See full version: What Does a Bilge Pump Do
Manual pumps however have the advantage of their ability to be used, even when you are out of battery power. For small boat owners who are not willing to spend extra money on efficient electric pumps, a manual pump can come in handy. They are limited in their pumping capacity, and to the endurance of the person exerting the pumping effort. here
The bilge pump serves to evacuate accumulated water and oil from your boat. During normal operation, it provides a convenient way to keep your boat dray. It can buy time in potentially hazardous situations like a major storm or a leak from hull damage. , keeping you and your passengers safe until repairs can be made.
There are catalogues and tables of estimated pump capacity for different boat sizes, put together by experienced boat professionals. These serve as good reference points when matching pumps to a boat size. more
Also, due to their large weights, collisions are likely to create more pronounced damage. It’s not possible to place an exact value on the required pump size for a particular boat, but good approximations can be made while staying within ranges of safety. more
Many boat owners keep an extra bilge pump on hand, or replace their bilge pumps with larger ones. It should be noted however, that for long – distance travel, human lives are at stake and in the situation of danger, help would take time to arrive. The bigger the bilge pump you buy, the higher your chances of survival if hull damage indeed occurs.
Keep in mind that your approach to the discharge fitting of your boat will depend greatly on the boat’s materials. In many cases, you will be replacing an existing bilge pump, so your boat will already have a discharge system in place. If this is the case, you can simply fit your new pump to the existing discharge hole.
However, don’t let your commitment to a straight hose force
you to run it through vital components on your boat, either. Do your best for
optimal efficiency and safety.
Typically, this will mean trying a configuration with the hose before you
install it on the pump. [links]
The configuration of your hoses may seem trivial, but it can
have a big impact on the overall efficiency of your bilge pumping system.
You’ll want smooth hoses with as little bending and running as possible. The
straighter you can get the hoses to work and dispense the water outside, the
better. Try to avoid using corrugated hoses here, as these can sometimes get in
the way of proper water flow even if you do have a straight hose system. here
With your water line marked during your preparation phase,
you’ll have no trouble ensuring that the bilge pump discharge comes from above
the water line. You don’t want your system to bring in water during surges and
waves, so it’s important to give your discharge enough space that it remains
consistently above water. Don’t let the fitting of the discharge go below the
water line.
Before we get started, here are a few things you’ll need to
know: more
An effective bilge pump is essential if you’re going to keep
your boat in pristine condition. If you have a faulty bilge pump that’s not
pumping out old water effectively, it may be time for total replacement. To
help, we’ve put together this brief guide on installing a bilge pump on your
boat!
Re: locating the bilge pump
Yup, very common for a pump to suck up bilge trash, could be a candy wrapper ect ect but it does sound like it still at least trying to work. more
Disconnect pump. If you don't have the problem then it is the wiring of the pump to the lights. It should be seperate and maybe have a fuse. [links]
Reading my colleague Lenny Rudow's piece yesterday entitled "Installing New Bilge Pumps, Read This First" made me think of an on-going issue with bilge pumps and any small motor circuit you install on your boat, macerators, bilge blower fans and such. The issue is called "locked rotor" and what happens when this occurs. A locked rotor situation is basically defined as a motor that's trying to turn, but can't, for whatever reason. In the case of a bilge pump motor any bit of debris that enters the motor housing around the pump's impeller and wedges itself between the motor housing and the impeller could jam the pump so that the impeller can't turn. The problem is, your float switch doesn't know that. When the float reaches its turn on point, its still going to send power to the bilge pump motor. what happens next is the tricky part. The motor has power so its trying to turn but can't. So what happens electrically here is the interesting part. You have a voltage source, and a device trying its best to function. It does the only thing it can do at this point, generate heat. In fact maybe even enough heat to catch on fire. The electrical current is flowing, but gets reduced based on one of the key electrical equations we have, Ohn's Law. Ohm's law states that if voltage is a constant and electrical resistance increases, amperage must go down or be reduced. That's whats happening here, the voltage supply is pretty steady from your battery, the motor is heating up and that increases electrical resistance, amperage goes down. Its a mathematical fact. The problem is, we would hope a fuse would blow in this case and shut down the power to the motor. It won't. Why? Because fuses blow based on amperage and if the fuse is not being subjected to enough amperage, its just going to sit there and allow whatever current there is to flow freely. The simple answer to this problem is to be absolutely certain the fuse for your bilge pump motor is rated exactly as the motor manufacturer recommends and that's where the installations typically go wrong. The vast majority of blower fan and bilge pump circuits are over-fused, and in the event of a locked rotor will not blow! In the photo below, you see the beginning stages of what can happen. Mind you I disconnected the power to this motor after about 20 minutes. If you turn sideways and look very carefully at the printed information on the top of the pump you'll see that Rule recommended using a maximum 11/2 amp fuse (this one is a 24 volt motor). All I did to get the melt down going was lock the motor impeller in a vise and install a 5 amp fuse. Again, within about 20 minutes the case got hot enough to start melting as you can see. Had I left the power connected, it would have eventually caught on fire. So, besides Lenny's sage advice about adding a vented loop to your near the waterline bilge pump installations, make sure the fuse you use matches what the pump manufacturer recommends, and no more.
If you turn sideways and look very carefully at the printed information on the top of the pump you'll see that Rule recommended using a maximum 11/2 amp fuse (this one is a 24 volt motor). All I did to get the melt down going was lock the motor impeller in a vise and install a 5 amp fuse. Again, within about 20 minutes the case got hot enough to start melting as you can see. Had I left the power connected, it would have eventually caught on fire.
In the case of a bilge pump motor any bit of debris that enters the motor housing around the pump's impeller and wedges itself between the motor housing and the impeller could jam the pump so that the impeller can't turn. The problem is, your float switch doesn't know that. When the float reaches its turn on point, its still going to send power to the bilge pump motor. what happens next is the tricky part. The motor has power so its trying to turn but can't. So what happens electrically here is the interesting part. You have a voltage source, and a device trying its best to function. It does the only thing it can do at this point, generate heat. In fact maybe even enough heat to catch on fire. The electrical current is flowing, but gets reduced based on one of the key electrical equations we have, Ohn's Law. Ohm's law states that if voltage is a constant and electrical resistance increases, amperage must go down or be reduced. That's whats happening here, the voltage supply is pretty steady from your battery, the motor is heating up and that increases electrical resistance, amperage goes down. Its a mathematical fact.