Komatsu 12V140 (SA12V140/SDA12V140/SAA12V140E) Fuel Injector 

Engine Compatibility: Komatsu 12V140 Series (SA12V140-1/1C/1D, SDA12V140, SAA12V140E-3); V12-cylinder, 4-stroke, water-cooled, turbocharged/aftercooled heavy-duty diesel; 30.5 L displacement (140×150 mm bore/stroke), rated speed 1800 RPM, Tier 2/Stage II emissions compliant

Genuine Komatsu Part Numbers: 6212-11-3701 (complete injector assembly), 6215-11-3600 (nozzle assembly), 6215-11-3220 (nozzle tip), 6215-11-3620 (nozzle replacement kit)

Core Design: Mechanical inline injector with 7-hole DLL155SN882 nozzle, high-pressure spring-loaded plunger, precision-machined body, and anti-corrosion coating; engineered for peak injection pressure up to 1600 bar and consistent atomization in mining, marine, and power generation duty cycles

Primary Applications: Mining excavators (PC2000-8/PC2500-8), rigid frame dump trucks (HD785-7/HD985-7), heavy bulldozers (D475A-5), industrial power generators (500–800 kW), marine main/auxiliary engines (24/7 continuous operation in extreme dust, high altitude, and corrosive environments)

Product Overview

The Komatsu 12V140 fuel injector is a precision-engineered mechanical fuel delivery component for the 12V140 heavy-duty diesel platform, designed to deliver metered, atomized fuel directly into the combustion chamber at precise timing and pressure. It works in tandem with the Komatsu KP21 inline fuel pump to ensure optimal combustion efficiency, power output, and emissions compliance. Manufactured to ISO 9001 standards with 100% pressure testing, flow calibration, and dimensional inspection, this injector is critical for the 12V140 engine’s 698 kW (936 HP) rated power and 4420 N·m peak torque.

Core Design & Engineering Features

Material & Manufacturing

• High-Strength Alloy Steel Body: Precision-machined from hardened alloy steel with a protective phosphate coating, resistant to wear, corrosion, and high-pressure fatigue.
• 7-Hole DLL155SN882 Nozzle: Hardened steel nozzle with 7 micro-orifices, optimized for fine atomization (droplet size 15–25 μm) and uniform fuel distribution across the combustion chamber.
• Spring-Loaded Plunger Assembly: High-tensile spring with calibrated preload, ensuring consistent opening pressure and precise fuel metering under varying load conditions.
• Precision Machining: Tight tolerances (±0.001 mm) for plunger-to-body clearance, minimizing leakage and ensuring stable injection pressure.
• Anti-Corrosion Treatment: Specialized surface coating on internal components to resist oxidation and wear from ULSD, B5–B20 biodiesel, and high-sulfur fuels.

Injection Performance & Calibration

• Opening Pressure: 140–150 bar (factory-calibrated, ±5 bar tolerance) for consistent fuel delivery at all engine speeds.
• Injection Pressure: Peak pressure up to 1600 bar, optimized for high compression ratio (16.0:1) combustion efficiency.
• Fuel Flow Rate: 180–200 mm³/stroke at rated speed, matched to the 12V140’s 30.5 L displacement and power output.
• Atomization Quality: 7-hole nozzle design ensures complete fuel-air mixing, reducing smoke, NO?, and particulate emissions.
• Timing Accuracy: Synchronized with the KP21 fuel pump for precise injection timing (12–15° BTDC), maximizing power and fuel economy.

Durability & Reliability

• High-Pressure Sealing: Precision-ground sealing surfaces and hardened steel components prevent fuel leakage under extreme pressure and temperature (up to 140°C).
• Wear Resistance: Hardened nozzle tip and plunger surface (HRC 60–62) for extended service life in high-dust mining environments.
• Thermal Stability: Designed to withstand thermal cycling from cold starts (-40°C) to full-load operation (140°C) without distortion or performance degradation.
• Vibration Resistance: Robust body design and secure mounting to the cylinder head, minimizing vibration-induced wear in heavy-duty applications.

