Duffy Electrical Repairs
A Duffy is an electric boat — when the wiring gets tired, everything goes wrong at once. We trace faults properly with meters and load tests instead of throwing parts at the problem and hoping.
Salt air is relentless on connections. By the time a Duffy is eight or ten years old, the terminals are green, the cable ends are corroded under the insulation where you can't see them, and the whole system is losing voltage everywhere at once. That shows up as short run time, a charger that never seems to finish, and lights that dim when the motor loads up. Almost always it's connections, not components.
What's included
- Full system test: batteries, charger, controller, motor, and shore power
- Voltage-drop testing under real load, not just at rest
- Corroded terminal, lug, and cable replacement
- Charger and shore-power troubleshooting and replacement
- Motor controller and throttle diagnostics
- Nav lights, courtesy lights, stereo, and bilge pump circuits
- Helm switch panels rebuilt or replaced
- Circuits brought up to ABYC standards with correct fusing
The usual suspects
Green terminals and voltage drop
The single most common fault we find. Each corroded connection costs you a fraction of a volt, and a Duffy has a lot of connections. Add them up and the motor sees meaningfully less than the bank is actually holding.
A charger that never finishes
Either the charger has failed, or its profile doesn't match the batteries it's charging — which happens constantly after a battery swap where nobody changed the setting. Both are cheap to diagnose and expensive to ignore, because the wrong profile quietly destroys a new bank.
Pumps and lights on the wrong circuit
Bilge pumps wired downstream of a switch panel stop working the moment someone turns the master off. We rewire pumps to a dedicated, always-live, properly fused feed the way they should have been from the start.
Motors and controllers
We work on the whole drivetrain, not just the wiring up to it — motor brushes and bearings, controllers, throttle assemblies, and the interlocks between them. If a controller genuinely needs replacing, we'll show you the readings that say so.
Boat dead in the slip? Call us — a no-power Duffy is usually a same-week visit, and often a same-visit fix.
Typical pricing
| Work | Rate |
|---|---|
| Diagnostic visit (first hour) | $145 |
| Shop rate thereafter | $125 / hr |
| Terminal & cable rebuild (per bank) | $180–420 |
| Charger replacement, installed | $560–1,150 |
| Helm panel rebuild | $380–900 |
| Full rewire, Duffy 18–22 | $2,400–4,800 |
The diagnostic hour is credited against the repair if you go ahead with the work. Parts are billed at cost plus 15%.
How it works
Four steps, no surprises on the invoice
Diagnose
Load test, voltage drop under load, and a thermal check of the connections that are working hardest.
Report
You get the actual readings and what they mean, in language that doesn't require an electrician to interpret.
Repair
Replace, re-terminate, re-route, and fuse correctly — with tinned marine cable and heat-shrink lugs throughout.
Verify
Full run-up and a sea trial, so the fix is proven on the water and not just on the bench.
Common questions
Electrical Repairs, answered
Can you come to my slip?
Yes — most electrical work happens dockside anywhere in our service area. Only full rewires and motor removal need the boat in the yard.
My run time dropped. Is that the batteries or the wiring?
Usually both, and it's worth finding out which is leading. We load test the bank and measure drop across the cabling in the same visit, so you're not paying for a new bank that a $200 cable rebuild would have fixed.
Do you work on non-Duffy electric boats?
Yes. Duffys are most of what we see, but the same testing applies to any 48V electric drivetrain.
Will you bring the boat up to code?
We wire to ABYC standards as a matter of course. If we find something genuinely unsafe elsewhere on the boat, we'll flag it — whether or not it's part of the job you called about.
Ready when you are
Tell us your boat and your harbor, and we'll come back with a free written estimate — usually within one business day.