Electric bilge pumps on sea kayak-questi

Since the conditions that capsized you and really put you into trouble are likely to be the ones where you can’t afford to use a hand pump, I decided an electric bilge pump is essential for sea kayaking.

Considering the three to five foot dumping and white capping waves on Lake Erie, I’m a little hesitant to try the traditionally recommended magnetic reed switch. Can’t the magnet be easily thrown off of the switch from the waves going over the deck? Also, can the water go up the gland and through the bilge pump flooding your cockpit when you are just practicing rolling?

Use a foot pump mounted…
on your front bulkhead.

bilge pumps
are designed to pump out not flow in…but there are check valves available…see West Marine.

try an enlgish langage search


Maybe some sort of detent
I tried a foot activated switch, but I am far happier with the reed switch.

I have never used my system in heavy surf such as you describe. However, if concerned about it, I think I might try forming some sort of indentation or cradle that will tend to make the magnet stay put. For example, you could run a bead of adhesive around the spot where the reed switch is. You’d have to lift the magnet slightly to move it to/from the on position, but it would tend to stay there until you lifted and slid it off.

I don’t have a check valve in my system. I don’t think it takes in much water when rolling. I suppose if you had waves constantly dumping on the deck where your pump port exits the hull, you could get some water.

Search out gnarly dog. He seems to be the expert in electric bilges, and I would rely on what he says.


But have you tried?
I’m not trying to be snarky, but have you done much paddling in rough conditions to really determine how much water you will get in the boat? I have paddled a lot in rough water and getting water in the boat has never been a problem with a proper spray skirt.

Now if your plan is to purposely get out there and see how often you can get dumped, that’s a whole nuther matter.

NO to both of your questions
The reed switch will not move. You can use a piece of 3m not slip tape on the deck, and then run your deck bungee through your swtich. Make the bungee really tight and the switch will not move around.

You can install a loop of hose, a one-way valve, or just do nothing, either way no water will come in. In order for water to come backwards through the pump it would have to spin the impeller backwards, and for that you would need pressure.

You can view the build that I did here:


I built one and it worked great
Never had it turn on by accident. The switch is just a magnet glued inside a block of plastic that slides on the bungee. Battery box in the day hatch, pump behind the seat. Battery is a LiPo RC car battery from a hobby shop along with a relay in a small pelican case velcroed to the day hatch bulkhead. I used sealing connectors from McMaster-Carr and liquid-tight feedthroughs on the bulkhead connection.

The reed switch is under the deck, glued and covered in 1/4" foam so you can’t catch with your knee. Lots of coastal rough water and never a problem. I have a good roll but have used it a couple of times when I got pummelled too badly by surf and ran out of air and once getting sucked into a big whirlpool in a tide race. I turn mine on then reenter and roll.

Even with a proper fitting spray skirt everyone gets water in their boat if it’s rough. Mine gets most of the use emptying the bit of water out of my boat before I drag it up the beach.

my setup

– Last Updated: Oct-02-15 11:23 AM EST –

edit: My setup ONLY weighs 3 lbs total including battery. Battery choice is key.

Here is my setup with reed switch on my now sold NDK Greenlander Pro. http://www.pbase.com/dc9mm/kayak_bilge_pump youtube video link on that web page.

I have same setup in my Valley avocet RM which I go out in Lake Erie in 6 foot waves for surfing. also have pump on my QCC 700x here is video of it pumping out. http://www.youtube.com/watch?v=yrZwVowYlyg
QCC exit is in back were my other 2 kayaks exit in front.

Reed switch wont go on by itself BUT you can hit it with your hand if your not watching. No big deal just slide it to off if that happens. You will hear the pump even in big waves. I use lithium Polymer battery which last a long time at 2.5 amps and only weight 9 ounces.

And no water wont flood kayak if you roll. I have rolled OVER 30 times in less than 20 minutes and what water comes in is by the skirt. Even then its not enough to even turn the pump on as the pump WONT get ALL the water out. Its gets most but there's still enough left to sponge out.

Water Witch
I bought a thing called a Water Witch (101 series). It cost me about $40 for the switch and it works like a charm, there are no moving parts and you can set it to the height you want by zip tieing it to the pump. West Marine also sells a check valve for around $15. The parts are replaceable and you’ll want that to keep water from flowing back into your boat. I’ve included the links below.

I agree with you about hand pumping your boat in rough water. Why do it when you can instal a bilige pump? I personnaly think they should be on every touring kayak sold but that is another topic. I can do a self rescue get back in my boat and be on my way while the boat is pumping out the water. I had a leaky spray skirt on a trip this summer and was in pretty rough water (5’ plus waves). Every half an hour or so the pump would empty out the little bit of water that had collected in my boat, it was awesome.



I may be a moron
but what activates the reed switch when you need the pump?

The magnet they are discussing.
The reed is glued to the underside of the deck below the bungee. When you slide the magnet above it, the reed closes.



Thank you.

electric bilge pump details
a few articles on electric bilge pumps in my kayaks here:

  1. switch : http://gnarlydognews.blogspot.com.au/2009/11/electric-bilge-pump-switch.html

  2. the whole contraption : http://gnarlydognews.blogspot.com.au/2009/04/shop-electric-bilge-pump-in-kayak.html

  3. behind the seat, with seat close to bulkhead: http://gnarlydognews.blogspot.com.au/2009/10/shop-recess-in-bulkhead.html

bilge pump
I agree with Magooch. A good skirt will keep water out of your cockpit until you capsize. A roll will keep you upright. An electric pump requires a battery. Boats sit a lot. The bilge pump will probably work fine right up until it doesn’t. I would focus more on rough water paddling technique, and judgment about when to paddle.

Also, leave at home VHF and GPS
If battery use is grounds for disqualifying equipment, I guess we should leave the GPS and the VHF radio at home, too. Oh, and cameras? Just bring the old Kodak with the thumb winder to advance the film. Oh, and nav lights for when it get’s dark–just bring a candle lantern.

I like my electric bilge pump. I still carry a hand pump, because it’s good to have backup, but I haven’t had to use it since I went electric.