VDO Reed Switch Fuel Sender - 400 MM

The VDO Reed Switch Fuel Sender – 400 MM is a marine fuel tank sender designed to eliminate the erratic gauge readings common to traditional swing-arm float designs. Unlike conventional fuel senders that rely on rotating arms and resistance cards, this reed switch model uses a sealed, non-moving electrical contact system. The 400 MM length suits applications where a conventional swing-arm design cannot fit due to tank geometry or clearance constraints. This is especially valuable in custom-built boats, retrofit installations, and tight fuel tank configurations where space is premium.

The reed switch mechanism operates without mechanical friction, meaning the sender has no moving parts to wear out or corrode—a critical advantage in saltwater environments where moisture ingress accelerates failure. The tubular design acts as a natural dampener, preventing fuel slosh from causing wild pointer swings on the gauge during acceleration, deceleration, or rough seas. This stability matters most when monitoring fuel consumption on long offshore runs or when fuel levels are critical to trip planning. The sealed construction protects internal contacts from salt spray and condensation, extending service life in marine conditions where exposure to corrosive salt air is constant.

This sender is ideal for boaters, fishermen, and marine technicians working on fuel system upgrades, tank replacements, or custom installations. Weekend anglers appreciate the stable, accurate readings for trip planning, while serious offshore operators value the reliability of a sealed, non-mechanical design for extended time at sea. The compact, corrosion-resistant construction suits both freshwater and saltwater applications. VDO's engineering reputation in marine instrumentation backs the design, making this sender a practical choice for anyone replacing a failing fuel sender or upgrading from outdated swing-arm technology.