Recommended Parts Needed to Convert Boat Trailer from Hydraulic to Electric Drum Brakes
Question:
Vintage Escort / Calkins build 3500lb dual axle boat trailer conversion from hydraulic to electrical brakes. Please respond and I send you some pictures. Nothing but virtual hugs Hans the farmer in Asheville NC.
asked by: Hans H
Helpful Expert Reply:
Electric drum brakes are being found on boat trailers more and more these days since they are generally more cost-effective and easier to install than hydraulics.
Converting your tandem axle Calkins trailer from hydraulic to electric drum brakes means you'll no longer need brake lines or a surge coupler. You can keep your existing coupler if you like but you'll need to drill a hole through it side to side and install a bolt and nut to immobilize it. If you prefer you can install a new fixed coupler. Our main page for couplers is linked for you and this shows straight-tongue couplers like Fulton # F346000301 and a-frame types such as Bulldog # BD43805W0317.
Your 3500-lb axles will typically be fitted with 10-inch diameter x 2-1/4-inch wide brakes such as those shown on the linked page, like Dexter # AKEBRK-35R-SA right-hand brake and left-hand # AKEBRK-35L-SA. You will want to check your hub/drum size to make sure you select compatible brakes. The linked article on adding electric brakes to a trailer includes a diagram on how to measure your drums, as well as lots of other great info that applies to your project. Electric brakes are not polarized so you can use either wire as ground and hot.
You also want to select brakes that use the same mounting hole pattern as your old ones. All 3500-lb brakes we offer use a 4-bolt pattern like that on the brakes referenced above.
You will also need to wire your vehicle with a 7-way type connector and a brake controller like the excellent Prodigy P3 # 90195. Brake controllers are not vehicle-specific but their installations vary depending on how the vehicle is equipped. In a vehicle with only a 4-pole harness you'll use our brake controller installation kit # ETBC7 which includes everything needed to hardwire a controller like the P3. The kit includes the vehicle 7-way socket, wiring, connectors, circuit breakers, etc.
You will also need to install a 7-way trailer plug on the trailer, such as # H20046 from Hopkins. This is easiest by using a junction box like # 38656 which allows for convenient splicing together of the existing trailer wiring and the new 7-way plug. You'll also need ring terminals on both ends of the wiring to join them inside the junction box. Use part # DW05702-1 for the 14 to 16-gauge lighting wires and part # 44-5310A for the 12V power, ground and brake circuit. You'll also use 10-gauge wire # 10-1-1 to run the brake circuit on the trailer.
Products Referenced in This Question
Ring Terminal - 12-10 Gauge Wire - 3/16" Ring ID
- Wiring
- Wire Connectors
- Ring Terminals
- 3/16 Inch Diameter
- 12-10 Gauge
- Flint Hill Goods
more information >
Tekonsha Prodigy P3 Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Electric over Hydraulic
- Automatic Leveling
- Under-Dash Box
- Dash Mount
- Up to 4 Axles
- LCD Display
- Up to 360 Degrees
- Tekonsha
more information >
Electric Trailer Brake Assembly - Self-Adjusting - 10" - Left Hand - 3,500 lbs
- Accessories and Parts
- Trailer Brakes
- Electric Drum Brakes
- LH
- 3500 lbs
- Brake Assembly
- Self Adjust
- 10 x 2-1/4 Inch Drum
- etrailer
more information >
Electric Trailer Brake Assembly - Self-Adjusting - 10" - Right Hand - 3,500 lbs
- Accessories and Parts
- Trailer Brakes
- Electric Drum Brakes
- RH
- 3500 lbs
- Brake Assembly
- Self Adjust
- 10 x 2-1/4 Inch Drum
- etrailer
more information >
Bulldog Heavy-Duty Cast Head Coupler w/ Wedge Latch - 2" Ball - A-Frame - 8,000 lbs
- A-Frame Trailer Coupler
- Standard Coupler
- Weld-On
- 8000 lbs GTW
- 2 Inch Ball Coupler
- Trigger Latch
- Bulldog
more information >
Ring Terminal -16-14 Gauge - 1/4" Ring ID - Qty. 1
- Wiring
- Wire Connectors
- Ring Terminals
- 1/4 Inch Diameter
- 16-14 Gauge
- Deka
more information >
Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
- Accessories and Parts
- Trailer Brake Controller
- Installation Kits
- etrailer
more information >
Fulton Fas-Lok Coupler - 2" Ball - 3" Channel - 6,000 lbs
- Straight Tongue Trailer Coupler
- Standard Coupler
- 2 Inch Ball Coupler
- Bolt-On
- 6000 lbs GTW
- 3 Inch Channel
- Trigger Latch
- Fulton
more information >
Hopkins 7-Way RV Style Connector with Molded Cable - Trailer End - 8' Long - RV Standard
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 6 - 10 Feet Long
- Plug and Lead
- 7 Round - Blade
- Hopkins
more information >
Product Page this Question was Asked From
Tekonsha Prodigy P2 Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Electric over Hydraulic
- Automatic Leveling
- Under-Dash Box
- Dash Mount
- Up to 4 Axles
- LED Display
- Up to 360 Degrees
- Tekonsha
more information >
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Instructions
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