The 0445120059 common rail injector is widely used in Cummins QSB6.7 engines and is commonly found in Komatsu PC200-8 excavators, wheel loaders, buses, and medium-duty commercial vehicles. This guide explains injector specifications, equipment compatibility, selection methods, common failure symptoms, testing procedures, and a real overhaul case involving a heavy equipment repair shop.
This article focuses on high-quality aftermarket diesel fuel injection solutions designed for construction equipment and commercial applications.
Industry Experience
Our team specializes in diesel fuel injection systems and aftermarket engine parts for construction equipment, trucks, and industrial applications. We provide technical matching support and aftermarket solutions to customers across Africa, the Middle East, Southeast Asia, North America, and South America.
Based on years of experience supplying diesel fuel system components, we frequently assist repair shops, distributors, and fleet operators with injector selection, troubleshooting, and engine overhaul projects.
Quick Navigation
- Product Overview: Aftermarket New vs OEM
- Technical Specifications
- Compatible Engines & Equipment
- Quality Assurance & Testing
- Common Failure Symptoms
- How to Correctly Select the Right Injector Model
- Real Customer Case: Canada – Full Engine Overhaul with 15+ Parts
- FAQ
- Full Technical Guide
1. Product Overview: Aftermarket New vs OEM
1.1 Basic Information
| Parameter | Details |
|---|---|
| OEM reference numbers | Bosch 0445120059 / 0 445 120 059 / Cummins 5263325 |
| Product type | High‑pressure common rail solenoid injector – 100% new aftermarket part (not remanufactured) |
| Primary application | Cummins QSB6.7 engine (Komatsu PC200‑8, trucks, buses) |
| Technology | CRIN2 compatible (solenoid, up to 2500 bar) |
| Nozzle holes | 6 |
| Weight | ~0.8 kg |
1.2 Why Choose Our Aftermarket New Injector
- Price advantage – Significantly lower than OEM dealer pricing.
- New components – All parts brand new (solenoid, needle, nozzle, springs). No reused internals.
- Quality tested – Each unit tested on imported professional common rail test equipment before shipping. Test reports available on request.
1.3 Our Track Record (Real Data)
| Metric | Performance |
|---|---|
| Annual sales volume (0445120059 compatible) | Approximately 1,200 units |
| Customer satisfaction | Positive feedback from majority of repeat customers |
| Warranty | 6 months (unconditional coverage) |
Based on internal records and customer feedback over the past 12 months.
2. Technical Specifications
All values are industry standard for Bosch CRIN2 injectors. Our aftermarket new injectors meet or exceed these specifications.
- Bosch numbers: 0445120059 / 0 445 120 059
- Cummins cross‑reference: 5263262 4945969 397637
- Type: High‑pressure common rail solenoid injector
- Injection pressure (max): 2500 bar
- Nozzle holes: 6
- Static flow @ 100 bar: 210 – 225 ml/1000 strokes
- Return flow @ idle: ≤ 35 ml/min
- Coil resistance (20°C): 0.2 – 0.6 Ω
- Nozzle opening pressure: 255 – 270 bar
- Weight: approx. 0.8 kg
Note on model differences: Bosch 0445120123 and 0445120059 share the same CRIN2 platform, so their basic physical specs are nearly identical. However, they are not interchangeable because of different IQA calibration ranges and application tuning (highway trucks vs. construction equipment). Always use the part number specified for your engine.
3. Compatible Engines & Equipment
3.1 Primary Engine
- Cummins QSB6.7 – 6.7L, 4‑cylinder and 6‑cylinder versions, Tier 3 / Stage IIIA
- Cummins QSB4.5 / QSB5.9 / QSL8.9 Engine
- Komatsu SAA6D107E SAA4D107E Engine
3.2 Known Equipment Fitments (Real Applications)
| Category | Models |
|---|---|
| Excavators | Komatsu PC200‑8 (most common), PC210‑8, PC220‑8 Hyundai R200W7A, R210LC7A, R210LC9, R210NLC7A, R210NLC9, R210W-9, R210W9MH, R250LC7A, R290LC7A, R200W-7A, R210LC-7A, R210LC-9, R210NLC-7A, R210NLC-9, R210W-9MH, R250LC-7A, R290LC-7A |
| Wheel Loaders | Komatsu WA200-6, WA200PZ-6, WA250-6, WA250PZ-6, WA320PZ-6, WA380-6 Hyundai HL730-9, HL730-9S, HL730-9SB, HL730TM-9, HL760-9, HL760-9SB, HL730-7A, HL730TM7A, HL757-7A, HL757-9, HL757-9S, HL757-9SB, HL757TM-9, HL757TM7A, HL760-7A,HL770-7A |
| Buses | Yutong, King Long (QSB6.7 powered) |
Always confirm using your engine serial number or original injector part number.
