The Caterpillar 320-0680 fuel injector is a Cat fuel injector group used in selected C4.4 and C6.6 diesel engine applications. Cat’s official parts catalog lists the 320-0680 for a range of equipment, including wheeled excavators, backhoe loaders, telehandlers, asphalt pavers, compactors, generator sets, industrial engines, and other specialized machines. Cat also lists 10R-7672 as a Cat Reman common rail fuel injector associated with this application.
The Cat parts catalog gives the 320-0680 a length of 8.8 inches and a height of 4.8 inches. Exact fitment should be confirmed using the engine serial number, equipment configuration, and original injector part number before ordering.
1. What Is the Caterpillar 320-0680 Fuel Injector?
The 320-0680 is a diesel fuel injector designed to deliver a controlled quantity of fuel into the engine cylinder at the required time.
As a precision fuel-system component, injector performance directly affects:
- Fuel delivery
- Combustion quality
- Engine power
- Starting performance
- Fuel economy
- Exhaust emissions
Cat identifies the 320-0680 as an Injector Gp-Fuel and lists it for selected C4.4 and C6.6 applications. The same Cat parts page also shows 10R-7672 Cat Reman Common Rail Fuel Injector as an associated alternative.
2. Caterpillar 320-0680 Fuel Injector Specifications
The publicly available Cat specifications for the part are relatively limited, so it is better to use verified dimensional and identification information rather than publish unconfirmed internal injector calibration data.
| Specification | Details |
|---|---|
| Part Number | 320-0680 |
| Product Type | Fuel Injector / Injector Group-Fuel |
| Main Engine Applications | Caterpillar C4.4 and C6.6 |
| Length | 8.8 in (223.5 mm) |
| Height | 4.8 in (121.9 mm) |
| Cat Reman Reference | 10R-7672 |
| Related Component | 517-8243 Injector Sleeve |
Cat’s catalog also lists 299-8229 High Efficiency Fuel Filter among parts frequently purchased with the 320-0680 and 517-8243 Injector Sleeve as a related component.
Detailed values such as nozzle-hole dimensions, spray angle, coil resistance, and injector calibration should not be assumed from generic aftermarket specifications because the correct configuration depends on the specific engine and fuel system.
3. What Engines and Equipment Use 320-0680 Fuel Injector?
The 320-0680 is officially listed for selected Caterpillar C4.4 and C6.6 applications. Cat’s compatibility catalog includes the following equipment groups.
Wheeled Excavators
- M313D
- M315D
- M315D2
- M316D
- M317D2
- M318D
- M318D MH
- M322D
- M322D MH
Backhoe Loaders
- 430E
- 450E
Telehandlers
- TH337C
- TH407C
- TL943C
Asphalt Pavers
- AP-500E
- AP-555E
- BG500E
- BG555E
Compactors
Selected applications include:
- CB-44B
- CB-54
- CB-54B
- CB-64
- CP-54
- CP-54B
- CS-54
- CS-54B
- CS-64B
- CW-34
Other Applications
Cat also lists the 320-0680 for selected:
- C4.4 generator sets
- LC30XX generator applications
- C4.4 and C6.6 industrial engines
- R1300G II Load Haul Dump equipment
- SPF343C pumper applications
Because Cat equipment can have different engine arrangements and configurations, the machine model alone should not be treated as a final fitment confirmation. Cat specifically advises checking the equipment’s current configuration before purchase.
4. What Are the Common Symptoms of a Failing 320-0680 Fuel Injector?
A worn or malfunctioning injector can affect combustion and engine performance. Common symptoms include:
Hard Starting
An injector with poor fuel delivery or internal leakage can contribute to extended cranking or difficult starting.
However, fuel pressure, fuel supply, air in the fuel system, and other engine problems should also be checked.
Rough Idle or Misfire
Uneven injector performance can cause unstable combustion in one cylinder.
Possible symptoms include:
- Rough idle
- Engine vibration
- Uneven running
- Cylinder misfire
Loss of Engine Power
Poor injector performance can reduce combustion efficiency and engine output, particularly under load.
Before replacing the injector, check other possible causes such as fuel restrictions, air intake problems, turbocharger issues, and engine control faults.
Excessive Smoke
Poor fuel atomization or incorrect fuel delivery may contribute to black, white, or gray smoke.
Smoke color alone, however, is not sufficient to identify an injector problem.
Increased Fuel Consumption
An injector that is not delivering fuel correctly can reduce combustion efficiency and increase fuel consumption.
Injector testing should be used to determine whether the injector is actually responsible.
Fuel System or Injector-Related Fault Codes
Electronic engine systems may record diagnostic faults when abnormal fuel-system or injector performance is detected.
Diagnostic testing should be completed before replacing expensive fuel-system components.
5. How Do You Know When to Replace a 320-0680 Fuel Injector?
There is no universal mileage interval that can accurately determine when every 320-0680 injector needs replacement.
Service life depends on:
- Fuel quality
- Filtration
- Water or fuel contamination
- Engine operating conditions
- Maintenance history
- Operating hours
Replacement is generally appropriate when testing confirms that the injector is outside the required performance range or when injector-related faults remain after other possible causes have been eliminated.
