0445120328
BOSCH 0445120328 Common Rail Injector for Cummins ISB / QSB 6.7L Komatsu DAF LF
5263307, 4945969, 5273750, 0986435574 F00RJ01692 DLLA144P1707 1800 bar Product Overview
The Bosch 0445120328 is a heavy-duty commercial common rail diesel injector engineered for Cummins ISB and QSB 6.7L 24-valve engines utilized in DAF LF trucks, Komatsu heavy earthmoving excavators, and industrial machinery. Operating on the Bosch CRIN3 commercial injection system at peak pressures up to 1800 bar, this unit integrates the durable DLLA144P1707 nozzle assembly and F00RJ01692 heavy-duty control valve mechanism. It meets Euro 4, Euro 5, and Tier 4 Interim emission standards. Direct OEM cross-reference replacement for Cummins part numbers 5263308, 5263307, 4945969, and Komatsu 5273750. Proper installation demands strict adherence to lateral connector tube alignment and torque sequence to avoid catastrophic crankcase fuel dilution.
Strict installation sequence required: install and torque injector hold-down clamp (8 N·m + 90°) BEFORE tightening the lateral high-pressure connector tube (45–50 N·m). Tightening the connector tube first causes body binding and severe internal oil dilution.
Compatible Injectors
Vehicle & Engine Fitment
| Vehicle | Engine | Years |
|---|---|---|
| DAF LF 45 / LF 55 Heavy Distribution Truck | PACCAR GR 6.7L (Cummins ISB 6.7) | 2006-2014 |
| Komatsu PC200-8 / PC220-8 Excavator | Komatsu SAA6D107E-1 (Cummins QSB 6.7) | 2007-2016 |
| Cummins ISB 6.7 / QSB 6.7 Industrial & Truck | ISB 6.7L 24V 215-325hp | 2007-2016 |
| Freightliner Custom Chassis Commercial Bus / Truck | Cummins ISB 6.7L | 2008-2015 |
Technical Specifications
| Specification | Value |
|---|---|
| SKU | 0445120328 |
| Brand | Cummins / Komatsu / BOSCH |
| Type | Complete Injector Assembly (Bosch Common Rail (CRIN3 commercial vehicle system)) |
| OE Number | 5263308 |
| Control Valve Core Spec | F00RJ01692 |
| Nozzle Code Core Spec | DLLA144P1707 |
| Injection System | Bosch Common Rail (CRIN3 commercial vehicle system) |
| Operating Pressure Core Spec | 1800 bar |
| Torque Spec | 35 N·m |
| Hold Down Torque | 8 N·m + 90° |
| Warranty | 12 Months |
| Emission Standard | Euro 4 / Euro 5 / Tier 4 Interim |
| Engine Family | Cummins ISB 6.7 / QSB 6.7 / Komatsu SAA6D107E-1 |
| Coding Required | Yes (IMA Code) |
Installation Tips
Tools needed: Flare nut wrench (rail and injector inlet unions), Injector puller / slide hammer kit (if carbon-bonded), Injector seat cleaning brass brush set & industrial vacuum, Seat reaming tool (for restoring carbon-eroded seating faces), Calibrated torque wrench (2 N·m - 50 N·m range), Diagnostic scan tool with IMA/QR coding capability, Digital micrometer / depth gauge for copper washer check
- Isolate Electrical Supply & Vent Rail Pressure: Disconnect main vehicle battery switch; confirm high-pressure rail pressure has dissipated using Cummins INSITE or manual gauge.
- Remove Valve Cover & Rocker Assembly Cover: Remove rocker cover and rocker lever assemblies if necessary to access injector hold-down clamps and lateral fuel passage tubes.
- Extract Lateral High-Pressure Connector Tube: Unscrew the high-pressure connector tube retaining nut from the cylinder head side port; extract the connector tube with an approved removal tool.
- Loosen Injector Hold-Down Clamp Bolts: Back out the hold-down clamp bolts evenly and remove the clamp arm.
- Extract Injector from Cylinder Head Bore: Using an approved Cummins injector puller, lift the injector vertically out of the cylinder head bore without prying against the valve guide.
