CarBole 12V Diesel Electric Fuel Pump Super 12D — 35 GPH, 5–9 PSI, 5/16-inch fittings

The CarBole Super 12D is a compact 12‑volt diesel fuel pump delivering 35 GPH at 5–9 PSI for carbureted 4, 6, and 8‑cylinder engines and for fuel transfer or boosting when mounted correctly.

This rugged electric pump is built for diesel applications where a steady low pressure and dependable flow are required. Engineered as a universal replacement for carbureted systems and as a transfer booster, the unit combines a durable motor with 5/16" inlet and outlet fittings so it integrates easily with standard fuel hoses. It is not compatible with fuel‑injected systems or aggressive fuels such as ethanol blends or methanol; use only diesel to preserve internal components.

How does this pump support carbureted diesel engines and fuel transfer?

The Super 12D supplies a consistent low-pressure flow that helps protect carburetor operation and reduces vapor lock and stalling. Its 35 GPH capacity gives enough volume for small engine fueling or rapid tank transfers while the 5–9 PSI range keeps pressure appropriate for gravity-fed and carbureted setups.

• Flow rate: 35 gallons per hour for steady delivery
• Operating pressure: 5–9 PSI suitable for carburetor systems
• 5/16" inlet/outlet fitting fits standard fuel hose I.D.
• Can be used as a booster or transfer pump when installed correctly

What are the installation and mounting requirements?

Install the pump within 12 inches of the fuel tank as recommended to ensure reliable suction and to prevent cavitation. The compact housing and standard 5/16" connections make plumbing and wiring straightforward for most DIY installations, but avoid placing the pump where it will be submerged or exposed to incompatible liquids.

• Mounting: within 12 inches of the fuel tank for optimum suction
• Hose size: 5/16" I.D. recommended for inlet and outlet
• Electrical: 12‑volt DC supply required with appropriate fuse
• Do not mount on fuel-injected systems or use with ethanol blends

Which engines and fuel types are appropriate for this pump?

This unit is intended for diesel‑only, carbureted engines—commonly found in older tractors, generators, and small industrial equipment with 4, 6, or 8 cylinders. It is not engineered for fuel injection pressures nor for corrosive fuels, so using anything other than diesel risks internal damage and voids suitability.

• Compatible: diesel, carburetor-fed 4/6/8‑cylinder engines
• Not compatible: fuel-injected systems or high-pressure injection rails
• Not suitable: E85, ethanol blends, methanol, or corrosive liquids
• Typical uses: transfer, boosting, or replacement in carbureted equipment

How does the pump prevent common fuel delivery problems?

By producing a controlled low pressure and reliable flow, the pump helps minimize vapor lock and flooding that can plague carbureted diesel systems. Correct placement and proper hose routing further reduce air ingestion and ensure steady supply during varying engine loads.

• Reduces vapor lock risk with steady low PSI output
• Helps avoid flooding by matching carburetor demand
• Compact design lessens heat exposure and prolongs motor life
• Simple plumbing reduces potential leak points

Who this is for: The CarBole Super 12D is aimed at owners and technicians of older diesel equipment, hobbyists restoring carbureted diesel engines, and anyone needing a compact, low‑pressure transfer or booster pump for diesel fuel. If you have a carburetor-fed 4, 6, or 8‑cylinder diesel engine or require a portable pump for moving diesel fuel, this unit provides a cost-effective, straightforward solution—provided you stick to approved fuel types and mounting recommendations.