A proper diagnostic process should normally include checking:
- Fuel supply and filtration
- Engine diagnostic codes
- Cylinder performance
- Injector operation
- Fuel system pressure
- Related wiring and control components
This approach helps prevent unnecessary injector replacement.
6. What Should Be Checked During Injector Replacement?
Replacing the injector is only part of the repair.
Injector Sleeve and Sealing Components
The 517-8243 injector sleeve is listed by Cat as a related component for the 320-0680. Inspect the sleeve and applicable sealing components during injector replacement.
Fuel Filter
Fuel contamination can damage precision injection components. The fuel filter should be inspected and replaced according to the applicable engine maintenance procedure.
Fuel Connections
Inspect fuel connections for contamination, leakage, or damage before installing the replacement injector.
Installation Procedure
Always use the installation sequence and torque specifications for the exact engine configuration. Avoid applying specifications from another Caterpillar engine simply because the injector part number is similar.
7. 320-0680 Fuel Injector and 10R-7672: Are They the Same?
320-0680 and 10R-7672 are closely associated in Caterpillar’s parts catalog.
Cat identifies:
- 320-0680 — Injector Gp-Fuel
- 10R-7672 — Cat Reman Common Rail Fuel Injector
The Cat parts catalog displays 10R-7672 as an associated alternative for the 320-0680.
The product type should therefore be confirmed before purchasing, especially when comparing a new injector with a Cat Reman or aftermarket replacement.
8. What Are the Common Cross-Reference Numbers for 320-0680 Fuel Injector?
Aftermarket diesel parts listings commonly associate the 320-0680 with numbers such as:
- 10R-7672
- 306-9380
- 2645A747
- 2645A734
- 2645A718
These references appear in aftermarket injector listings, but they should not automatically be treated as universal direct replacements.
For the most accurate identification, compare the original injector number and engine information before ordering.
9. Related Caterpillar Fuel Injector Models and Guides
For more information about other Caterpillar fuel injector models, refer to the related guides below for details on Caterpillar injector identification, engine and equipment applications, compatibility, technical specifications, performance, and replacement selection.
- Fuel Injector 326-4700 For Caterpillar C6 C6.4 Engine CAT320D Excavator
- Fuel Injector 326-4756 for Caterpillar C6 C6.4 Engine 312D
- Fuel Injector 320-0655 for Caterpillar C6.6 Perkins 1106D-E66TA
- Fuel Injector 320-0677 For Caterpillar C6.6 Engine 320D 323D Excavator
Read more:
- Fuel Injector 236-0962
- Fuel Injector 127-8218
- Fuel Injector 320-0690
10. Frequently Asked Questions About 320-0680 Fuel Injector
1. What engine does the 320-0680 injector fit?
The 320-0680 is listed for selected Caterpillar C4.4 and C6.6 engine applications. Exact compatibility depends on the equipment and engine configuration.
2. What is the replacement number for 320-0680 Fuel Injector?
10R-7672 is the Cat Reman common rail fuel injector associated with the 320-0680 in Cat’s parts catalog. Aftermarket listings may also show additional cross-reference numbers, so fitment should be verified before ordering.
3. Can a bad 320-0680 cause black smoke?
Yes. Poor injector performance can contribute to incomplete combustion and black smoke. However, restricted air intake, turbocharger problems, fuel-system faults, and other engine issues can cause similar symptoms.
4. Should all injectors be replaced together?
Not necessarily. If testing identifies one failed injector and the remaining injectors are performing correctly, replacing the affected unit may be sufficient. If several injectors show abnormal performance, replacing multiple units may be more practical.
5. How can I confirm whether 320-0680 fits my machine?
The safest method is to compare the original injector number, engine serial number, arrangement information, and equipment configuration. Cat also recommends confirming compatibility because changes to the manufacturer’s configuration can affect fitment.
6. Is 2645A747 the same as 320-0680?
2645A747 is commonly cross-referenced with 320-0680 in aftermarket listings, but it should not be assumed to fit every application without verification.
7. What related parts should be checked when replacing the injector?
The injector sleeve, sealing components, fuel filter, and fuel connections should be inspected as part of the replacement procedure. Cat lists 517-8243 Injector Sleeve and 299-8229 High Efficiency Fuel Filter alongside the 320-0680 in its parts catalog.
Conclusion
The Caterpillar 320-0680 fuel injector is a fuel-system component used in selected C4.4 and C6.6 applications across a broad range of Cat construction, industrial, paving, compaction, generator, and material-handling equipment.
Its Cat parts references include 10R-7672, while aftermarket listings may also associate the injector with numbers such as 2645A747 and 306-9380. Because Caterpillar equipment can have different configurations, part-number and engine-information verification is essential before ordering.
For reliable replacement, confirm the original injector number, inspect related fuel-system components, and follow the service procedure specified for the exact engine configuration.
Disclaimer
All brand names, trademarks, OEM part numbers, engine models, equipment models, and vehicle names mentioned in this article are used for reference and compatibility identification purposes only. Unless expressly stated otherwise, Pioneer Diesel Parts supplies high-quality aftermarket replacement parts featured on this website. These products are not genuine OEM products, and the respective original equipment manufacturers do not manufacture, affiliate with, endorse, or sponsor them. All trademarks and registered trademarks are the property of their respective owners.