Heavy Duty Air Filters
Frequently Asked Questions
Q: Why am I experiencing short air filter life?
A: The amount of dirt an air filter can hold before servicing depends on many variables. The environment must be considered (severe dust, soot, moisture etc.) as it is crucial to know how much contaminant reaches the filter. This would depend on the severity of the environment and whether the air cleaner is a one or two stage design. Another factor is the size of the air cleaner and filter relative to the airflow requirement. How long a filter lasts is largely a function of the Original Equipment manufacturer’s intake design.
Reference FMC TSB 89-3R3 and 06-2 for further details.
Q: What is the micron rating of my air filter?
A: Typically, air cleaners and air filters are not assigned a “micron rating.” Micron rating is a term used in liquid filtration. Air filters are evaluated for efficiency using an industry-wide standard ISO 5011. Efficiency is the percentage of contaminant that a filter removes from the intake air relative to its capacity.
Reference FMC TSB 04-3 for further details.
Q: What do inches or millimeters of H2O have to do with an air cleaner?
A: In an intake filtration system the resistance to airflow is called restriction. Restriction is typically measured in units called inches or millimeters of H2O vacuum and is defined as the difference in static pressure between the atmosphere and the outlet side of the system being measured. The higher the restriction the harder an engine has to work to obtain clean air for combustion. Engine manufacturers specify a restriction level at which the air filter should be serviced.
Reference FMC TSB 89-3R3 for further details.
Q: Why do some air filters require U.L. approval?
A: Some engine air filters utilize flame retardant filter media to meet UL safety requirements. The U.L. rating covers fire safety and backfire resistance aspects of industrial trucks with internal-combustion engines, such as tractors, platform-lift trucks, fork-lift trucks, and other specialized vehicles for industrial use. These requirements do not cover other possible safety aspects of such equipment. Additional information can be found in UL 558 specification.
Q: Scavenged intake systems function/application?
A: Some intake system pre cleaners are inertial separating devices that require a scavenge flow of air to function properly. The scavenge flow is required to expel the inertially separated dust particles from the pre cleaner assembly. Scavenge flow is typically provided by a vacuum from an exhaust ejector that may be designed in as a function of the exhaust system muffler or as an add on exhaust ejector stack. Reference manufacturers published information for application and installation recommendation guidelines.
Q: Pre cleaner function/application? What type is best for a given application?
A: Intake system pre cleaners are typically inertial separating devices intended to work in conjunction with the air cleaner to clean intake air prior to the final filtration stage provided by the filter element. Separating some of the contamination from the intake air prior to reaching the filter element provides an increase in element service life. The type of pre cleaner recommended for an application typically will depend on the severity of the environment. To maximize element service life choose the pre cleaner design that provides best efficiency within space and weight limits of the application. Reference pre cleaner manufacturers published information for application and installation recommendation guidelines.
Q: Can you judge air filter element service life by visual inspection?
A: Visual inspection is not a recommended method for determining an air filter’s service condition. Measuring intake system restriction is the most reliable determination of filter life. Service by restriction allows the filter to remain in service until the maximum allowable restriction limit for the application is reached. Various restriction indicating devices are available for this purpose.
Reference FMC TSB 89-3R3 for further details.
Q: Can heavy duty air filter elements be cleaned or reused?
A: Most heavy duty air filter manufacturers do not recommend any type of cleaning process be used on their products. Further, they do not warrant their product once it has been cleaned.
Reference FMC TSB 89-4R2 for further details.
Q: Can I replace my Axial Seal element with the new Radial Seal design?
A: Axial Seal and Radial Seal air filter elements are designed to seal differently. “Radial” sealing design elements cannot be fitted into a housing design for axial sealing replacement elements without the use of a conversion kit.
Reference FMC TSB 97-3R1 for further details.
Q: Will more frequent servicing of my air cleaner extend my engines life?
A: Just the opposite, over-servicing will cause increased service cost, time and material and dust contamination of the engine due to:
1. Element damage, due to excessive handling,
2. Improper installation of element,
3. Increased initial inefficiencies.
Reference FMC TSB 89-3R3 for further details.