Thread: How do I choose a bilge pump, if at all?

There's only one rule to sizing a bilge pump, install the biggest darned one you can. A quick moving thunderstorm can dump enough rain to easily overwhelm a small pump. A small leak or hole can permit a huge amount of water to enter a boat, especially powerboats when underway. I usually install two pumps, one slightly higher then the other, which works as a back up. The idea is if the first pump isn't keeping up with the leak, then the water level rises to the second pump and it kicks in to help out.

Floatation in your boat that's enough to save the boat, means it's just barely afloat and this requires a lot of the internal volume of the boat be used up with this floatation. It's a stop gap measure at best, so rely on pumps and scuppers, not foam.

Hi Andrew.

PAR is spot on with his advice.

RULE, make a big range of pumps, readily available in Aus and good quality, including any type of switch system you choose.
Get 2 of the best you can afford.

The best bilge pump. "a scared man in a sinking boat with a bucket." Sorry. Could not resist that old joke.

Paul.

Does it have to be one or the other?
Flotation & bilge pumps do two different, although related, jobs.

The bilge pump/s manage (relatively) small events & keep you functional to
return to the ramp or to the nearest patch of dry land. For as long as there is
power to drive them anyway. The bigger the pump, the more power they consume,
so you need to match that against alternator output & battery capacity.

Flotation (foam/bags/compartments) keeps you from losing the lot in the
event of catastrophic failure/collision.
Also makes it possible to stay in/with the boat.
Port Phillip bay is a big place. I'd hate to be just a head in a PFD type 2 after dark.
And I saw the aerial pics of the sharks near the Rip published in The Age back
in the '80s...

So I'd go for both if I could afford it.
If I couldn't afford both... I'd be the dissenter to the above advice.
My life is worth more than my convenience. I'd add flotation first.
The US Coast Guard has a good guide on calculating how much you need & where
to put it. http://www.uscgboating.org/assets/pd.../FLOTATION.pdf

Then I'd put in the biggest, gruntiest pumps I could afford (and power) second.
I like the configuration PAR recommends. Makes seriously good sense.

cheers
AJ

I go along with PAR regarding the bilge pump setup, that is, go big rather than small in the hope you will never need it. Brave lad going out in Port Phillip Bay in a PFD 2 rather than a PFD 1. Yes I know they both keep you afloat, but it's how they keep you afloat. The phone is a nice idea and seriously worth having but don't rely on it as your only means of communication because it's very hard to describe to someone who maybe looking for you where exactly they should be looking for you when the horizon is only three feet in front of you. I used to work as a SAR diver and you have no idea how hard it is to see someone in the water even when they are trying to attract your attention. Port Phillip Bay during the day, smoke flares and a handheld water resistant VHF, night time VHF again and also maybe either mini flares or parachute flare. The mini flares can be sown onto your life jacket so you always have them on you and from memory there are I think ten to a pack so you have ten chances for someone to see it.

If installing an auotmatic bolge pump on a float switch it is really good idea to have the output tube exitting the boat in a position that is very noticable from the helm position.
Not only does this tell you that the pump has been running for along time but may may also alert you to other foriegn matter being pumped from your bilge. An alerting dash light to tell you the pump is running is also a good idea as this will tell you if the float switch has jamed and has continued to drive the pump witout water. A nhand operated bilge pump is also a worty consideration.

The simple addition of a light, when the pump is running is a common and desirable method to install a bilge pump. I install them the same way, regardless of boat or customer, they get a switch panel with a light mounted in a conspicous location, typically on the instrument panel. The DPTT switch offers an "Off" position, also an "On" position which turns on the pump, regardless of float position and an "Auto" position, which permits the pump to work if the float switch says it should. In the "On" and "Auto" positions, the light will come on if the pump is running. This is the only way I will install a pump and a good point that an Old Codger brings up.