AMSOIL Heavy-Duty By-Pass System

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BMK30 Heavy-Duty By-Pass System
The BMK30 is made from high-quality cast aluminum with a steel filter spud that has been thoroughly tested in on-road and severe off-road service.

* Filter not included with the BMK30 kit.

The EaBP120 Filter and hose (BP250) must be purchased separately.

See Pricing Information or Place an Order
BMK30 Installation and Servicing Instructions
The AMSOIL Heavy-Duty By-Pass Filtration System (BMK30) provides superior filtration performance for heavy-duty on- and off-road applications. The BMK30 is designed specifically for the Heavy-Duty Ea By-Pass Filter (EaBP120), bringing Ea synthetic nanofiber technology to the heavy-duty market.

By-Pass Basics
By-pass oil filtration features a secondary filter with the purpose of eliminating nearly all contaminants in engine oil. By-pass filters have high capacities and eliminate much smaller particles than full-flow filters, including soot. By-pass filters reduce engine wear and increase oil volume, but their high efficiencies mean they also have higher restriction and must be used in conjunction with a full-flow filter.

By-pass filters operate by filtering oil on a “partial-flow” basis. They draw approximately 10 percent of the oil pump’s capacity at any one time and trap the extremely small, wear-causing contaminants that full-flow filters can’t remove. Bypass filters have a high pressure differential, causing the oil to flow through them very slowly and allowing for the removal of smaller contaminants. It is called by-pass filtration because the oil flows from the by-pass filter back to the sump and by-passes the engine. This continual process eventually makes all of the oil analytically clean, reduces long-term wear and can dramatically extend drain intervals.

The BMK30 comes with all necessary hose-end fittings and mounting bolts, but the filter, hose and engine adapter must be purchased separately. The hose and engine adapters are not included due to the kit’s high variability of application, resulting in varied mounting locations, hose lengths and engine adapter sizes. Prior to installing a BMK30 kit, determine where the filter mount will be located and how much hose will be necessary to complete the installation. The installer must also determine the size of the high- and low-pressure ports in order to determine which engine adapters to purchase. Hose is available by the foot from AMSOIL (BP250), and adapter fittings can be purchased from any hydraulics or heavy-duty equipment outlet.

High-Quality, Durable Construction
The BMK30 is made from high-quality cast aluminum with a steel filter spud that has been thoroughly tested in on-road and severe offroad service. The mount is finished with a thick layer of powder-coated paint to provide maximum resistance to the degrading effects of road salt, debris and engine compartment chemicals.

Compatible with Very Large Engines
BMK30 By-Pass Filtration Systems can be plumbed in series or parallel configurations to provide maximum filtration protection for large V12 and V16 engines. The filter mount features a 3⁄8" NPT connector that connects the outlet and inlet of adjacent filter mounts. For more information on engine adapters or the installation of multiple by-pass systems on one application, contact AMSOIL Technical Services at (715) 399-TECH.

General Installation Guidelines
Determine the location of a pressurized oil port on the engine. Pressure ports are usually found on the main oil galley or in close proximity to the full-flow filter head assembly. The oil flow from this source should be plumbed into the inlet side of the filter mount. The outlet will be directed to a low-pressure point on the engine, typically a port located at or near the oil pan. Detailed instructions are included with the BMK30 kit.

The AMSOIL BMK30 By-Pass Filtration System saves money by enabling the installation of an AMSOIL Ea By-Pass Filter. Its heavy-duty design is ideal for equipment subjected to extreme conditions. The ability to mount the BMK30 remotely allows the equipment operator to more easily change filters, adding convenience and reducing the amount of time necessary to perform routine maintenance.

  • Improved Accessibility
    Durable Construction
    Superior Chemical Resistance

The EaBP120 features the same synthetic nanofiber media as the rest of the Ea By-Pass Filter family. The EaBP120 removes 98.7% of all contaminants two microns or larger (ISO 4548-12), and provides superior soot-removal efficiency at less than one micron. It comes complete with a marine powder-coated finish for long filter life, even in extreme conditions.

Increased Oil Capacity
The EaBP120 increases the fluid system capacity by approximately one gallon. The additional oil and extended filtration life provide improved oil cooling and ensure that equipment constantly runs on clean oil. Engine efficiency is increased, providing extended engine life.

Extended Service Life
AMSOIL recommends changing the EaBP120 every other full-flow filter change up to 90,000 miles. Extended oil drain intervals should always be accompanied by an oil analysis program.

Heavy-Duty Filtration
The EaBP120 was designed for heavy-duty applications. Its robust construction and superior filtration performance provide maximum protection over extended drain intervals, reducing downtime, increasing equipment life and saving money.

  • Dramatically Extended Drain Intervals
    Improved Oil Cooling
    Increased Filtration Capacity and Life
    Increased Fluid System Capacity
    Efficient Small Particle and Soot Removal
    Significantly Extended Engine Life
    Equipment Constantly Runs on Clean Oil
    Increased Engine Efficiency
    Remove Particles Less Than One Micron
    Convenient Spin-On Design

The AMSOIL BMK30 and EaBP120 provide maximum filtration performance for virtually all heavy-duty diesel applications, including Class 6, 7 and 8 heavy-duty trucks, off-road equipment, buses, generators, marine engines, logging and agricultural equipment.

OIL ANALYZERS INC., 715-395-0222, is a division of AMSOIL that provides cost-effective, quality oil analysis services.

For more information on AMSOIL Ea Filtration products, including full-flow oil filters, air filters, and by-pass filters and mounts for light-duty equipment, go to or consult the AMSOIL Ea Filtration brochure (G2202), the Ea By-Pass Filter data bulletin (G498) and the Dual Remote Filtration flyer (G1092).