CalypsoL
27.05.2021 19:54:30
It is a rotating component of the pump. The runner gets power by an electric motor through a power shaft. It has one or more blades. here
See full version: What is a Bilge Pump? | How does a Bilge Pump work
It is a rotating component of the pump. The runner gets power by an electric motor through a power shaft. It has one or more blades. here
A bilge pump has two types that centrifugal and reciprocating bilge pumps. Here we will discuss the working of the centrifugal bilge pump.
It uses a single diaphragm or membrane for pulling and pushing the water. more
1) Clean the bilge:
If the ship has a small hole and is filled with water, the bilge pump can discharge water faster than the incoming water into the hole (depending on the size of the hole and the GPM of the pump). [links]
Most manufacturers rate their bilge pumps while running off 13.6 volts of DC power. But bilge pumps will only rarely see 13.6 volts in the wild. Batteries will only deliver that kind of power while being charged through shore power or with the engine running; they'll deliver considerably less when they're not being actively charged. In addition, the voltage at the battery will not be what reaches the bilge pump six or a dozen feet away in the bilge. Bilge pump wires are sometimes undersized, and connections are often corroded (it is the bilge, after all). All of this can decrease the voltage actually reaching the pump by 20 percent or more, and can easily result in a 20-percent drop in capacity. To maximize voltage to the pump, clean all connections regularly, and check the wire-gage recommendations for your pump size. If that wire's undersized, up-size. And if you decide to install a higher-capacity pump after reading this article, make sure to put in a new, larger wire. more
Most manufacturers also rate their bilge pumps when pumping water horizontally. But bilge pumps are located in the bilge — below the waterline. Water is going to have to be pumped UP to reach the outlet, and it will have to go even higher if the outlet hose includes an anti-siphon loop above the waterline, as it should on most boats. Therefore, in the wild, all bilge pumps have to lift the water some amount of vertical distance — called head — from the bilge to the top of the anti-siphon loop or to the outlet. Head is expensive in terms of pumping capacity. Three feet of head height, as might be found on larger powerboats, decreases the capacity of that 500-gph pump by about 30 percent. Six feet, as could be necessary on a large sailboat, decreases capacity by more than 40 percent. Assuming the anti-siphon loop is appropriate for your boat, there's no way around that loss of capacity. If you want to move a lot more gallons per minute than you are right now, you'll have to up-size the pump. more
Having gone through this exercise, you may be wondering how much your pump will really move in a minute or an hour. One easy way to find out is to pour five gallons of water into the bilge and start your stopwatch when the bilge pump kicks in. A 500-gph pump should empty the bilge in 35 seconds if it's working at its rated capacity. A 1,500-gph pump should be able to do it in 12 seconds. Of course, given all of the above, it's more likely that 500-gph pump will take longer than a minute to get rid of the water. Eighty to 90 seconds wouldn't be unheard of, and the 1,500-gph pump will take 25 seconds or more. Do the math to see how your bilge pump stacks up against the writing on its side.
If you have any boat larger than a small runabout, chances are you have an electric bilge pump somewhere aboard. That bilge pump is not intended to keep your boat afloat in the event of a hull breach, but simply to remove "nuisance" water — including, among other things, small amounts of spray or rainwater that come in when the companionway is open, drips from the stuffing box, or leakage or seepage from a deck fitting or port light that's not quite watertight. Though those bilge pumps are not intended for hard duty, the BoatUS Marine Insurance claim files show that in many cases, sinkings have been delayed and even avoided because a bilge pump kept up with a small leak and allowed time to fix it before it became a large leak. Conversely, many sinkings involve a bilge pump that has been ignored for weeks or months as it cycled increasingly frequently, or one that has run the battery flat in a relatively short period of time when the volume of water entering the boat led to continuous running of the pump.
All bilge pumps on the boat should be accessible, so you can inspect the pump and its float, and clear debris from around the pump pickup. If the pump is located in a spot that’s inaccessible or hard to reach, such as below the engine on a sterndrive boat, consider relocating it if possible. more
The pump may have a float or switch to turn it on automatically when water collects in the bilge. This is especially important if the boat is kept in the water, as you’ll want the pump to activate after a heavy rain storm, for example. The pump may also just have a manual switch at the helm. Often the bilge pump switch has an “auto” and “manual” setting. more
If the discharge hose is a corrugated type, replacing it with a smooth-wall hose can increase the flow rate by up to 30 percent. It seems logical that a small boat can make due with a pump with a lower flow rating, but the opposite is true; in an instance of a hole in the hull or another major incident, that water is going to impact a small boat much faster than it will a larger boat.
The function of the bilge pump is to remove water that collects in the bilge, which is the bottom of the inside of the hull. Most of the time, water that collects in the bilge is incidental:
Why doesn�t the Bilge Pump shut off�?
The float switch may be stuck in the up position: Check for debris, dirt, fuel or oil residue from bilge water. The float switch is in the down position: The mercury capsule may be stuck in the on position. Tapping on the float may free it, or if needed replace float switch. Wire connections may be incorrect. Automatic pumps may have faulty circuit. Possible electrical short
Bilge Pump has flow or reduced flow?
Pump must be wired with correct polarity otherwise the pump will operate in reverse rotation which will reduce flow to less than half volume. Brown Wire - positive, automatic feature for Computerized Automatic and Rule-Mate Pumps. Brown/White Wire - positive, manual override feature. Red Wire - positive, manual feature for Computerized Automatic and Rule-Mate Pumps. Black Wire - negative
Bilge Pump runs but no water is pumped?
When the bilge pump is operating but no water is being discharged this is typically caused by an air lock. An air lock occurs when air is trapped in the impeller chamber; centrifugal pumps by nature will only move water (not air) and do not have the ability to self-prime. Do not install a check valve on the pump discharge. Air can trap in the discharge hose if a check valve is installed. A dip or drop in the discharge hose can create an air lock which will prevent the pump moving water. Inspect and reposition discharge hose for a short vertical discharge. Install pump below water line to insure sufficient water flow. Pump strainer and impeller area can be clogged with debris. Disconnect pump from strainer and wiring and clean debris around strainer and impeller, reattach strainer and re-hook wiring. [links]
Bilge Pump impeller spins backwards?
Pump must be wired with correct polarity otherwise the pump impeller will spin backwards which will reduce flow to less than half volume. Brown Wire - positive- Automatic feature for Computerized Automatic and Rule-Mate Pumps.; Brown/White Wire - positive- Manual override feature; Red Wire - positive- Manual feature for Computerized Automatic and Rule-Mate Pumps; Black Wire - negative
Bilge Pump just installed and is not working?
Confirm fuse was installed into fuse holder. Check to see if the fuse is blown. Confirm the voltage at the pump through the wiring connections with a Volt Meter to confirm the pump is getting enough power. Confirm the installation uses the correct size wiring. [links]