How to Make a Portable 12v Fuel Transfer Pump

Introduction

In this tutorial, we'll guide you through the process of making a portable 12v fuel transfer pump. This DIY project is particularly useful for those who need to transfer fuel, especially in situations where traditional filling methods are inconvenient, such as fueling a boat with a gas and oil mixture. By creating your own pump, you can ensure reliability and avoid the pitfalls of low-quality commercial options.

Step 1: Gather Your Tools and Supplies

Before you start building your fuel transfer pump, make sure you have the following tools and materials:

• Soldering iron
• Solder
• Heat shrink tubing
• Heat gun
• Wire cutters
• Wire
• Cigarette lighter plug
• Fuel pump
• Fuel hose
• Hose clamps
• Brass sintered filter
• Switch

Step 2: Prepare the Fuel Pump Wiring

1. Strip the Wires: The fuel pump has two wires:
   • Black wire for ground
   • Brown wire for power
2. Cut the Cigarette Lighter Wire: Remove the connector from the cigarette lighter wire.
3. Identify the Wires: Use a multimeter to determine which wire from the cigarette lighter is ground (outer contact) and which is power (center pin).
4. Strip the Wires Again: Prepare the wires from both the fuel pump and the cigarette lighter plug.

Step 3: Solder the Connections

1. Apply Heat Shrink: Place heat shrink tubing on both the ground and power wires.
2. Twist and Solder: Twist the corresponding wires together and solder them. If you're unfamiliar with soldering, consider watching a tutorial for guidance.
3. Allow Cooling: Let the soldered connections cool before moving on to avoid premature shrinking of the tubing.
4. Heat Shrink Application: Use the heat gun to shrink the tubing around the soldered connections securely.

Step 4: Install the Switch

1. Separate the Molded Wire: Carefully use a razor knife to separate the molded wire without damaging the insulation.
2. Disassemble the Switch: Use a screwdriver to take apart the switch.
3. Route the Wires: One wire should go inside the switch case while the other connects to the switched part of the circuit.
4. Clip the Power Wire: Cut the power wire to ensure the switch controls the circuit effectively.
5. Reassemble the Switch: Put the switch back together, ensuring the wires are properly seated.

Step 5: Extend the Wiring

1. Prepare Additional Wire: If needed, install an extension wire to reach your cigarette lighter port.
2. Strip, Solder, and Shrink: As before, strip the insulation, solder the connections, and apply heat shrink tubing.

Step 6: Assemble the Fuel Lines

1. Attach Hose Barb: Ensure the hose barb fittings have sealant on the threads.
2. Clamp the Hoses: Use a single ear clamp to secure the hoses, ensuring a tight fit.
3. Install the Brass Sintered Filter: Attach this filter to the suction line to prevent debris from entering the pump.
4. Connect the Supply Line: This line should be longer to reach the boat’s fuel tank filler.

Step 7: Test Your Pump

1. Initial Test: Connect the pump to a fuel can and plug it into the vehicle’s cigarette lighter for a preliminary test.
2. Boat Test:
   • Ensure the suction line is in the fuel tank with the filter attached.
   • Insert the filler line into the fuel cap of your boat.
   • Use the rotary switch to turn the pump on and off.

Conclusion

You've successfully built a portable 12v fuel transfer pump! This setup allows for efficient and reliable fuel transfers, especially for your boat. Always remember to test your pump before use and ensure all connections are secure. For future projects, consider exploring additional DIY tutorials for enhancing your boating experience. Happy DIYing!