Cummins QSL9 Marine Diesel — Service & Repower in Ventura, Oxnard, Channel Islands & Santa Barbara

Dependable, quiet, and fuel-efficient power from Cummins’ 8.9L workhorse—installed, maintained, and optimized by
805 Marine Diesel Mechanic.

Request QSL9 Service

Call (805) 774-0637

When your routes run from Ventura Harbor to the Channel Islands, or you’re stacking long days out of
Oxnard and Santa Barbara, you need an engine that blends muscle with refinement. The
Cummins QSL9 marine diesel delivers quiet startups, clean operation, and excellent fuel economy—
and our Cummins-trained technicians keep it that way with factory-correct maintenance, diagnostics,
and repower services.

QSL9 Overview: Why Skippers Choose It

Proven dependability in commercial trawlers, pilot vessels, passenger craft, and long-range cruisers.
HPCR fuel system (high-pressure common rail) for clean combustion, low smoke, and quiet operation.
Excellent fuel economy for range and lower operating cost.
Cummins Captain’s Briefing support + global parts/service network for peace of mind.
Built at Darlington, U.K. and Rocky Mount, NC facilities.

QSL9 Key Specifications

Configuration: In-line 6, 4-stroke diesel
Aspiration: Turbocharged / Aftercooled
Displacement: 8.9 L (542 in³)
Bore × Stroke: 114 × 145 mm (4.49 × 5.71 in)
Rotation: CCW (facing flywheel)
Fuel System: High Pressure Common Rail

Electronics: 12V/24V Quantum System ECM with diagnostics, prognostics & engine protection
Certifications: U.S. EPA Tier 3; designed to meet IACS & SOLAS requirements

Engine Systems & Design Advantages

Engine Design: Robust block, aluminum pistons, metric O-ring seals and edge-molded gaskets to reduce leaks and extend life.
Fuel System: Electronically controlled HPCR maintains high injection pressure across RPM/load for low NVH and quick load acceptance.
Cooling System: Single-loop, low-temp aftercooling (no dual keel coolers) plus tube-and-shell
heat exchanger for durability and easy service.
Air Intake: Rear, water-cooled turbocharger optimized for marine duty.
Exhaust: Cast water-cooled manifold for lower surface temps and safety.
Lubrication: 18 L (19 qt) marine oil pan; engine-mounted or remote filter options.

More Time on the Water, Less in the Yard

Cummins’ latest guidance extends service intervals across the QSB6.7, QSC8.3, QSL9, and QSM11 families. Most items fall on an annual cadence unless hourly limits are reached; some—like cooling system flushes and vibration damper cleaning—extend to ~4 years/2,000 hours. Zinc anodes remain a 6-month/250-hour item.

Want a model-specific plan? See our Cooling System Maintenance guide or ask us to tailor a schedule for your hours, duty cycle, and water conditions.

Built for Commercial & Recreational Duty

The QSL9’s blend of low-RPM torque, quiet operation, and electronic protections makes it a favorite for
commercial trawlers, pilot boats, ferries and for recreational yachts and sportfishers running the Santa Barbara Channel.

Smart Diagnostics for Confident Passages

Quantum System electronics provide live insight into fuel burn, duty cycle, load, and speed—helping captains optimize range and spot issues early. Pair this data with 805 Marine Diesel Mechanic’s Cummins tooling and you get fast, accurate troubleshooting.

QSL9 Services by 805 Marine Diesel Mechanic

Preventative Maintenance: oil & filters, zincs, belts, cooling & exhaust checks, valve sets.
Diagnostics & Repairs: HPCR/injectors, turbo, cooling system, electrical & sensor faults.
Repower & Upgrades: Clean-sheet installs or repowers with QSL9; integration with controls, harnesses, mounts & exhaust.
Mobile Dockside Service: Ventura Harbor, Channel Islands Harbor, Santa Barbara Harbor & Oxnard marinas.

View Cummins PM Schedule