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Long Beach Marine Electric connects boat owners with licensed, insured marine electricians for boat electrical repair at the slip: dead circuits, breakers that trip, gauges that read wrong, pumps and lights that work intermittently, and the burning smell nobody can trace. Repair starts with diagnosis. A voltage-drop test under load and a methodical circuit trace find the actual fault, whether it's a corroded crimp, a failed switch or a chafed wire, so you pay for one fix instead of a box of swapped parts.
What happens on the first visit
- A walk-through of the symptom with you: when it happens, what else is running, and whether it changed after recent work. Intermittent faults are found faster with a good history.
- Battery state and charging check first, because a weak bank causes symptoms that look like wiring faults.
- Voltage-drop measurement on the failing circuit under load, from the source through the breaker or fuse to the device and back on the negative side.
- Inspection of the connections the drop test points to: terminals, bus bars, crimps, switches and the backs of panels, where salt air does most of its damage.
- A written finding naming the faulty part or run, and a fixed price for the repair before work starts.
Why boat wiring fails in Long Beach's salt air
Most boat electrical faults aren't failed devices. They're resistance at a connection. Salt-laden marine-layer air works into crimps, terminal screws and bus bars, copper oxidizes, and resistance climbs. A connection that measured near zero when it was made can drop a volt or more under load a few seasons later. The device on the end of that circuit then runs dim, runs hot, or quits whenever the load peaks.
ABYC E-11 sets the targets that matter here: no more than 3% voltage drop on critical circuits such as navigation lights and bilge pumps, and no more than 10% on non-critical circuits. On a 12-volt boat, 3% is about a third of a volt. That's why a voltage-drop test under load, not a continuity beep, is the test that finds real faults.
The usual suspects on older boats
- Untinned automotive wire. Bare copper strands blacken inside the jacket, sometimes a foot or more from the visible end, so cutting back a few inches doesn't reach clean copper.
- Crimps without heat-shrink. Water wicks into the barrel and corrodes the joint from the inside.
- Overloaded circuits. Accessories added over the years to one breaker, with the wire never upsized.
- Chafe points. Wire runs through bulkheads and over engine brackets without grommets or support, where vibration wears through the insulation.
- Ground and negative-bus faults. A single bad negative connection can make several unrelated circuits misbehave at once.
When a repair becomes a rewire
On a 30- to 40-year-old boat, fixing one connection often exposes blackened wire behind it. The right call is to stop and price the choice: repair that run with tinned UL 1426 cable and sealed connections, or re-run the circuit. Electricians booked through Long Beach Marine Electric stop and call you before a job grows. If a pattern of failed runs shows up, a planned boat rewiring of the affected circuits costs less than chasing faults one by one.
A burning smell, melted insulation or a breaker that trips again immediately after reset is a fire risk. In BoatUS insurance claims, engine electrical faults cause about 20% of boat fires and other DC electrical faults another 15%. Leave that circuit off and call.
Insurance, warranty and who pays
Electrical repair is usually owner-paid. Insurance generally covers sudden damage, such as a fire, but not wear and corrosion. Diagnosis is billed hourly, typically $140–$200/hr in Long Beach with a one- to two-hour minimum, because nobody can know in advance how long a hidden fault takes to find. Once the fault is found, you approve a fixed price for the repair. See the marine electrician cost guide for typical totals.
What's included
- Symptom history and battery check
- Voltage-drop testing under load
- Positive and negative circuit tracing
- Connection, bus bar and switch inspection
- Tinned-wire splice and connection repair
- Breaker and fuse sizing check
- Written findings and fixed repair price
- Re-test of the repaired circuit
DIY vs cheap fix vs proper electrical repair
| Factor | DIY | Cheap operator | Proper marine work |
|---|---|---|---|
| Diagnosis | Swap parts until it works | Replace the obvious part | Voltage-drop test under load, then fix |
| Wire | Hardware-store copper | Automotive, untinned | Tinned UL 1426 marine cable |
| Connections | Twist-on nuts and tape | Bare crimps | Ratcheting crimps + adhesive heat-shrink |
| Circuit protection | Often skipped | Sized to the load | Sized to the wire, per ABYC E-11 |
| Result | Fault returns | Fault moves | Drop within 3% / 10% limits |