Fuel Filter 3/8 Inline

3/8-Inch Inline Fuel Filter for Auxiliary Diesel Tank Systems

This compact inline fuel filter provides an additional layer of protection for compatible auxiliary diesel-tank and low-pressure fuel-transfer systems.

Installed in a 3/8-inch fuel hose, the filter captures dirt, rust, scale and other solid contamination before it can reach the transfer pump, vehicle fuel tank or downstream filtration system. Its durable metal housing contains a cellulose filter element rated at 99% efficiency at 22 microns.

This filter is particularly useful in auxiliary-tank installations, where contamination can enter through fuel filling, condensation-related tank corrosion, ageing hoses or debris already present inside the tank.

This product is supplied unfitted.

Key Features

• Compact inline fuel filter
• Suitable for compatible auxiliary diesel-tank installations
• Designed for low-pressure fuel-transfer lines
• 3/8-inch fuel-line connections
• Approximately 9.5mm inlet and outlet size
• 99% filtration efficiency at 22 microns
• Cellulose filter media
• Durable metal outer housing
• Helps capture dirt, rust, scale and other solid particles
• Helps protect transfer pumps and downstream fuel-system components
• Disposable service filter
• Compact 99mm overall length
• Supplied unfitted

Why Install an Inline Fuel Filter?

Fuel can collect contamination during transport, storage and filling. Auxiliary tanks may also accumulate particles from manufacturing residue, ageing internal surfaces, damaged filler components or contamination introduced through fuel containers.

Without an inline filter, this material can travel through the fuel system and contribute to:

• Restricted fuel flow
• Transfer-pump wear or failure
• Blocked hoses and fittings
• Premature loading of the vehicle’s main fuel filter
• Fuel-delivery faults
• Reduced engine performance
• Damage to sensitive downstream fuel-system components

Installing a serviceable filter close to the auxiliary tank allows larger contamination to be collected before it travels farther through the system.

Protection for Auxiliary Fuel Systems

This filter is well suited to a compatible low-pressure fuel line between an auxiliary diesel tank and its transfer pump or fuel-transfer connection.

Positioning the filter upstream of the pump can help prevent solid debris from entering and wearing the pump mechanism. The exact position must suit the pump manufacturer’s requirements, available fuel flow and the design of the complete installation.

22-Micron Filtration

The filter provides 99% efficiency at 22 microns. This allows it to capture common solid contamination while maintaining fuel flow through a correctly sized low-pressure system.

Its filtration level makes it suitable as a supplementary primary filter or pre-filter. It does not replace the vehicle manufacturer’s finer final-stage diesel filter.

Cellulose Filter Media

The internal cellulose media provides a large filtering surface within the compact housing. As fuel passes through the element, solid contamination is retained within the media rather than continuing through the fuel line.

The element is not designed to be washed or reused. The complete filter should be replaced once it reaches its service interval or shows signs of restriction.

Metal Housing

A metal outer housing protects the filter element and provides a compact, robust component for a correctly supported vehicle fuel-line installation.

The filter must still be mounted away from:

• Exhaust components and excessive heat
• Sharp edges
• Moving suspension or driveline components
• Direct impact from stones or debris
• Locations where the housing may be crushed

3/8-Inch Fuel-Line Connections

The filter is designed for compatible 3/8-inch fuel hose, equivalent to approximately 9.5mm internal diameter.

Both hose connections must be secured with suitable fuel-rated clamps. The hose must be compatible with diesel fuel and should not be cracked, hardened, swollen or otherwise deteriorated.

Why the Filter Must Be Replaced

A fuel filter collects contamination rather than removing it from the system permanently. As more material becomes trapped, the filter gradually becomes restricted.

Continuing to use a heavily contaminated filter can cause:

• Reduced fuel-transfer speed
• Transfer-pump noise or overheating
• Increased load on the fuel pump
• Intermittent fuel delivery
• Hard starting or loss of engine power where the filter is part of the engine supply line
• Complete blockage of the fuel system

Replacing the filter before it becomes heavily restricted helps maintain reliable fuel flow and reduces unnecessary load on the pump.

Recommended Replacement Interval

The correct replacement interval depends on fuel quality, tank condition, installation layout and how frequently the auxiliary tank is used.

Where the vehicle or auxiliary-tank system does not specify a different interval, the following provides a practical service guide:

• Inspect the filter, hoses and clamps at every vehicle service
• Replace the filter approximately every 20,000km in a regularly used auxiliary diesel system
• Replace it sooner when regularly filling from remote or uncertain fuel sources
• Replace it immediately after known or suspected fuel contamination
• Replace it if fuel-transfer speed decreases or the pump begins operating differently
• Carry a spare filter during remote-area or extended overland travel

The vehicle, engine or auxiliary-tank manufacturer’s specified service interval takes priority where one is provided.

Signs That Replacement May Be Required

• Slower-than-normal transfer from the auxiliary tank
• Transfer pump running louder than usual
• Pump repeatedly cycling or struggling to maintain flow
• Visible contamination during fuel-system servicing
• Hard starting
• Engine hesitation or loss of power under load
• Fuel-starvation symptoms
• Recent use of contaminated or questionable fuel
• Long-term storage of fuel in the auxiliary tank

These symptoms can also be caused by other fuel-system faults and should be investigated rather than assuming the filter is the only cause.

Suitable Applications

• Auxiliary diesel fuel tanks
• Low-pressure diesel transfer systems
• Fuel-transfer pump inlet protection
• Truck and four-wheel-drive auxiliary fuel installations
• Motorhome and expedition-vehicle fuel systems
• Agricultural and industrial equipment using a compatible 3/8-inch low-pressure fuel line

Specifications

Included

• 1 x 3/8-inch inline fuel filter

Important Note

This filter is intended for a compatible low-pressure fuel line. It must not be installed on the high-pressure side of a common-rail diesel injection system.

This is a particulate filter and is not a water separator. Where water contamination is a concern, a suitable diesel fuel filter and water-separator system should also be used.

The filter supplements the vehicle’s original fuel filtration and does not replace the factory final-stage diesel filter.

Fuel hose, clamps, mounting hardware and other installation components are not listed as included.

Confirm the required hose size, fuel compatibility, flow direction and available mounting space before installation. After fitting, prime the system where required and check every connection carefully for fuel leaks before operating the vehicle or transfer pump.