The fuel pressure regulator will automatically compensate for restriction in the inline fuel filter, so the fuel pressure before the filter will be higher than observed rail/regulator fuel pressure. This increased fuel pressure is unnecessary load that can severely shorten the lifespan of your fuel pumps.
Stainless elements are somewhat forgiving because the inconsistencies in the mesh will allow some larger particles to pass. Stainless steel filter elements can be cleaned by backwashing it with fuel; however, ultrasonic is the best option. Ultrasonic filter can be purchased online, otherwise, local hydraulic supply stores can also provide filter cleaning as a service. Do not use acetone or any cleaner with acetone. (i.e. some brake parts cleaners have acetone) Lastly, please handle stainless elements gently and do not scrub the mesh with a brush, as it is delicate and could be damaged.
Microglass elements will require more frequent service and cannot be cleaned since the particles become embedded in the fibrous element. We recommend checking the pressure before and after the filter to determine the change interval unless you've already established change intervals from other cars using fuel from the same source with the same usage type.
Cellulose (paper) elements are generally best used for gasoline/race gas applications and can be changed annually. Since these are also fibrous, they are also disposable.
Fuel filter service interval depends on fuel maintenance, source, and environment, not directly based on time or mileage. As a starting point, here are some general guidelines for service:
- Gasoline fuel with any type filtration: change/clean filter annually (conservative)
- Ethanol blended fuel with stainless filter: clean annually
- Ethanol blended fuel with a microglass filter: monitor fuel pressure before and after the filter. If the difference exceeds 5 psi, replace the filter element
In case the filter elements are becoming clogged too quickly, we recommend changing fuel suppliers, switching to stainless filtration, and/or upgrading to 128mm long filter element.