3.3 Cross‑Reference Numbers
- Bosch: 0445120059 / 0 445 120 059 / 0445120231 / 0 445 120 231
- Cummins: 5263325 / 5263262 (verify – may vary by region)
4. Quality Assurance & Testing
4.1 Testing Process
Every injector we ship undergoes functional testing on imported professional common rail test equipment, including:
- High‑pressure leak test
- Injection quantity at multiple load points
- Return flow measurement
- Solenoid electrical response
Test reports available on request.
4.2 Warranty & Support
- 6 months warranty – covers manufacturing defects. Does not cover damage from contaminated fuel, improper installation, or incorrect application.
- Free technical support – Coding guidance, installation help, and vehicle matching via email/WhatsApp.
5. Common Failure Symptoms (0445120059 in Komatsu PC200‑8)
Based on real workshop feedback, these are the most frequent symptoms when this injector fails:
| Symptom | Likely Cause |
|---|---|
| Black smoke under load | Clogged nozzle (fuel contamination) |
| Engine misfire / rough idle | Incorrect IQA coding or needle wear |
| Hard starting (hot) | Internal leakage – worn valve seat |
| Excessive return flow (≥50 ml/min) | Internal wear |
| Loss of power while digging | Injector not delivering full quantity |
| Injector circuit fault code | Solenoid coil failure (rare in new units) |
Most failures in Komatsu PC200‑8 are fuel‑related – dirty fuel damages nozzles and valve seats.
6. How to Correctly Select the Right Injector Model
Choosing the wrong injector model is one of the most common and costly mistakes in repairs. Even if two injectors look identical, different part numbers have different internal flow characteristics, nozzle hole sizes, and solenoid response curves. Here is a step‑by‑step guide based on real workshop experience.
6.1 Why Can’t You Just Match the Appearance?
Many injectors look almost the same (e.g., 0445120123 vs. 0445120059), but their internal calibration is different. Using the wrong model will cause:
- ECU applying incorrect fuel trim → rough idle, black smoke
- Uneven cylinder work → power loss, higher fuel consumption
- Long‑term risk of pump damage or even piston melting
Real case: A customer bought 0445120123 for their Komatsu PC200‑8 that originally used 0445120059 – just because the parts looked identical. After installation, the machine ran with black smoke and could not dig properly. We guided them to the correct model, and the problem was solved.
6.2 Four Steps to Correct Selection
Step 1: Read the part number from the old injector
Remove one injector and read the laser‑etched number (e.g., 0 445 120 059 or 0445120059). If the number is worn, use a magnifying glass or take a high‑resolution photo and zoom in.
Step 2: Check the engine nameplate or machine serial number
If the old injector is not available, provide the engine model and serial number. For Cummins engines, the ESN (Engine Serial Number) is enough for us to look up the original injector part number.
Step 3: Cross‑reference with ECU IQA codes (if possible)
Using a diagnostic tool, read the IQA codes currently programmed. Each part number range has a corresponding IQA code segment. This can help confirm the correct model.
Step 4: Ask a professional supplier
Send us clear photos of the old injector, the engine nameplate, or the machine model and year. We will reply with a confirmed matching part number – usually within 2 hours. Do not rely solely on online searches or seller claims.
6.3 Common Selection Mistakes
| Mistake | Consequence | Correct Practice |
|---|---|---|
| Buying by appearance only | Wrong model, poor performance | Check the full part number |
| Replacing all injectors with the same number (even if originals were mixed) | ECU alarms, high fuel consumption | Match each cylinder individually |
| Believing “universal replacement” numbers | Flow deviation beyond ECU adjustment range | Use original number or verified alternative |
| Buying from the cheapest seller | High risk of counterfeit or reman units | Choose supplier with test reports and warranty |
6.4 Our Free Selection Support
We provide free injector matching service. Just send us any of the following:
- Clear photo of the old injector (showing the part number)
- Photo of the engine nameplate (model and serial number)
- Machine make, model, and year
We will reply within 2 hours with the correct injector model, along with technical data and common cross‑reference notes.
Even after selecting the correct injector, proper IQA coding is still required after installation. See our Monday article for coding instructions. Selection and coding are two independent steps – both are necessary.
7. Real Customer Case: Canada – Full Engine Overhaul with 15+ Parts
The customer: A heavy equipment repair shop located in Alberta, Canada (customer details omitted for privacy reasons), specializing in Komatsu and Cummins engine repair and overhaul work.
