Fuel Systems: Gasoline Fuel Systems: Fuel system procedure
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Topic IntroductionHelp

Replacing a fuel filter

Summary
There are two types of fuel filter: carbureted system filter and EFI system filter. It is important to follow the correct procedure for the type of vehicle you are servicing. The objective of this procedure is to show you how to remove and replace a fuel filter.

Part 1. Preparation and safety

Objective

Replacing a fuel filter

Personal safety

Whenever you perform a task in the workshop you must use personal protective clothing and equipment that is appropriate for the task and which conforms to your local safety regulations and policies. Among other items, this may include:

If you are not certain what is appropriate or required, ask your supervisor.

Safety check

New fuel filter

Points to note

Fuel lines

Clamp for flexible fuel lines


Part 2: Step-by-step instruction

  1. Locate fuel filter
    Refer to the vehicle service manual to identify the location and type of fuel filter, and the correct procedure for removing and replacing it.
  2. Remove static pressure from fuel system
    If the engine is fitted with an electric fuel pump, locate the fuel pump fuse using the service manual, and remove it. Start the engine and wait for it to stop as it runs out of fuel. Switch the ignition off.
  3. Obtain correct replacement
    Obtain the correct replacement filter and components. If the vehicle has a carbureted fuel system, new intake and outlet hoses may have been supplied with the filter. If so, then attach them to the new filter before you disconnect the old one.
  4. Using correct equipment, remove fuel filter
    Loosen the clamps on the fuel line on the engine side of the filter at the outer end of the hose and disconnect it. If necessary drain any excess fuel into the fuel proof container.
  5. Install carbureted system filter
    Connect the new filter hose and tighten the clamp. Make sure that you have the filter facing in the right direction, with the flow indicator arrow pointing towards the engine. Then remove the old filter and reconnect the new one to the fuel intake. If you do this quickly, very little of the residual fuel in the line should leak from the system.
  6. Remove old EFI system filter
    In a fuel injected system, the fuel is under greater pressure, so the fuel lines are normally made of metal, which are not replaced at the same time as the filter. Using the correct tool, loosen the metal line connectors and remove the filter, catching any leaking fuel in a fuel-proof container.
  7. Install EFI system filter
    Connect the new filter and tighten the line connectors. Make sure that you have the filter facing in the right direction, with the flow indicator arrow pointing towards the engine. Finally, remember to replace the fuel pump fuse.