assorted bits & blocks of minicell foam Waterproof glue, silicone sealer, Epoxy Here's how it was assembled: The battery case is firmly mounted inside a carved out space in a minicell form, cut out to fit the boat, just ahead of the forward bulkhead. I left spaces on either side of the minicell form to pass the wires that come from the cockpit and through the bulkhead. Where wires pass through the bulkhead, the holes are sealed with several coats of silicone on both sides of the bulkhead. Small holes were drilled in the battery case lid for the wire leads, and sealed with several layers of silicone inside and out. Following the wiring diagram that came with the pump, a waterproof fuse connector was placed on the positive battery lead. The battery leads were terminated in a waterproof automotive plug (the sort used for trailer lights). The other end of the automotive plug is connected to the wires that pass back through the bulkhead into the cockpit. I left enough wire to be able to brihg both sides of the plug into the forward hatch opening, for easy handling. When we're off the water, I unplug the systems and don't have to worry about accidental running of the pump while the boats are being handled or are in transit. Unplugging this way also allows me to remove the batteries, still in their cases, between uses. On the cockpit side of the bulkhead, the wire that comes from the fused positive side of the battery is connected to the pump (brown lead), and the other wire is connected to one side of the switch. The switch was (perhaps still is) the biggest challenge. I was unable to find a submersible switch other than the very large and bulky ones sold for powerboat bilge systems. Actually, I did find another source for submersible switches, but they supply switches for underwater oil rigs and submarines. Although a price was never quoted, I was given to understand that these switches were not in my range. But I digress. Drilling holes of the appropriate diameter for the switch and wires, I mounted a small push-on, push-off switch in one end of a plastic Radio Shack project box, and ran the wires out the other end. I used gobs of silicone to seal both holes and the edges of the box. This did not make the switch waterproof, so I cut squares of 8-mil plastic (the kind that might be used to protect cash register keyboards in auto repair shops), wrapped them around the end of the switch and the box with gobs of silicone underneath, then tightly taped the mess to the box. When the silicone cured under the tape, the switch was sealed (I hope). One lead from the switch passes through the bulkhead to erminate in the auto plug (mentioned earlier), and the other is soldered to the black lead of the pump. I mounted the switch box just to the left of the head of the keyhole cockpit, such that the switch is just below and flush with the coaming. I find that I can feel for and push the switch through the neoprene spray skirt. A word about splices and holes drilled in bulkheads. All wire joins were Western-Union spliced and soldered. The soldered joints were then sealed with silicone and covered with electrical tape. More silicone covered the tape, in the hope that this would delay any displacement of the tape. (The adept amateur electrician can also consider using waterproof shrink wrap). I don't recall the diameter of the drill bit I used to bring the wire through the bulkhead and battery case lids. However, I used #16 wire (as recommended by Rule), and the drill bit was the narrowest that would allow passage of the wire. As a general rule, wires running inside the cockpit were secured with plastic wire wraps. These can be wrapped around the foot peg tracks (if you don't care about adjusting your pegs very far), or can be secured with wire wrap anchors that can be epoxied to the cockpit alls out of the way. Another way to keep wires out of the way would be to cover them with wide Velcro strips. Now the pumps. I mounted mine at the midline of the forward bulkhead. The mounting bracket is epoxied to a small rectangle of minicell, which in turn is epoxied to the bulkhead. I tried to bond the plastic bracket directly to the fiberglass bulkhead, but the bond didn't hold over a weekend of paddling. The pump is positioned so that the output points to the right. The output hose curves right, then up, then back to the left above the pump. This minimizes the possibility that air bubbles will form in the hose. The hose connects to a check valve, which is in turn connected to the through-hull fitting. The hole for the through-hull fitting (3/4 inch) was drilled on the left at the uppermost flat portion of the hull, just off the forward bulkhead. Since the front of the cockpit is higher than the seat area, this arrangement left about 3/4 to 1 inch of water in my boat after a full drain. My wife, Joan, wanted better. So we tried mounting her pump just behind and to one side of her seat. The theory here was that with the pump in this position she could edge the boat to the pump side to get those last few dregs. The rear bulkhead in a Romany is slanted, so a wedge-shaped minicell block was used to epoxy the pump bracket to the bulkhead. With pump mounted on the right side of the boat, the outlet was aimed to the left. The hose is directed up (to minimize air bubbles) above the bungies that hold the back support in place. Again, the hose connects to a check valve and the valve connects to the through-hull fitting, which is mounted as high as possible just ahead of the bulkhead. About the check valves: I received the West Marine catalog only today, and found several varieties of check valves there. I'd suggest looking into these before you perform surgery on the household type I used. In our boats, given the way the pumps were positioned, each system required only a single one-foot section of hose. That will, of course, vary with different boats and different pump placements. Does it work? In various tests, yes. The pump will empty a full cockpit in around four minutes. I've read on this list that the battery should run the pump continuously for 3 hours. Lessee, that works out to about 45 bailouts of a full cockpit before having to recharge..... And does it work in "combat?" Yes. The other day, Joan missed a brace in confused seas and came out of her boat. We did a standard "T" rescue, in which I emptied her boat the usual way before she got back in. Naturally, a substantial amount of water entered the cockpit as Joan re-entered. While she was settling back in, we ran the pump. The boat was essentially dry and fully stable by the time she was ready to get under way. She never had to contemplate the tiring business of pumping by hand. I guess that's it. Oh. Why the Rule 500 instead of the 800? As someone recently pointed out, postings on this list some time ago indicated that the 500 was the star of several reliability tests. Given that information, it seemed to me that a full emptying of the cockpit in 4 minutes, while I would have both hands on my paddle, is likely to be fast enough. Please feel free to offer comments, modifications, razzberries, whatever. Bob Volin