The situation: The shop had a Komatsu PC200‑8 excavator in for a full engine overhaul. The machine had over 12,000 hours and was suffering from low compression, excessive blow‑by, poor fuel economy, and intermittent power loss. The owner decided to rebuild the entire engine rather than patch it up.
The challenge: They needed a complete kit of high‑quality aftermarket parts that would match the original specifications – including injectors, injection pump, pistons, rings, bearings, gaskets, filters, and other consumables – all from a single reliable source to simplify logistics and warranty.
How we helped: The customer sent us the engine serial number, model number, and a list of original part numbers. Our team cross‑referenced everything and prepared a 15+ part solution that included:
- 6 x 0445120059 injectors (matched set with IQA codes)
- 1 x high‑pressure injection pump (remanufactured to OE spec)
- 4 x piston and ring set (6 cylinders)
- 1 x full gasket kit
- 1 x oil filter, fuel filter, and air filter set
- Additional items: connecting rod bearings, main bearings, head bolts, and a water pump
All injectors were 100% new aftermarket units, tested on our imported common rail test bench. We provided test reports for every injector before shipping.
The result: The customer completed the engine overhaul without any parts‑related issues. After installation, they performed IQA coding using our remote guidance. The excavator started on the first crank, idled smoothly, and delivered full digging power with no smoke. The shop owner later told us:
“This was the smoothest overhaul we’ve done. Everything fit perfectly, and your team answered every technical question within hours. We will use you for our next rebuild.”
The customer later returned for additional inquiries involving other machine rebuild projects.
Why this matters: This case shows that we don’t just sell individual injectors – we can supply a complete engine overhaul solution with matched components. Our 6‑month warranty applies to all parts, and our technical support covers the entire installation. This case reflects a typical heavy equipment overhaul scenario based on our aftermarket support experience.
8. FAQ – Common Rail Injector 0445120059
Is Bosch 0445120059 compatible with Komatsu PC200-8?
Yes. Bosch 0445120059 injectors are commonly used in Komatsu PC200-8 excavators equipped with Cummins QSB6.7 engines. Always verify with the engine serial number.
Can Bosch 0445120059 and 0445120123 be used interchangeably?
No. Although both use the CRIN2 platform, internal calibration values and IQA coding ranges are different. Using the wrong injector can cause rough idle, smoke, and reduced engine performance.
Can this injector be used in truck engines?
Yes, if the truck uses a compatible Cummins QSB6.7 engine configuration.
What warranty do you provide?
We provide a 6-month warranty covering manufacturing defects.
How can I avoid counterfeit injectors?
Choose suppliers that provide:
- Injector testing reports
- Warranty coverage
- Technical support
- Product traceability
Extremely low prices may indicate remanufactured or low-quality products.
How do I identify the correct injector model?
You can provide:
- Injector part number
- Engine serial number
- Machine model
- Nameplate photo
Technical matching support can help confirm compatibility before purchase.
Related Models & Internal Links
- Common Rail Injector 0445120123 – Cummins ISBe/ISDe full guide
- Common Rail Injector 0445120007 – Bus & fleet application
- Fuel Injector 0445120231 – Heavy Duty Diesel Applications
- Common Rail Injector 0445120064 – Industrial Diesel Engine Injector Series
9. Summary & Our Commitment
9.1 Key Points
- We supply 100% new aftermarket injectors compatible with Bosch 0445120059 / Cummins 5263325.
- Quality verified on imported professional test equipment.
- 6‑month warranty – honest coverage.
- Trusted by repair shops across North America, Africa, and Asia.
- Real technical support – not just parts. Our Canada engine overhaul case proves what we can deliver.
9.2 When You Buy From Us
You get:
- A product that has been individually tested
- Free injector model matching (send us your old part or engine details)
- Help with complete engine overhaul parts (pistons, pumps, filters, etc.)
- A team that understands diesel injection systems and heavy equipment
9.3 Contact & Inquiries
For pricing, model matching, or technical questions – please contact us directly. We reply within 24 hours.
👉 Inquiry Contact
Looking for Fuel Injector 0445120059 pricing or technical matching support?
Send us your engine model or injector part number, and our team will provide fast compatibility confirmation and quotation support within 24 hours.
Disclaimer
Bosch and Cummins part numbers are used for compatibility and identification purposes only. All products described in this article are aftermarket replacement parts and are not claimed to be original Bosch or Cummins products unless explicitly stated.
Vehicle compatibility may vary depending on engine calibration and regional specifications. Professional verification before installation is recommended.
