1. Introduction
This manual provides essential information for the safe and effective use of your Neiko 30128A 1/2 Inch Square Drive Air Impact Wrench. Please read all instructions carefully before operating the tool to ensure proper function and to prevent injury or damage.
The Neiko 30128A is a powerful pneumatic tool designed for various fastening and loosening applications in automotive and workshop environments. It features a twin hammer mechanism for high torque output and an ergonomic design for user comfort and control.
2. Safety Information
WARNING: Failure to follow these safety instructions may result in serious personal injury or property damage.
- Always wear ANSI-approved safety glasses or goggles and hearing protection when operating this tool.
- Disconnect the air supply before changing accessories, performing maintenance, or when the tool is not in use.
- Do not exceed the recommended air pressure of 90 PSI.
- Keep hands and body parts clear of moving parts during operation.
- Ensure the workpiece is securely fastened before applying the tool.
- Use only impact-rated sockets and accessories with this tool.
- Do not operate the tool if it is damaged or malfunctioning.
- Keep children and bystanders away from the work area.
3. Setup
- Air Supply Connection: Connect the air impact wrench to an air compressor with a minimum of 3 HP and a regulated air pressure of 90 PSI. The tool features a 1/4 inch NPT air inlet. Use an air hose with a minimum 3/8 inch inner diameter for optimal performance.
- Lubrication: Before each use, add a few drops of pneumatic tool oil into the air inlet. This ensures proper lubrication of internal components and extends tool life.
- Attach Socket: Select the appropriate 1/2 inch drive impact-rated socket for your application and firmly attach it to the square drive anvil of the wrench.

4. Operating Instructions
- Directional Control: The tool is equipped with a directional switch, typically located near the trigger, allowing you to easily switch between clockwise (forward) and counter-clockwise (reverse) rotation. Select the desired direction for fastening or loosening.
- Applying the Tool: Place the socket firmly onto the fastener. Ensure the socket is fully engaged to prevent stripping the fastener or damaging the socket.
- Activating the Tool: Depress the trigger to activate the impact wrench. The tool will deliver powerful, balanced impacts to tighten or loosen the fastener. Release the trigger to stop operation.
- Torque Application: The Neiko 30128A provides a maximum breakaway torque of 600 ft-lb and a working torque of 450 ft-lb. For critical applications requiring precise torque, always use a calibrated torque wrench for final tightening.



5. Maintenance
- Daily Lubrication: Add 5-10 drops of pneumatic tool oil into the air inlet before each use. This is critical for the longevity and performance of the tool.
- Air Line Inspection: Regularly inspect air lines, hoses, and connections for leaks, wear, or damage. Replace any damaged components immediately.
- Cleaning: Keep the exterior of the tool clean and free from debris. Use a clean cloth to wipe down the tool after each use. Do not use harsh chemicals or solvents.
- Storage: Store the air impact wrench in a clean, dry environment when not in use. Protect it from moisture and extreme temperatures.
6. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Low power or slow operation | Insufficient air pressure or volume; lack of lubrication; worn internal parts | Check air compressor output and regulator setting (ensure 90 PSI); add pneumatic tool oil; inspect air hose for kinks or small diameter; consult a qualified technician for internal inspection. |
| Air leaks from tool | Loose fittings; damaged O-rings or seals | Tighten all air fittings; replace damaged O-rings or seals. |
| Tool does not operate | No air supply; trigger mechanism jammed; severe internal damage | Ensure air supply is connected and turned on; check trigger for obstructions; if problem persists, seek professional service. |
7. Specifications
| Feature | Detail |
|---|---|
| Model Number | 30128A |
| Drive Size | 1/2 Inch Square |
| Recommended Air Pressure | 90 PSI |
| Recommended Air Compressor | 3 HP |
| No-Load Speed | 7500 RPM |
| Maximum Torque | 600 ft-lb |
| Working Torque | 450 ft-lb |
| Air Inlet | 1/4 Inch NPT |
| Hose ID | 3/8 Inch |
| Average Air Consumption | 6.5 CFM |
| Material | Aluminum |
| Dimensions (L x W x H) | 21.21 x 19.51 x 7.9 cm |
| Weight | 2.43 kg |
| UPC / GTIN | 816914022553 |
8. Warranty Information
Neiko products are manufactured to high-quality standards. For specific warranty terms and conditions applicable to your Neiko 30128A Air Impact Wrench, please refer to the warranty card included with your purchase or visit the official Neiko website. Keep your proof of purchase for any warranty claims.
9. Support
For technical assistance, replacement parts, or customer service inquiries regarding your Neiko 30128A Air Impact Wrench, please contact Neiko customer support through their official website or the contact information provided in your product packaging. When contacting support, please have your model number (30128A) and purchase date available.