0445120083
BOSCH 0445120083 Common Rail Injector for Yuchai YC4G YC4E YC6J & King Long
G2100-1112100-A38, G21001112100A38F00RJ02806F00RJ034721600 barProduct Overview
The Bosch 0445120083 is a heavy-duty commercial common rail diesel injector belonging to the proven CRIN2-16 platform, specifically engineered for Yuchai Machinery commercial trucks and King Long passenger coaches. Operating at injection pressures up to 1600 bar, this solenoid-driven injector supplies high-precision fuel atomization for Euro 3 compliant YC4G (5.2L 4-cylinder), YC4E (4.3L 4-cylinder), and YC6J (6.5L 6-cylinder) turbocharged intercooled diesel engines. Built with internal hydraulic components including control valve set F00RJ02806, hole-type nozzle F00RJ03472, and magnet assembly F00RJ02703, it delivers reliable multi-injection cycles across severe commercial operating cycles. Original equipment cross-reference is Yuchai OE G2100-1112100-A38, with direct Bosch universal supersession 0445120425 and remanufactured exchange unit 0986AD1036.
HOLD-DOWN CLAMP TORQUE & NOZZLE COPPER WASHER SPECIFICATION: When installing the 0445120083 injector on Yuchai YC4G, YC4E, and YC6J commercial diesel engines, always replace the nozzle copper sealing washer with genuine Bosch F00RJ01453 (7.73 x 14.36 x 1.49 mm). Tighten the injector hold-down clamp bolt in a two-stage progressive sequence to 28-32 N·m. Failure to properly seat the copper washer causes combustion gas blow-by, fuel contamination, and premature control valve erosion resulting in hard starting and DTC P0087.
Vehicle & Engine Fitment
| Vehicle | Engine | Years |
|---|---|---|
| King Long 5.2D Commercial Coach | Yuchai YC6J / YC6JA / YC4G (4.3L - 6.5L Common Rail) | 2006-2016 |
| Yuchai Commercial Medium Truck 4.3D | Yuchai YC6J / YC6JA / YC4G (4.3L - 6.5L Common Rail) | 2006-2016 |
| Yuchai Heavy Commercial Truck 6.5D | Yuchai YC6J / YC6JA / YC4G (4.3L - 6.5L Common Rail) | 2009-2018 |
Technical Specifications
| Specification | Value |
|---|---|
| Fuel System | Bosch Common Rail (CRIN2-16) |
| Peak Pressure | 1600 bar |
| Control ValveCore Spec | |
| Nozzle CodeCore Spec | |
| Magnet Assembly | F00RJ02703 |
| Seal Ring Kit | F00RJ02176 |
| Hold-down Clamp Torque | 28-32 N·m📐 Torque & Angle Wizard → |
| High Pressure Line Torque | 30-35 N·m |
| Coding Standard | Bosch IMA (6/7-Character Alphanumeric) |
| Operating PressureCore Spec |
Installation Tips
Tools needed: Calibrated click-type torque wrench (10-60 N·m range), Brass injector bore cleaning brush set and vacuum extraction adapter, Dedicated commercial diagnostic scanner supporting Bosch IMA injector coding
- Clean the cylinder head injector bore down to bare metal using a brass seat cleaning brush, ensuring all carbon buildup and debris are extracted with a shop vacuum.
- Fit a brand-new copper combustion sealing washer (Bosch F00RJ01453, 1.49 mm thickness) onto the nozzle tip, and install a new viton body O-ring lightly lubricated with clean engine oil.
- Carefully lower the 0445120083 injector assembly straight into the cylinder head bore, aligning the fuel inlet port toward the high-pressure fuel supply manifold.
- Install the injector hold-down clamp and finger-tighten the hold-down bolt to ensure the injector body is perfectly centered and seated flush in the bore.
- Torque the hold-down clamp bolt in two equal steps to the final manufacturer specification of 28-32 N·m to achieve uniform copper gasket crush.
- Thread the high-pressure fuel injection line nut by hand, then torque to 30-35 N·m using an open-end crowfoot socket while supporting the connector fitting.
- Connect the two-pin electrical solenoid connector until the locking clip clicks, and register the individual IMA calibration code into the vehicle ECU using a diagnostic tool.
- Nozzle Gasket Thickness Integrity: Never stack multiple copper washers or reuse flattened gaskets. Installing the wrong washer thickness alters nozzle protrusion into the piston combustion bowl, leading to localized thermal stress, excessive soot generation, and rough idle.
- Fuel Cleanliness Precaution: Before connecting high-pressure fuel lines, crank the engine briefly with fuel lines loose to flush out microscopic contaminants. Particles larger than 2 microns can score control valve F00RJ02806 and cause catastrophic internal backleakage.
- IMA Coding Verification: Following mechanical installation, always program the laser-etched calibration code on top of the injector solenoid into the engine ECU. Uncoded injectors operate on default base maps, causing cylinder-to-cylinder fuel imbalance and elevated exhaust gas temperatures.
Frequently Asked Questions
What symptoms indicate a failing Bosch 0445120083 injector on Yuchai engines?
Typical failure indicators include prolonged engine cranking or refusal to start when hot caused by excessive dynamic return fuel past control valve F00RJ02806, dense black exhaust smoke under acceleration from nozzle F00RJ03472 wear, cylinder misfire codes, and fuel rail pressure loss DTC P0087.
Is ECU IMA coding mandatory when replacing injector 0445120083?
Yes. The Bosch 0445120083 injector features an individual multi-character IMA correction code laser-etched on the solenoid connector head. Entering this code via a commercial diagnostic tool adjusts injection quantity and timing maps for cylinder power balance.
What are the primary OE part numbers for 0445120083?
The primary manufacturer OE reference is Yuchai Machinery G2100-1112100-A38 (also written G21001112100A38). Direct Bosch interchange numbers include universal replacement 0445120425 and remanufactured unit 0986AD1036.
What is the acceptable dynamic backleak rate for bench testing?
Under standard warm operating conditions at full rail pressure (1600 bar), maximum permissible return leakage should not exceed 45 ml/min per injector. Return flow exceeding 50 ml/min indicates internal seat wear in control valve F00RJ02806, requiring overhaul or replacement.
What is the solenoid coil electrical resistance specification?
When tested with a calibrated digital multimeter at 20°C ambient temperature, coil resistance across the two electrical pins must measure between 0.25 and 0.50 Ohms. Measurements outside this range signify internal winding degradation or open circuits.
Diagnostic Trouble Codes & Fault Protocols
Common diagnostic trouble codes (DTCs) triggered when this common rail injector experiences wear, circuit faults, or calibration drift:
Fuel Rail / System Pressure Too Low
Excessive internal backleak from worn control valve seats drops common rail pressure below target under engine load.
Injector Circuit Malfunction / Open Circuit
Solenoid coil resistance drift (0.2-0.5 Ω) or piezo stack degradation triggers driver stage shutdown on affected cylinders.
Cylinder Misfire & Balancing Deviation
Carbon-clogged nozzle spray holes or missing IMA calibration causes uneven cylinder contribution. Recode ECM and verify washer seating.
Fuel Rail / System Pressure Too High
Spill line backpressure or stuck metering valve prevents rail depressurization, creating overpressure risks under load.
Cross-Reference & Compatibility
Sister parts, same-platform variants, and known incompatibilities.
Technical Diagnostic & Service Protocols
Authoritative field procedures, diagnostic testing thresholds, and service SOPs for this assembly.