AVi168C3003 Cummins Alternator 28V 150A
Applicable models:For Cummins 4S bus generator applications
Reference part number:AVi168C, AVi168C3003, AVi168C3001, 5289631, 5344074, C5289631.
| Rated output : | 28V 150A |
| Pulley : | 8PK |
| Size : | 31*29*24CM single unit inner box |
| Weight : | net weight：11.65KG gross weight：12.25KG |
| Packaging : | Neutral kraft paper packaging |
| Spot/Pre sale : | Spot goods |
| Warranty : | 1 year |
| Product number : |
| Type : | ACgenerator Alternator |
| Specification : | 28V 150A |
| Pulley : | 8PK |
| Brand : | NUOJIN |
| Number : | AVi168C AVi168C3001 |
| Quality : | new |
| Delivery time : | 10DAY |
Product Overview
The AVi168C3003-series alternator (OE AVi168C3003, AVi168C3001, C5289631) is a new, OE-spec replacement charging unit built for Cummins 4S bus generator applications. Rated at 28V 150A with an 8PK pulley, this heavy-duty alternator restores stable battery charging and dependable electrical-system operation so your bus keeps running reliably.
This aftermarket unit matches the original charging-system requirements of the Cummins bus application family. It delivers consistent high output across the load range, keeping the battery charged and the electrical system stable. The unit is stocked in-house, backed by a 1-year warranty with a 10-day dispatch lead time. Reliable charging output design guarantees dependable electrical-system performance for your 28V bus.
Key physical specs: net weight 11.65 kg, gross weight 12.25 kg, overall dimensions 31 x 29 x 24 cm, supplied in a neutral kraft inner carton.
Cummins 4S Bus Charging System
Cummins-powered 4S buses rely on a correct 28V alternator match so the battery is properly charged and all electrical loads run reliably. The 8PK pulley is engineered to match the serpentine belt drive system for dependable operation after installation.
Technical Specifications
| Parameter | Specification |
|---|---|
| OE numbers | AVi168C, AVi168C3003, AVi168C3001, 5289631, 5344074, C5289631 |
| Voltage | 28V |
| Rated output | 150A |
| Pulley | 8PK |
| Application | Cummins 4S bus applications |
| Quality | New |
| Warranty | 1 year |
| Net weight | 11.65 kg |
| Gross weight | 12.25 kg |
| Dimensions | 31 x 29 x 24 cm |
| Packaging | Neutral kraft box |
| Lead time | 10 days, in stock |
Engine Compatibility and Cross Reference
This alternator fits Cummins 4S bus generator applications. Do not rely solely on the application for fitment validation; always verify the engine model, pulley groove count, mounting brackets, wiring connector and output rating stamped on your original alternator.
| Equipment | Application | Typical Applications |
|---|---|---|
| Cummins engine | Bus | 4S bus applications |
| Commercial use | Bus / generator | Related Cummins bus and generator applications |
| Fleet use | Commercial | Related heavy-duty applications |
Multiple OE numbers exist across different production batches for this same alternator family. If your original alternator carries any one of the listed part numbers, the AVi168C3003-series unit is a direct drop-in replacement.
What to Look for in a Replacement
Follow these five verification steps before placing your order to avoid wrong-part returns:
1. Check the nameplate data on your old alternator: confirm the output is 28V 150A. A different voltage or output rating is not interchangeable.
2. Confirm the pulley is 8PK. A mismatched groove count will slip the belt and cause under-charging.
3. Confirm your application is a Cummins 4S bus. Other applications use different alternator assemblies.
4. Match the OE / reference part numbers stamped on your original alternator housing.
5. Weight cross-check: a genuine matching unit weighs about 11.65 kg net; a significant weight difference indicates the wrong assembly or low-grade build quality.
Application Scenarios
Independent repair shops and auto-electric workshops servicing Cummins-powered buses across the Americas, the Middle East, Africa, Asia and Europe.
Parts counters and jobbers stocking commercial-vehicle charging and starting electrical components.
Bus fleet operators and transit authorities maintaining Cummins 4S bus fleets.
Used vehicle export traders supplying second-hand buses to global secondary markets.
Maintenance teams restoring vehicles to factory-standard condition.
Installation Steps and Precautions
Installation must comply with the assembly specifications for low-voltage electrical equipment and the general requirements for engine charging systems. The following are standardized installation steps, including compatibility inspection and practical operation precautions, to ensure stable operation after installation.
Pre-Installation Preparation
Power cut protection: Turn off the engine ignition switch and disconnect the negative battery cable to avoid short circuits caused by accidental circuit contact during installation.
Tool preparation: Prepare a torque wrench, socket set, screwdriver, belt tension gauge, wire harness clips, conductive paste, metal cleaner and rags. Have small accessories such as gaskets of the same specification ready.
Component and Compatibility Inspection
Confirm the new alternator is the 28V 150A model with an 8PK pulley and compatible with the engine of the target vehicle.
Check that the alternator housing has no cracks, the pulley rotates freely without wobble, the cooling fan is intact, and the terminal studs are in good condition.
