AMSOIL Marine Dual Remote By-Pass Filtration SystemThe BMK18 is packaged in kit form, which includes the Dual filter mount, mounting hardware, hoses, hose fittings, component parts and installation instructions. In addition, adapter kits of four different sizes enable the BMK18 to be installed on a wide variety of recreational and light commercial marine engines.



Hard-working engines come in all shapes and sizes, from heavy-duty diesels to high performance racing engines. Though seldom recognized as part of this group, marine engines include some of the hardest working, hottest running engines out there.

Marine engines, from those found in recreational watercraft to larger commercial boats, often sit idle in storage for weeks or months and when put on the water are required to run at full throttle for extended periods of time. These torturous conditions place tremendous stress on engines and engine oils. Since clean engine oil is critical for ensuring proper operation and protection, AMSOIL recommends the use of the Marine Dual Remote Filtration System (BMK-18).

The AMSOIL Dual Remote and By-Pass filtration systems have been an integral part of the company’s advanced engine protection product line. Building on the customer-proven success of automotive dual remote and by-pass filtration technology, the Marine Dual Remote Filtration System was created to address the specific severe operating environment of marine engines in both salt and fresh water. For example the hose fittings are coated with a 3 ml layer of Alumiplate™ and 1 ml of zinc and yellow chromate. Standard hydraulic fittings typically survive for 96 hours in the grueling ASTM B-117 Salt Spray Test. When we subjected the Alumiplate™ coated AMSOIL Marine Bypass System fittings to this critical corrosion resistance test protocol, they lasted over 1,000 hours! This means the Alumiplate™ coating on the fittings of the AMSOIL Marine Bypass Filtration System are 10 times more corrosion resistant than standard zinc and yellow chromate plated fittings. While this exclusive Alumiplate™ coating process is expensive, AMSOIL felt this extra margin of system protection was absolutely necessary to provide marine application customers with extraordinary corrosion resistance and protection – and the peace of mind that goes with knowing that the AMSOIL Marine Bypass System is engineered for demanding marine applications. Also, the fasteners and mounting bracket are stainless steel, and the hose are U.S. Coast Guard approved.

Dual Remote Oil Filter Adapter and HosesThe effects of marine engines running predominantly at or near full throttle after extended periods of non-activity include high operating temperatures and increased potential for wear on engine components. The AMSOIL Marine Dual Remote Filtration System offers a clear advantage by providing better oil filtration, increased oil capacity, longer oil and filter life, plus the ability to remove water from the lubrication system. Moisture typically condenses inside engines to combine with residual combustion gases. The resulting compounds strip beneficial additives from engine oil and act as corrosive substances that further degrade the engine oil and promote engine wear. Humid environments make marine engines especially prone to these conditions. The BMK-18 greatly curbs the effects of moisture and condensation by safely retaining water within the filtration system.

Dual remote filtration is a highly efficient filtering process capable of removing the vast majority of wear causing particles which are in the 5-20 micron range. It also has the ability to effectively remove particles down to 1 micron in size. Furthermore, a dual remote filtration system requires a 1.5 to 2 quart oil volume increase, with the added oil offering increased cooling capabilities. The additional hoses, fittings, filters and aluminum mount assemblies also allow the engine oil to dissipate heat more efficiently as it passes through the filtration system, extending the service life of both the engine and the engine oil.

Marine Dual Remote Mercury Installation A large number of marine diesel engines have by-pass oil filtration systems installed by the engine manufacturer. Until now, however, this technology has not been available to smaller pleasure boats and light commercial marine applications.

Depending on the owner’s frequency of use, the improved filtration of the Marine Dual Remote system, along with the use of AMSOIL’s synthetic lubricants, could completely eliminate oil and filter changes during a typical boating season.

With marine engines located in a relatively confined and remote space within the watercraft, ease of filter access and reduced oil spillage are significant benefits of the Marine Dual Remote System.

The BMK-18 is packaged in kit form, which includes the Dual filter mount, mounting hardware, hoses, hose fittings, component parts and installation instructions. In addition, adapter kits of four different sizes enable the BMK-18 to be installed on a wide variety of recreational and light commercial marine engines. The BMK-18 kit offers a new heavy duty, machined aluminum adapter and retaining nut that fits on the existing oil filter mount. Each adapter kit is application specific and must be ordered separately. Please consult BMK-18 Adapter Kit Reference Guide (G-2051) for specific applications. Adapter kits are available for the most popular filter thread sizes. When ordering the BMK-18 request one of the following adapter kits:

  • BK-195 for ¾” x 16 thread
  • BK-196 for 13/16” x 16 thread
  • BK-197 for 18 mm x 1.5 mm thread
  • BK-198 for 20 mm x 1.5 mm thread

Also, for ease of installation in some applications, optional 90 degree fittings (BK-199 and BK-200) can be mounted on the filter adapter collar. These parts are also sold separately.

Installation Instructions

The AMSOIL Marine Dual Remote Filtration System represents the cutting edge of filtration technology-another example of AMSOIL’s commitment to providing quality innovations that can benefit consumers everywhere.


Oil Capacity1 to 2 quart increase
Corrosion resistantYes
External oil filter changesYes
Remove moisture and condensationYes
Ease/convenience of maintenanceYes
Contaminant removalDown to 1 micron