Overview: FS1280 Heavy-Duty Spin-On Fuel Water Separator
The Landown LD-FS1280 Fuel Water Separator Filter (Fleetguard FS1280 direct replacement) is a high-performance spin-on primary diesel fuel filtration cartridge engineered specifically for Cummins 3.9L (4B/4BT/4BTA), 5.9L (6B/6BT/6BTA), and 8.3L (6C/6CT/6CTA) diesel engines. Ideal for heavy stationary diesel power generator sets, commercial transport trucks, agricultural tractors, and construction excavation machinery, the FS1280 utilizes a heavy-duty resin-impregnated barrier media that achieves 90% free and emulsified water separation and 96% particle filtration efficiency at 20 microns (SAE J1985), effectively protecting high-pressure fuel injection systems from rust, water-induced cavitation, and abrasive particle wear.
Key Performance & Construction Features
- Dual-Action Water Coalescing & Particle Filtration: Micro-pleated hydrophobic cellulose media repels emulsified moisture and free water droplets into the collection base while capturing abrasive dirt and rust down to 20 microns.
- Integrated Self-Venting Drain Valve: Heavy-duty twist drain valve allows rapid, tool-free drainage of collected water and heavy sediment without introducing air into the fuel line.
- Heavy-Gauge Steel Canister & 13/16-18 Baseplate: Drawn high-tensile steel shell and precision-machined 13/16-18 UNS-2B threaded mounting plate withstand cyclical fuel pressure pulses and intense engine vibration.
- Hydrocarbon-Resistant Buna-N Nitrile Gasket: Premium synthetic rubber sealing ring maintains elasticity and prevents external fuel leakage across severe operating temperatures from -40°C to +120°C.
Technical Specifications
| Specification / Parameter | Verified Technical Detail |
|---|---|
| Product Model / SKU | LD-FS1280 / FS1280 |
| Primary OEM Part Numbers | Cummins 3930942, 3903410, 3890706, 3315843 |
| Filter Type | Spin-On Fuel Filter / Water Separator with Drain |
| Thread Size | 13/16-18 UNS-2B (13/16″-18) |
| Overall Height | 164.85 mm (6.49 in) |
| Largest Outer Diameter (OD) | 93.73 mm (3.69 in) |
| Seam Outer Diameter | 93.47 mm (3.68 in) |
| Gasket Outside Diameter (OD) | 71.88 mm (2.83 in) |
| Gasket Inside Diameter (ID) | 62.48 mm (2.46 in) |
| Water Separation Efficiency | 90% Free Water / 90% Emulsified Water Separation |
| Filtration Efficiency (TWA) | 96% @ 20 Micron (SAE J1985 Standard) |
| Operating Temperature Range | -40°C to +120°C (-40°F to +248°F) |
| Operating Fuel Compatibility | Ultra-Low Sulfur Diesel (ULSD), Agricultural Distillate Diesel, Biodiesel Blends (B20) |
OEM Interchange & Cross-Reference Table
| Brand / Manufacturer | Cross Reference / Equivalent Part Number |
|---|---|
| Fleetguard (OEM) | FS1280, FS1275, FF5038, FF5285 |
| Cummins | 3930942, 3903410, 3890706, 3315843 |
| Donaldson | P551329, P558000 |
| Baldwin | BF1280 |
| Wix | 33357, 33585, 33585MP |
| Komatsu | 6732-71-6120, 6732716120 |
| Case IH | J903410, J930942 |
| Volvo | 36846 |
| Luber-finer / Fram | Luber-finer LFF8000 | Fram PS8047 |
Engine & Generator Equipment Application Guide
The FS1280 fuel water separator is widely installed across Cummins-powered industrial equipment, prime generator sets, commercial trucks, and agricultural machinery:
- Cummins Diesel Engines:
- 3.9L 4-Cylinder: 4B3.9, 4BT3.9, 4BTA3.9, B4.5
- 5.9L 6-Cylinder: 6B5.9, 6BT5.9, 6BTA5.9, B5.9, ISB 5.9L
- 8.3L 6-Cylinder: 6C8.3, 6CT8.3, 6CTA8.3, C8.3, ISC 8.3L, QSC 8.3L
- Stationary & Mobile Diesel Generator Sets: Prime and standby power generation units (30 kW – 250 kW) in commercial buildings, telecommunication towers, mining camps, and construction sites.
- Commercial On-Highway Trucks: Freightliner FL-Series, International, Ford Medium-Duty Trucks with Cummins B-Series engines.
- Agricultural & Construction Machinery: Case IH Maxxum Tractors, Komatsu Excavators & Wheel Loaders, Hyundai Construction Equipment.
B2B Wholesale, OEM & Custom Manufacturing Capabilities
As a professional manufacturer and global exporter of heavy-duty diesel filtration systems, Landown Filter supplies wholesale distributors, aftermarket private brands, and fleet contractors with:
- Custom Laser & Silk-Screen Branding (OEM/ODM): Customized private label printing, custom part numbers, barcoding, and brand logo silk-screening on filter canisters.
- Heavy-Duty Export Packaging: 12-pack or 24-pack master cartons, custom printed retail individual boxes, moisture-barrier wrapping, and palletized ocean freight loading.
- Strict Quality & Leak Testing: 100% burst pressure, water separation efficiency, and leak tested in compliance with SAE J1985 / ISO 19438 standards.
- Direct Factory Wholesale Pricing: Low sample MOQ for initial quality testing, stable high-volume capacity, and rapid global fulfillment.
Frequently Asked Questions (FAQ)
Q1: Is the Landown FS1280 fuel water separator a direct replacement for Fleetguard FS1280 and Cummins 3930942?
A: Yes, 100%. The Landown FS1280 is manufactured to identical OEM dimensional and filtration standards. It features exact 13/16-18 UNS-2B threads, 164.85 mm overall height, 93.73 mm outer diameter, and integrated drain valve for plug-and-play installation without adapters.
Q2: How does the FS1280 separate water from diesel fuel?
A: The FS1280 utilizes treated hydrophobic barrier media. Free and emulsified water droplets in the diesel fuel are coalesced on the media surface, form heavier drops, and settle to the bottom sediment bowl, achieving 90% water separation efficiency.
Q3: What are the recommended service replacement intervals for FS1280 on generator sets?
A: For stationary standby generator sets, annual filter replacement (or every 250 operating hours) is recommended. Monthly manual draining of collected water via the bottom twist valve ensures maximum injector protection.
Q4: What is the packaging specification and MOQ for OEM / wholesale orders?
A: Standard packaging is packed 12 or 24 units per master shipping carton. We support flexible trial order quantities for new distributors, as well as full container shipments with custom brand packaging.