- Inspect Bore Base & Remove Spent Copper Washer: Ensure the old copper sealing washer has been retrieved; verify bore bottom is clean of carbon buildup.
- Clean Injector Bore & Connector Tube Port: Brush and vacuum the injector seat and the lateral connector tube cross-bore in the cylinder head.
- Install New OEM Copper Seal on Injector: Place a new OEM copper washer on the nozzle shank, using a dab of clean engine oil or assembly grease to retain position.
- Insert Injector Body & Align Connector Port: Position injector in cylinder head with the lateral fuel inlet orifice facing the connector tube opening squarely.
- Install Hold-Down Clamp to First Stage: Snug down the hold-down clamp bolts evenly, then torque to 8 N·m followed by a 90° angle turn.
- Install New High-Pressure Connector Tube (Quill Tube): Insert a brand-new connector tube with fresh O-ring into the cylinder head side port until it seats squarely into the injector body inlet orifice.
- Torque Connector Tube Retaining Nut: Tighten the connector tube retaining nut strictly to 45–50 N·m using a torque wrench. DO NOT overtighten.
- Reconnect High-Pressure Lines & Leak-Off: Reconnect fuel supply lines to 35 N·m; reinstall rocker arms and adjust valve lash to factory clearance.
- ECU Calibration & System Bleed: Program individual injector calibration codes into the Cummins CM2150/CM2250 ECM; crank engine to bleed fuel system.
- CRITICAL CONNECTOR TUBE TORQUE SEQUENCE: Never torque the lateral connector tube before the injector clamp is secured — tightening the connector tube first distorts the injector body and causes catastrophic fuel leak-off into engine oil.
- CONNECTOR TUBE RETORQUE & REPLACEMENT: Always replace the connector tube O-ring and inspect the tube nose for fretting or galling — worn connector tubes leak fuel directly into the crankcase.
- CRANKCASE OIL LEVEL CHECK: If engine oil level rises, immediately stop engine: high-pressure quill tube seal failure pumps diesel directly into the crankcase, causing bearing wipeout.
- STRICT 45-50 N·m CONNECTOR NUT TORQUE: The connector tube nut must be torqued to exactly 45–50 N·m — under-torquing causes external leak; overtightening crushes the injector inlet seat.
Frequently Asked Questions
What causes fuel dilution in engine oil on Cummins ISB 6.7 with 0445120328 injectors?
Fuel dilution on Cummins ISB/QSB 6.7 engines is most commonly caused by improper installation or seal failure of the lateral high-pressure connector tube (quill tube), or a cracked injector nozzle body. Because the injectors and connector tubes are located under the valve cover, any high-pressure fuel leakage drains directly into the engine oil sump rather than outside the engine.
What is the critical installation sequence between the injector clamp and connector tube on 0445120328?
The injector hold-down clamp must be torqued down first (8 N·m + 90°). Only after the injector body is rigidly seated may the lateral connector tube be inserted and torqued to 45–50 N·m. If the connector tube is tightened first, it pushes the injector body laterally, galling the bore and misaligning the internal needle, causing severe internal leakage.
Does Bosch commercial injector 0445120328 require calibration coding?
Yes, 0445120328 requires trim code calibration in the Cummins ECM via Cummins INSITE or compatible commercial scan tool. Programming the code aligns injector fuel delivery characteristics across pilot and main injection pulses for balanced cylinder torque.
Can 0445120328 replace 0445120165?
Both 0445120328 and 0445120165 belong to the Bosch CRIN commercial family. While 0445120165 is calibrated for Yuchai YC6J powerplants, 0445120328 is specifically mapped for Cummins ISB/QSB 6.7L with a dedicated DLLA144P1707 nozzle and connector tube interface. They must not be interchanged across different engine platforms.
What tightening torque is required for the connector tube nut on 0445120328?
The connector tube retaining nut must be torqued to exactly 45–50 N·m (33–37 lb-ft). The high-pressure fuel line union is torqued to 35 N·m.
Cross-Reference & Compatibility
Sister parts, same-platform variants, and known incompatibilities. Entries marked are reference numbers outside this catalogue — the note still applies, but there is no product page for them here.