Introduction
This manual provides essential information for the safe and effective use of the Greenlee 156555 Hydraulic Spool/Shuttle. Please read this manual thoroughly before installation, operation, or maintenance to ensure proper function and safety.
The Greenlee 156555 is a component designed for integration into hydraulic systems, functioning as a spool or shuttle mechanism. Its primary purpose is to control the flow or direction of hydraulic fluid within a system.
Safety Information
Always observe general safety precautions when working with hydraulic equipment. Hydraulic systems operate under high pressure and can cause serious injury if not handled correctly.
- Ensure all hydraulic lines are depressurized before attempting installation or maintenance.
- Wear appropriate personal protective equipment (PPE), including eye protection and gloves.
- Verify that the component is compatible with your hydraulic system's pressure and fluid type.
- Consult a qualified hydraulic technician if you are unsure about any installation or operation procedures.
Product Overview

Figure 1: The Greenlee 156555 Hydraulic Spool/Shuttle. This image displays the metallic body of the spool/shuttle, featuring a hexagonal base for secure wrenching and a brass-colored cylindrical top section, separated by a dark sealing ring. The lower part of the component has a threaded or ribbed texture.
Setup and Installation
- Depressurize System: Before beginning installation, ensure the hydraulic system is completely depressurized and locked out to prevent accidental activation.
- Inspect Component: Carefully inspect the Greenlee 156555 for any signs of damage or manufacturing defects. Ensure all seals and threads are clean and intact.
- Prepare Mounting Location: Identify the correct port or manifold location for the spool/shuttle within your hydraulic circuit. Clean the mating surfaces thoroughly.
- Install Spool/Shuttle: Thread the spool/shuttle into the designated port. Hand-tighten first, then use an appropriate wrench on the hexagonal base to secure it. Do not overtighten, as this can damage threads or seals. Refer to your system's specifications for torque requirements.
- Connect Hydraulic Lines: Attach any necessary hydraulic lines or fittings to the spool/shuttle, ensuring all connections are secure and leak-free.
- System Bleeding and Testing: After installation, slowly repressurize the hydraulic system. Bleed any air from the lines as per your system's guidelines. Carefully check for leaks around the newly installed component and monitor its function during initial operation.
Operating Instructions
The Greenlee 156555 functions as a control element within a hydraulic circuit. Its operation is typically integrated into the overall system's control logic, rather than being a standalone user-operated device.
- System Integration: The spool/shuttle's movement or position will be dictated by pressure differentials or external actuation signals from the hydraulic system.
- Fluid Direction/Flow Control: Depending on its design, the spool/shuttle will direct hydraulic fluid to specific actuators or control the rate of fluid flow.
- Monitor System Performance: During operation, observe the hydraulic system for proper function, including pressure, flow rates, and actuator response. Unusual noises or sluggish operation may indicate an issue.
Refer to the complete hydraulic system's operational manual for specific instructions on how this component interacts with other parts of your equipment.
Maintenance
Regular maintenance ensures the longevity and reliable performance of the Greenlee 156555 and the entire hydraulic system.
- Fluid Quality: Maintain clean hydraulic fluid. Contaminants are a leading cause of hydraulic component failure. Follow recommended fluid change intervals and filtration practices.
- Leak Inspection: Periodically inspect all connections, including the spool/shuttle, for any signs of hydraulic fluid leaks. Address leaks immediately.
- Seal Replacement: Over time, seals may degrade. If leaks persist or performance degrades, the internal seals of the spool/shuttle may need replacement. This typically requires specialized tools and expertise.
- Component Cleaning: If the component is removed for maintenance, clean it thoroughly with appropriate hydraulic cleaning solutions. Avoid harsh chemicals that could damage seals.
Troubleshooting
If the hydraulic system experiences issues, consider the following general troubleshooting steps related to the spool/shuttle component:
- No Flow/Reduced Flow:
- Check for blockages in hydraulic lines or within the spool/shuttle itself.
- Verify correct system pressure.
- Inspect for a stuck or improperly seated spool.
- Leaks:
- Tighten connections to specified torque.
- Inspect seals for damage or wear; replace if necessary.
- Check for cracks in the component body (rare, but possible).
- Erratic Operation:
- Air in the hydraulic system.
- Contaminated hydraulic fluid affecting spool movement.
- Incorrect pressure settings.
For complex issues, consult the complete hydraulic system's service manual or contact a qualified technician.
Specifications
| Attribute | Value |
|---|---|
| Brand | Greenlee |
| Model Number | 156555 |
| Part Number | 156555 |
| Item Weight | 0.16 ounces |
| Package Dimensions | 9 x 6 x 0.38 inches |
| Included Components | 1 Greenlee Branded Product |
| Batteries Required? | No |
| ASIN | B004OG0DIA |
| UPC | 783310435464 |
Warranty Information
Specific warranty details for the Greenlee 156555 Hydraulic Spool/Shuttle are not provided in this manual. For comprehensive warranty information, please refer to the official Greenlee website or contact Greenlee customer service directly. Retain your proof of purchase for warranty claims.
Customer Support
For technical assistance, replacement parts, or further inquiries regarding the Greenlee 156555, please contact Greenlee customer support:
- Manufacturer: Greenlee Tools, Inc.
- Website: www.greenlee.com (Please visit the official website for current contact information and support resources.)





