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Long Beach Marine Electric connects boat owners with licensed, insured marine electricians for bilge pump repair: pumps that run on manual but not automatically, pumps that won't shut off, float switches that stick, blown fuses, and missing high-water alarms. The automatic bilge circuit is the one that protects a boat while nobody's aboard, and BoatUS research found boats sink at the dock four times as often as underway. If water is coming in now, call immediately.
What happens on the first visit
- Manual and automatic test with water, not just a switch flip: does the pump actually move water overboard, and does the float or sensor start and stop it?
- Check of the automatic circuit's power path. It should stay powered with the battery switch off, with its own fuse close to the battery.
- Voltage at the pump under load. Bilge pumps lose a large share of their flow when voltage sags.
- Inspection of the float switch, the connections down in the bilge (the wettest, most corroded spot on the boat) and the discharge hose and check valve.
- A written finding and a fixed price before any parts go in.
Why bilge pumps fail at the dock
A bilge pump rarely dies on its own. The circuit around it fails first. Float switches stick with debris or wear out. Connections at the bottom of the bilge sit in salt water and corrode. Automatic circuits get wired through the main battery switch, so they're dead the moment the owner switches off and walks away. And a dead battery bank means no pump at all.
The consequences show up in insurance data. BoatUS's Seaworthy research found recreational boats sink while tied to the dock more often than underway, by about 4 to 1, and nearly half of those dock sinkings followed heavy rain. Long Beach gets most of its rain in a few winter storms, which is exactly when an untested automatic pump gets its first real workout.
Works on manual, not on auto
This is the most common bilge call. Because the manual switch bypasses the float, a pump that runs on manual proves the pump and its main wiring work, and points at the float switch, its wiring, or the separate automatic circuit and its fuse. Internal sensor switches can't be lifted by hand to test, which makes them harder to diagnose. External float switches are easier to verify and replace.
ABYC guidance calls for the bilge circuit's fuse within 7 inches of the power source, and wire sized so the voltage drop stays within 3%, because pump output falls fast when voltage sags. Plumbing matters too: Practical Sailor notes a single 90-degree bend in 1-inch discharge hose acts like adding 3 feet of hose, enough to cut a 3,000 GPH pump to about 2,000 GPH.
High-water alarms and second pumps
A high-water alarm tells you, or a neighbor, that the primary pump is losing. ABYC standards call for an alarm on boats with enclosed accommodations, loud enough to hear over the engine. For boats left unattended for long stretches, a second automatic pump mounted higher in the bilge, on its own fused circuit, is cheap insurance. Both should be tested with water, regularly, not just with a switch.
Insurance, warranty and who pays
Bilge pump and float switch repair is owner-paid and usually quick: most float switch replacements and rewires take one to two hours at the slip. If the boat has already taken on water, contact your insurer as well. Sinking damage is typically a covered loss, but the failed part itself usually isn't.
What's included
- Water test of manual and automatic operation
- Float switch or sensor replacement
- Automatic circuit wired to bypass the battery switch
- Fuse sized and placed near the source
- Corroded bilge connections replaced and sealed
- Voltage check at the pump under load
- High-water alarm installation
- Second pump on a separate circuit
DIY vs cheap fix vs proper bilge work
| Factor | DIY | Cheap operator | Proper marine work |
|---|---|---|---|
| Testing | Flip the switch, listen | Run on manual | Water test on auto, flow overboard verified |
| Auto circuit power | Through the battery switch | Not checked | Bypasses the switch, fused near source |
| Connections | Taped splices in the bilge | Bare butt connectors | Sealed connections above the waterline where possible |
| Alarm | None | None | High-water alarm per ABYC |
| Result | Works until it doesn't | Works until the next storm | Verified automatic protection |