Description
Product Overview
The 2-Pack FS1098 Fuel Water Separator for Cummins B6.7 / ISL8.9 delivers professional-grade fuel filtration for diesel engines. Manufactured with advanced synthetic media for superior contaminant capture and water separation, this filter protects your high-pressure common rail injection system from the microscopic particles and moisture that cause premature injector and pump failure.
As diesel injection pressures climb past 30,000 PSI in modern engines, fuel cleanliness has never been more critical. A single tank of contaminated fuel can cause thousands in injector damage. This filter provides the first and most important line of defense for your fuel system.
Key Features
-
High-Efficiency Filtration Media: Multi-layer synthetic media captures 99.9% of particles at the rated micron level, exceeding standard cellulose elements in both efficiency and dirt-holding capacity.
-
Advanced Water Separation: Coalescing technology removes emulsified and free water from diesel fuel, preventing injector tip erosion and microbial growth.
-
OEM-Spec Construction: Manufactured to ISO 9001 quality standards with precision-threaded base plate, anti-drain back valve, and high-burst-strength canister.
-
Direct Fit Replacement: Engineered as a drop-in replacement — no modifications, adapters, or special tools required.
-
Extended Service Life: Higher dirt-holding capacity means longer intervals between changes, reducing downtime and per-mile filtration costs.
Compatibility
| Specification |
Detail |
| Engine |
Cummins B6.7, ISL8.9, L9 Diesel |
| Application |
Commercial Trucks, RVs, Buses |
| Replaces Part # |
FS1098, 5319680, 5308722 |
| Micron Rating |
2-10 Micron Absolute |
| Filter Type |
Spin-On with Water Separation |
Why Upgrade Your Fuel Filtration?
-
Extended Injector Life: Injectors operating at 30,000+ PSI have micron-level clearances. Better filtration means injectors lasting 200K+ miles instead of failing at 100K.
-
Improved Cold-Weather Reliability: Superior water separation prevents ice crystal formation in fuel lines during winter.
-
Reduced Maintenance Costs: Preventing one HPFP failure saves $5,000-$10,000 — the cost of a lifetime of premium filters.
-
Better Fuel Economy: Clean injectors atomize fuel more efficiently, maintaining optimal combustion over the vehicle lifetime.
Installation Guide
-
Safety First: Park on level ground, engage parking brake, allow engine to cool. Have a drain pan ready.
-
Relieve Fuel Pressure: Remove fuel cap. On some models, pull fuel pump fuse and crank briefly.
-
Remove Old Filter: Use oil filter wrench to loosen. Unscrew by hand and lower into drain pan.
-
Prep New Filter: Apply thin film of clean diesel to gasket. Pre-fill if housing design allows.
-
Install: Spin on by hand until gasket contacts. Tighten 3/4 to 1 full turn. DO NOT over-tighten with wrench.
-
Prime System: Cycle key ON (not START) 5-6 times for 30 seconds each to purge air. Check for leaks.
-
Start & Verify: Start engine, check for leaks at idle, let run 2 minutes, recheck. Dispose of old filter properly.
Frequently Asked Questions
Q: What engines does this fit?
A: Fits Cummins B6.7, ISL8.9, and L9 diesel engines in Freightliner M2, International MV, Blue Bird Vision buses, motorhomes, and commercial vehicles from 2010-present. Replaces OEM part numbers 5319680 and 5308722.
Q: How is this different from the fuel filter?
A: FS1098 is a fuel water separator — it removes water, sediment, and larger particles BEFORE fuel enters the main filter. This 2-stage filtration protects the high-pressure common rail system. Replace both filters together.
Q: What micron rating?
A: 10-micron nominal filtration with 98% water separation efficiency. Integrated PCV (pressure control valve) maintains consistent fuel pressure. Exceeds OEM water removal performance.
Q: How often should I drain the water separator?
A: Drain the water bowl weekly during regular operation or when the WIF (Water-In-Fuel) warning light illuminates. For sitting vehicles, drain monthly. Water accumulation is higher in humid climates and with biodiesel blends above B5.
Q: Can I use this on my RV Cummins generator?
A: Yes. If your RV has a Cummins Onan generator with B6.7 or ISL engine platform, this is a direct fit. Verify generator model number — common on class A diesel pushers with Onan QD series.
Related Products
Related Guides & Articles