When replacing an old alternator, clean the oil stains and rust at the old installation position. Inspect the serpentine belt for wear or cracking and replace it if necessary before installing the alternator.
Cleaning the Installation Workstation
The alternator is usually installed on the engine front bracket. For some vehicles, first remove the surrounding air filter box, small pipeline brackets or wire harness shields, clear obstructing wire harnesses, and reserve sufficient operating space to prevent component interference during installation.
Securing the Main Body of the Alternator
Firmly fit the alternator onto the engine mounting bracket. Align the pulley with the serpentine belt path to ensure correct belt alignment without misalignment or slipping, so as to ensure reliable drive during subsequent operation.
Pre-tighten 2-3 matching fixing bolts diagonally, then tighten them to the standard torque with a torque wrench (fine-tune with reference to the corresponding Cummins maintenance manual). Insufficient torque leads to violent vibration during operation, while excessive torque may damage the housing or the bracket threads.
Connecting the Electrical Circuits
Output terminal (B+): Locate the alternator main output terminal and connect the charging wire from the battery. Before connection, wipe the terminal with a cleaner to remove the oxide layer; if necessary, apply a small amount of conductive paste to reduce contact resistance. Tighten the terminal nut to 8+/-2 Nm to prevent the terminal from overheating and ablation when a large current passes through the charging circuit.
Excitation / sense terminal (D+ or IG): Connect the excitation or ignition-sense wire to the alternator excitation terminal. Do not insert or pull the connector forcefully to avoid bending and damaging the pins. When arranging the wire harness, keep it away from rotating components such as the engine pulley and fan. Fix the harness with clips to prevent wear and leakage during operation.
Finalization and Functional Testing
Reinstall the previously removed components such as the air filter box and pipeline brackets in sequence, and confirm all shields and clips are properly installed. Reconnect the negative battery cable, tighten the terminal nut, and check for no looseness.
Start the engine and verify the charging output: with the engine running, the charging voltage should read between 27V and 29V across the battery terminals for a 28V system. Confirm the charge indicator lamp goes out and no abnormal noise comes from the alternator.
If the charge lamp stays on or charging voltage is too low, check belt tension, alternator drive and wiring connections. If output voltage is too high, the voltage regulator may be at fault.
FAQ
Q: Does this alternator fit all Cummins 4S bus applications?
A: This AVi168C3003-series alternator is built for Cummins 4S bus generator applications. Always confirm your application and old-alternator OE number before ordering.
Q: My old alternator shows OE number AVi168C3001 or C5289631 or 5289631. Will AVi168C3003 work?
A: Yes. These OE numbers belong to the same alternator family, differing only by production revision and market specification, so the AVi168C3003-series unit serves as a direct replacement.
Q: Is this a new or remanufactured alternator?
A: This unit is a new alternator, quality-tested to original specifications and backed by a 1-year warranty.
Q: What is the normal charging voltage for a 28V system?
A: With the engine running, charging voltage should read between 27V and 29V across the battery terminals. Too-low voltage indicates an under-charging problem; too-high voltage suggests a regulator fault.
Q: What is your warranty and lead time?
A: Goods are in stock with a 10-day dispatch lead time. A 1-year warranty applies from installation date; it excludes damage caused by mis-installation, poor cable connections, reversed polarity or vehicle electrical-system faults.
In Practice
For technicians working on Cummins bus platforms: before removing the existing alternator, perform charging-system diagnostics. Measure battery voltage with the engine off and running. Defective batteries, corroded cables, bad ground points or a slipping belt can mimic alternator-failure symptoms, so do not replace the alternator blindly. Always disconnect the battery negative terminal before commencing removal work.
Take photos of wiring terminals and bolt positions during disassembly to avoid mis-wiring during reassembly. Inspect the serpentine belt and tensioner before fitting the new alternator, because a worn belt or weak tensioner will quickly reduce charging output. Tighten mounting bolts to the Cummins official workshop-manual torque specifications.
References
The installation method and related precautions are standardized content summarized and integrated based on the universal assembly specifications of Cummins engine charging systems, industry installation standards for low-voltage alternators of the same specification, and practical experience in the bus-repair field. Equipment applications are compiled from original-equipment fitment data for the AVi168C3003-series alternator family covering Cummins 4S bus applications.
About the Author
This article was written by the senior auto-electric technician team at Nuojin Auto Parts, with over 15 years of hands-on experience in automotive charging and starting systems.
Our engineers specialise in Japanese, European, Korean, American and Chinese vehicle charging-system diagnostics, aftermarket alternator and starter-motor cross-referencing, and factory-spec electrical-system restoration for global markets. Every product listing on this site is backed by real bench-tested fitment data and first-hand repair experience, not just copied from manufacturer manuals.
If you have any question about this alternator or your engine charging system, contact our technical team and we will help you confirm the correct part for your application.
Nuojin Auto Parts is a professional starter and alternator supplier based in Hejian, Hebei, China, running factory-grade bench testing on every production batch. We support distributors, wholesalers and repair shops worldwide with correct-fit sourcing, a 1-year warranty and responsive after-sales technical assistance.
