We will be sunsetting this online shop for our end customers (B2C) on Monday March 18th. Orders placed before this date will be processed as usual but you will not be able to track the order status online. Please check here for a list of Perkins parts distributors in your area to place your order with Perkins.

Should a fault occur, you may need to replace the fuel injectors on your Perkins engine to restore it to full working order and performance. Note that it is also recommended to change fuel filters whenever atomisers/nozzles are changed to ensure continued protection of the fuel system.

How to remove fuel injectors

Depending on the type of engine and injector you have, removal and assembly methods vary. Here is a typical change process:

Fuel injectors should only be removed if a fault with the injector occurs.


  • Remove the injector cover and remove the high-pressure fuel lines.
  • Disconnect the tube assemblies for the fuel filter base for the fuel inlet and outlet.
  • Remove the fuel hoses from the injector and remove the set screw and holding clamp.
  • Remove the injectors from the cylinder head.
  • Remove and discard the O-ring seal and seat washer from the injector. Note: if the original seat washer is not removed the injector will not be positioned correctly when a new injector with a seat washer is installed.


  • Ensure that the combustion sealing washer is installed correctly in the cylinder head and the O-ring is positioned correctly on the injector, before installing the injector.
  • Position the injector and tighten the clamp and setscrew before installing the hose lines and the fuel injection lines.
  • Re-install the cover and purge the air from the fuel system.

When replacing injectors, it is very important that dirt is not allowed to enter the fuel system. Before any removal action is taken, thoroughly clean around the fuel system component to be disconnected and fit a suitable cap or cover over all the disconnected fuel pipes and components.

Purging the system after a repair

If air enters the fuel system during a repair, it must be purged before the engine can be started. Air can also enter when:

    • The fuel tank is empty, or the tank has been partially drained.
    • The low-pressure fuel lines are disconnected.
    • A leak exists in the low-pressure fuel system.
    • The fuel filter is replaced.

It is important that you do not loosen the high-pressure fuel lines to purge air from the fuel system. Refer to your Operation and Maintenance Manual (OMM) for the correct procedure according to your engine type.

Visually inspect the high-pressure fuel lines for damage or signs of fuel leakage and replace any that have leaked. Ensure that all clips on the high-pressure fuel lines are securely in place. Always drain the water and the sediment from the fuel tank weekly daily to ensure that only clean fuel enters the fuel system.

Fuel system overview

Fuel injectors

Fuel injectors

Learn more

Fuel pumps

Fuel pumps

Learn more