Cummins N4100040 Fuel Transfer Pump Unit

Module Feature

N4100040 is Cummins original diaphragm fuel transfer pump. It is driven by engine camshaft, adopting rubber diaphragm reciprocating movement to realize fuel suction and delivery.

It provides stable low-pressure fuel supply for high-pressure injection pump, with built-in check valve to prevent fuel backflow. The pump body has good oil resistance and vibration resistance, suitable for continuous operation of industrial diesel engine and generator set.

Working principle

Camshaft pushes the rocker arm to drive diaphragm reciprocating deformation. When diaphragm lifts, negative pressure is formed inside pump chamber, fuel is sucked from fuel tank through inlet check valve.

When diaphragm compresses, internal pressure rises, inlet valve closes, outlet check valve opens and fuel flows to filter and high-pressure injection pump. Once diaphragm ruptures, fuel supply will be interrupted.

Onboard components

Cast aluminum pump housing, rubber diaphragm, rocker arm assembly, return spring, inlet and outlet one-way check valves, sealing gaskets, mounting flange.

LED indicators

No built-in indicator lamp. Fuel supply fault status is displayed on engine controller panel.

Hardware self‑diagnosis

No electronic self-test for pump itself. ECU judges fuel supply abnormality through rail pressure deviation and engine speed fluctuation.

Programming software

Cummins INSITE software for reading fuel pressure data and related fault codes.

Electrical & Process Parameters

Model:N4100040 Brand:Cummins Device type:Diaphragm Fuel Transfer Pump Media:Diesel fuel Drive:Engine camshaft mechanical drive Function:Low pressure fuel suction and delivery for diesel engine fuel system

Mechanical & Structure

Mounting:Bolted on engine block Protection class:IP54 Housing:Cast aluminum pump body

Environmental

Operating temperature:-40℃ ~ +120℃ Storage temperature:-40℃ ~ +85℃ Ambient humidity:5~95% non‑condensing Certification:Cummins OEM engine standard compliant Status:Cummins original fuel pump spare

Installation

Clean mounting surface before installation, replace new sealing gasket, tighten pump fixing bolts to specified torque.

Connect fuel inlet and outlet pipelines according to marking direction. After assembly, perform priming and leakage test. Regularly check diaphragm for aging and fuel leakage.

Interface

Fuel inlet port, fuel outlet port, cam drive rocker contact end, mounting bolt holes.

Diagnostic

Engine power insufficient: Diaphragm fatigue damage, check valve stuck, insufficient fuel delivery.

Fuel leakage: Diaphragm rupture, gasket loose.

No fuel delivery: Rocker arm worn and cannot drive diaphragm movement.

Product BriefCummins N4100040 mechanical diaphragm fuel transfer pump, cam driven, self-priming, used for diesel engine low-pressure fuel supply.