19 GPM Rated Flow • 4,000 PSI Maximum • 1/2" Keyed Shaft • Right-Angle Suction Fitting Included

Upgrade or replace the hydraulic pump on a compatible log splitter with the WSD31-254 Two-Stage Hydraulic Pump. Designed for high-flow open-center hydraulic systems, this OEM-grade replacement pump provides fast cylinder movement during low-resistance travel and automatically shifts to lower-flow, high-pressure operation when the wedge encounters difficult wood.

The pump is rated at 19 GPM at 3,600 RPM and is intended for direct-drive use with a horizontal-shaft gasoline engine rated at 9.5 HP or greater. A 90-degree suction fitting is included to simplify installation in compatible hydraulic systems.

Key Features & Benefits

• High-Flow 19 GPM Performance
  Provides substantial hydraulic flow for faster wedge extension and return on properly matched log splitters.
• Automatic Two-Stage Operation
  Combines high flow at lower pressure with lower flow at higher pressure, helping deliver fast cycle times without requiring an oversized engine.
• Up to 4,000 PSI Maximum Pressure
  Supports demanding splitting applications when installed in a properly designed hydraulic system.
• 16.5 GPM First Stage
  The high-flow stage operates at a published 650 PSI for rapid cylinder travel under lighter resistance.
• 3.6 GPM Second Stage
  The high-pressure stage supplies lower flow at a published 2,500 PSI when greater splitting force is needed.
• Minimum 9.5 HP Engine Requirement
  Designed for direct-drive use with a compatible horizontal-shaft gasoline engine.
• 1/2" Keyed Drive Shaft
  Accepts a properly sized flexible coupling designed for a 1/2-inch pump shaft and 1/8-inch Woodruff key.
• Right-Angle Suction Fitting Included
  The supplied 90-degree pickup fitting helps route the hydraulic suction line in installations with limited clearance.
• Clockwise Rotation
  Rotates clockwise when viewed from the engine toward the pump shaft face.
• Open-Center Systems Only
  Intended for log splitters and other hydraulic equipment using an open-center control valve.
• OEM-Grade Replacement Configuration
  Designed to fit many current log splitter hydraulic systems when the shaft, ports, mounting pattern, rotation, and engine requirements match.

How the Two-Stage Pump Works

During normal wedge travel, the pump’s high-flow section moves the cylinder quickly toward or away from the log. When resistance increases, the pump automatically unloads the high-flow section and continues operating with the lower-flow, high-pressure stage.

This design provides the combination of speed and splitting force needed for log splitter operation while reducing the engine horsepower required compared with a similarly sized single-stage pump. Once hydraulic resistance decreases, the pump returns to high-flow operation.

Ideal Applications

The WSD31-254 may be used in compatible:

• Hydraulic log splitters
• Hydraulic presses
• Clamping systems
• Compactors
• Custom open-center hydraulic equipment
• Log splitter repair and rebuilding projects

Compatibility depends on the engine horsepower, shaft size, coupling, rotation, mounting pattern, port sizes, flow requirements, and hydraulic-system design.

Quick Specifications

The outlet requires a standard 1/2-inch NPT fitting rather than an ORB O-ring fitting.

Pump Displacement

Tool Tuff publishes the following displacement figures for the two pump sections:

• Low-flow pump section: 0.256 cu. in. per revolution
• High-flow pump section: 0.793 cu. in. per revolution

These stages work together during low-pressure cylinder travel, while the smaller section continues supplying flow after the high-volume stage unloads.

Package Contents

• One WSD31-254 two-stage hydraulic pump
• One 90-degree suction pickup fitting

The engine, pump mount, flexible coupling, hydraulic hoses, outlet fitting, control valve, reservoir, filter, mounting hardware, and hydraulic fluid are not listed as included.

Important Compatibility Information

This pump is not universal. Before ordering, verify:

• Engine is rated at 9.5 HP or greater
• Engine operates at approximately 3,600 RPM
• Engine has a horizontal output shaft
• Flexible coupling accepts a 1/2-inch keyed pump shaft
• Pump mount matches the four-bolt pattern
• Pump rotation is clockwise
• Suction line matches the 1-inch inlet
• Pressure line uses a 1/2-inch NPT fitting
• Control valve is designed for an open-center system
• Reservoir, filter and hoses can support the required flow
• All hydraulic components are rated for the system pressure

Do not install an ORB-style O-ring fitting in the NPT outlet port. Using an incompatible fitting can damage the port or create a high-pressure hydraulic leak.