Lift Pump Block-Off Plate – Small Part, Big Purpose
Seal off your engine's mechanical lift pump port with a precision-fit block-off plate. Ideal for electric fuel system upgrades, it prevents leaks and keeps your engine bay clean.
When upgrading an engine for better power or reliability, even small parts matter. One such overlooked but important component is the lift pump block-off plate. Designed to cover the opening left when removing a mechanical lift pump, this simple plate becomes a key upgrade in new diesel builds.
Why Remove the Mechanical Lift Pump?
Older diesel engines, like those in Mercedes OM605, OM606, and others, use hand pumps to push fuel from the tank to the injection system. But when switching to an electric fuel pump for improved control and flow, the hand pump is no longer needed. Removing it leaves an open spot on the engine block that must be sealed correctly.
What Does a Block-Off Plate Do?
That’s where the cover plate comes in. Made to match factory specifications, it fits right in place of the old pump using the same screws. Once installed, it prevents oil leaks, keeps dirt out, and maintains internal pressure. Usually made from materials like aluminum or steel, it is both durable and heat-resistant.
Materials and Construction Matter
High-quality block-off plates are often manufactured with CNC machines for precise fitting. Aluminum and stainless steel are popular choices due to their strength, corrosion resistance, and ability to withstand engine heat. A proper seal also requires a good gasket or O-ring to ensure leak-free operation under pressure.
Installation Made Simple
Installing a lift pump block-off plate is straightforward. Most plates just bolt on using existing hardware. With common tools and proper alignment, the entire process can be completed in just a few minutes, making it one of the easiest yet most essential steps in upgrading your fuel system.
Final Thoughts
Whether you’re building a race car, restoring a street vehicle, or updating an old diesel, the lift pump block-off plate is a smart and necessary addition. It’s a small part with big benefits—keeping your engine safe and completing your build effectively.