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SKU:
ZZ3F06075
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Fuel Water Separator Filter FS20121 for Cummins L9 B6.7 V QSB QSL Engine
$66.09
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$66.09
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$66.09
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Compatible Models
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Compatible equipment / model
Fuel Water Separator Filter FS20121 for Cummins
This fuel water separator filter, referencing OEM cross number FS20121, is a replacement filter designed to remove water and debris from diesel fuel for Cummins engines. It protects the fuel injection system by ensuring clean, dry fuel reaches the engine for reliable operation.
Overview
This fuel water separator filter for Cummins engines combines particulate filtration with water separation to protect sensitive fuel injectors from damage. Designed as a direct replacement for part number FS20121, it helps prevent rust, corrosion, and microbial growth in the fuel system. This fuel water separator filter is a critical maintenance component for diesel engines in trucks, generators, and industrial equipment.
Built For Performance
- Advanced water-separating media separates emulsified water from diesel fuel
- High-dirt-holding capacity extends service life and reduces maintenance frequency
- Robust construction withstands fuel pressures and temperature variations
- Precision-engineered filtration media removes abrasive particles down to micron levels
- Built-in drain valve allows for easy water removal during service
Fits These Machines
- for Cummins L9
- for Cummins B6.7
- for Cummins V
- for Cummins QSB
- for Cummins QSL
Specs At A Glance
| Part Number(s) | FS20121 |
| Type | Fuel Water Separator Filter |
| Function | Removes water and contaminants |
| Media | Coalescing filtration media |
Good To Know
Q: Why is a water separator filter important for a Cummins engine? A: Water in diesel fuel can cause injector corrosion, poor combustion, and engine failure. This filter removes water and particles to maintain fuel system integrity and performance.
Q: Can this filter be used in place of the original FS20121 filter? A: Yes, this aftermarket filter is designed as a direct replacement for the FS20121 part number, with matching dimensions and filtration capability. Always confirm thread size and bowl alignment before installation.
Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.