# Duffy Electric Boat Repair | Battery Packs & Chargers | Long Beach Marine Electric

> Duffy electric boat repair in Long Beach and Newport Beach: battery pack replacement, chargers, controllers and motor wiring. Free estimate. Call today.

URL: https://longbeachmarineelectric.com/duffy-electric-boat-repair/

Repair · Same-day callback

# Duffy Electric Boat Repair & Battery Packs

Battery packs that won't hold a charge, chargers that quit, controllers and motor wiring, for Duffys and other electric harbor boats.

[Call (562) 374-7233](tel:+15623747233) [Get a Free Estimate](/contact/)

-   Battery pack replacement
-   Pack balancing & cell testing
-   Onboard charger diagnosis
-   Motor controller & throttle wiring
-   Lithium pack upgrades
-   Free estimate within 24 hours

Last updated: October 6, 2026

[Long Beach Marine Electric](/) connects owners with licensed, insured marine electricians for Duffy electric boat repair: replacing tired battery packs, diagnosing chargers and controllers, and repairing motor and throttle wiring. Duffy boats began in Newport Beach. The company's founder built the first prototype in 1966, and an OCBJ report counted about 2,200 Duffys in Newport Beach alone. Their quiet, simple electric drives depend almost entirely on a healthy battery pack and charger.

## What happens on the first visit

1.  Pack voltage at rest and under load, then each battery tested individually. One weak battery drags the whole pack down.
2.  Charger check on shore power: is it delivering current, and does it finish the charge cycle?
3.  Inspection of the pack interconnect cables and terminals, where corrosion and loose connections cause heat and voltage drop.
4.  Controller, throttle and motor wiring check if the boat runs poorly, not just briefly.
5.  A written finding and a fixed price, with options for lead-acid or lithium replacement packs.

## Why electric boats lose range

Duffy's own guidance puts typical battery-pack life at **over 800 cycles** with proper maintenance, and as many as about 1,200. Packs fail for the same reasons as any lead-acid bank: age, chronic undercharging, low electrolyte in flooded batteries, and one weak battery in a series pack pulling the others down. A boat that used to cruise the harbor all afternoon and now needs charging after an hour usually has a tired pack or a charger that no longer finishes its cycle. Duffy says a full charge typically takes about 12 hours.

## Pack replacement: like-for-like or lithium

A like-for-like lead-acid pack is the lowest-cost fix and keeps the boat's existing charger and controller settings. A lithium pack cuts weight substantially, holds voltage better through the run and lasts many more cycles, but the charger, and sometimes the controller, must be set up for it. Either way, the whole pack is replaced together and the interconnects renewed. See [lithium conversion](/lithium-battery-conversion/) for how lithium systems are designed.

## Chargers, controllers and wiring

Electric harbor boats sit plugged in for long periods, so the onboard charger is working constantly. Chargers fail, and some older units never finish a full charge, which slowly sulfates the batteries. Motor controllers and throttle wiring fail less often, but corrosion at connectors in the bilge and stern compartment is common in salt water. Most diagnosis and pack work is done at the dock.

## Insurance, warranty and who pays

Electric boat repairs are owner-paid, or billed to the rental or fleet operator. Pack diagnosis usually takes about an hour. A pack replacement is priced in writing with the batteries, interconnects and labor itemized before work starts.

## What's included

-   Pack and individual battery testing
-   Battery pack replacement
-   Interconnect cable renewal
-   Charger diagnosis and replacement
-   Lithium pack upgrade option
-   Controller and throttle wiring check
-   Motor connection inspection
-   Fleet and rental service

## DIY vs cheap fix vs proper electric boat repair

DIY

Cheap operator

Proper marine work

Diagnosis

Replace the charger

Replace the worst battery

Every battery tested under load

Pack

Mixed old and new

Partial replacement

Full matched pack

Interconnects

Reused

Reused

Renewed with sealed terminals

Charger

Not checked

Not checked

Full cycle verified, profile matched

Result

Short range continues

Range fades again

Range restored and verified

## Sources

-   [Duffy Boats: about Duffy (history and battery packs)](https://www.duffyboats.com/about/)
-   [OCBJ: Duffy electric boats in Newport Beach](https://www.ocbj.com/tourism/slow-ride/)

Boat won't hold a charge?

Get the pack tested at the dock. Same-day callback.

[(562) 374-7233](tel:+15623747233)

Mon–Sat 7am–6pm · Free estimate within 24 hours

Standards applied

-   ABYC E-10 (batteries)
-   ABYC E-11 (DC systems)
-   ABYC E-13 (lithium)
-   Charger profile matched to chemistry

[Estimate your cost](/tools/marine-electrical-cost-estimator/)

How it works

## How duffy electric boat repair works

1.  01
    
    ### Tell us the symptom
    
    Short range, won't charge or won't run. Same-day callback.
    
2.  02
    
    ### Test the pack
    
    Each battery tested; charger and interconnects checked.
    
3.  03
    
    ### Fixed price
    
    Lead-acid or lithium options priced in writing.
    
4.  04
    
    ### Charge & run test
    
    Full charge cycle confirmed and the boat test-run.
    

Get duffy electric boat repair at your slip today

Same-day callback. Written price before any work.

[Call (562) 374-7233](tel:+15623747233) [Get a Free Estimate](/contact/)

Straight answers

## Duffy Electric Boat Repair questions

### How long do Duffy battery packs last?

Duffy's guidance is over 800 cycles with proper maintenance, sometimes up to about 1,200. Chronic undercharging and low electrolyte shorten that.

### Can I replace just one bad battery in the pack?

It's not recommended. A new battery in an old series pack is pulled down to the others' level. Replace the whole pack for reliable range.

### Can I convert my electric boat to lithium?

Usually yes, with a charger set for lithium and sometimes controller changes. It cuts weight and extends pack life significantly.

### Do you service rental and fleet electric boats?

Yes. Fleet operators can schedule pack testing and replacements across several boats to minimize downtime.

### Who does the work, and how do I know they’re qualified?

Long Beach Marine Electric is a free service that connects you with an independent, licensed and insured marine electrician who holds the American Boat & Yacht Council (ABYC) Marine Electrical Certification. Ask your electrician for proof of license and insurance before work starts.

## Related services

[Marine Battery InstallationBatteries keep dying, or the charger won't charge on shore power? Covers battery banks, chargers, switches and parasitic-draw testing.](/marine-battery-installation/) [Lithium Battery ConversionLiFePO4 house banks installed to ABYC E-13, with matched chargers, alternator regulation, DC-DC charging and BMS integration.](/lithium-battery-conversion/) [Boat Electrical RepairDead circuits, flickering panels, intermittent faults. A dockside electrician traces the fault with a meter and a voltage-drop test, then fixes it at your slip.](/boat-electrical-repair/)

Get your electric boat's range back

[Call (562) 374-7233](tel:+15623747233) [Get a Free Estimate](/contact/)