Technical Specifications Table

 

Parameter	SA12V140-1 (6212-11-3701)	SAA12V140E-3 (6212-11-3701)	Notes
Injector Type	Mechanical inline, 7-hole nozzle	Mechanical inline, 7-hole nozzle	Standard for all 12V140 variants
Nozzle Model	DLL155SN882	DLL155SN882	Matches 6215-11-3600 nozzle assembly
Opening Pressure	145 bar ±5 bar	145 bar ±5 bar	Factory-calibrated
Peak Injection Pressure	1600 bar	1600 bar	Rated for heavy-duty mining
Fuel Flow Rate	190 mm³/stroke	190 mm³/stroke	At 1800 RPM, full load
Nozzle Orifice Count	7	7	Optimized for atomization
Injector Length	285 mm	285 mm	Standard mounting dimension
Dry Weight	1.8 kg (3.97 lbs)	1.8 kg (3.97 lbs)	Complete assembly
Operating Temperature	-40°C to +140°C	-40°C to +140°C	Wide temperature range

Application-Specific Variants & Cross-Reference

1. SA12V140-1C/1D (Standard Duty): 6212-11-3701; for wheel loaders and mid-size excavators, standard flow rate.
2. SAA12V140E-3 (High-Power): Same part number, calibrated for higher fuel flow to support 698 kW rated power.
3. Marine Variant: Corrosion-resistant coating, marine-grade seals, and modified nozzle for saltwater environments; special order via Komatsu marine dealers.
4. High-Altitude Variant: Calibrated opening pressure for operation up to 4500 m, ensuring consistent performance at reduced air density.
5. Cross-Reference Rule: Always confirm engine serial number (ESN) and CPL (Critical Parts List) before purchasing. Using an incompatible injector will cause poor combustion, power loss, and void Komatsu’s factory warranty.

Installation, Maintenance & Service Guidelines

Installation Best Practices

1. Compatibility Check: Match injector part number to ESN/build code; use only genuine Komatsu injectors, gaskets, and mounting hardware.
2. Nozzle & Injector Body Cleaning: Remove all carbon deposits and debris; inspect for wear or damage (nozzle tip cracks, plunger scoring).
3. Torque Specification: Tighten injector hold-down bolts to 80 N·m in a crisscross pattern; avoid over-tightening to prevent nozzle damage.
4. Fuel System Priming: Bleed air from the fuel lines and injectors; run the engine at idle for 30 minutes to check for leaks and proper operation.
5. Flow Calibration: Verify injector flow rate and opening pressure with a Komatsu injector tester; replace any injector outside factory specifications.

Maintenance Intervals

• Routine Inspection: Check for fuel leaks, smoke, or power loss every 500 operating hours.
• Injector Cleaning: Ultrasonic clean injectors every 2000 hours to remove carbon deposits and maintain atomization quality.
• Nozzle Replacement: Replace nozzle assembly (6215-11-3600) every 4000 hours or if performance degradation is observed.
• Major Overhaul: Replace all injectors and nozzles during engine overhaul (typically 12,000+ hours for mining applications); never mix new and used injectors.
• Fuel Quality: Use only ULSD or approved biodiesel; install high-quality fuel filters to prevent nozzle clogging.

Quality & Warranty

• OEM Manufacturing: Produced at Komatsu’s certified facilities with 100% pressure testing, flow calibration, and dimensional inspection; compliant with ISO 9001 (quality) and ISO 14001 (environmental) standards.
• Warranty: 12 months/1000 operating hours for genuine parts installed by authorized Komatsu dealers; void if non-OEM injectors, improper installation, or poor fuel quality are used.
• Global Support: Available via Komatsu’s worldwide dealer network, with injector testing and calibration services to minimize downtime in remote mining/construction sites.