Komatsu PC30-7 Swing Motor 708-7S-00022 20S-26-00020 | Tatan Machinery

Tatan Machinery supplies 100% Brand New hydraulic swing motor assemblies (OEM part numbers: 708-7S-00022 / 20S-26-00020, interchangeable with 708-7S-00040) engineered for Komatsu PC30-7, PC30R-7, and PC38UU-2 mini excavators. Mounted onto the upper revolving frame, this compact axial piston motor drives the slew reduction gearbox to rotate the cab and boom assembly. Built with an internal wet-disc parking brake pack and dual cushion shock-relief valves, each motor is 100% bench-tested for brake release pressure, starting torque, and case drain sealing. Backed by our 12-Month Comprehensive Replacement Warranty.

Supplier Information & Build Status

When to Replace the Swing Motor on Komatsu PC30-7: Field Diagnostics

Compact 3-ton excavators frequently dig trenches next to house walls and load trucks on cross-slopes. When internal motor wear occurs, replace the complete assembly under these severe symptoms:

• Upperstructure Creep & Slew Drift on Inclines: When parked on a driveway slope with joysticks in neutral, the bucket slowly drifts downhill. Internal brake friction plates are glazed, or valve plate micro-bypass is allowing oil leakage to tank.
• Violent Slew Stop Shock & Shudder: When releasing the swing joystick to dump dirt, the cab bounces backward violently with loud metallic clanking. The internal anti-reaction check valve springs are broken or relief orifices are plugged with debris.
• Sluggish Swing Acceleration Under Load: Slewing becomes extremely weak and hesitates when swinging a loaded mud bucket uphill. Excessive case-drain leakage indicates the cylinder barrel and brass slipper shoes have scored.
• Hydraulic Oil Leaking Past Shaft Seal into Slew Gearbox: Blown motor output shaft seal allowing pressurized hydraulic oil to flood down into the planetary slew gearbox, overfilling the gear grease cavity and blowing out through the top breather.

Workshop Bench Testing & 12-Month Warranty Guarantee

Every 100% Brand New 708-7S-00022 swing motor supplied by Tatan Machinery comes backed by a 12-Month Comprehensive Replacement Warranty. Before export packaging, our technicians complete a 5-point quality validation:

1. Slew Relief Pressure Calibration: Port overload relief cartridges calibrated to exact Komatsu PC30-7 factory specifications (19.6 MPa / 200 bar) on a digital motor test stand.
2. Mechanical Parking Brake Static Hold Test: Verifying the multi-disc wet friction brake firmly locks rotation at zero pilot pressure and releases cleanly when pilot signal is applied.
3. Anti-Reaction Damping Orifice Verification: Testing the cushion check valve flow curve to ensure smooth stopping without uncommanded swing bounce.
4. Case-Drain Internal Leakage Measurement: Precision flow-meter measurement at working oil temperature (55°C) to verify volumetric efficiency (>92%).
5. Drive Spline Shaft Hardness & Concentricity Check: Coordinate measurement of output shaft splines to ensure backlash-free engagement with the PC30-7 planetary slew gearbox.

Export Heavy-Duty Packaging Process

Precision motor rotating groups require absolute protection against moisture and freight shock:

• 100% Sealed Metal Port Caps: Main working ports, brake release pilot port, and case drain port fitted with heavy-duty metal blanking caps.
• Anti-Corrosion Wax Coating: Output drive splines and unpainted mounting pilots coated with heavy anti-rust grease and vacuum-sealed in VCI protective foil.
• Custom Molded Internal Framing: The motor is securely braced upright inside structural high-density wood cushioning.
• ISPM 15 Fumigation-Free Solid Plywood Box: Sealed export crate banded with galvanized steel straps.

Actual sealed port caps and heavy-duty crating for 708-7S-00022 swing motor

Global Shipping & Customs Documentation

Fast, reliable dispatch tailored for commercial contractors and parts wholesalers worldwide:

• Emergency Machine Down Air Cargo: Fast air express via DHL Aviation, FedEx Freight, or international airlines within 3–7 business days.
• Consolidated Ocean Sea Freight (LCL / FCL): Direct containerized shipping to worldwide commercial ports.
• Clean Customs Clearance Paperwork: Commercial Invoices with correct HS Code (8412.29 – Hydraulic Motors), Packing Lists, and Certificates of Origin for tariff optimization.

Container loading and air freight dispatch supported by global logistics partners

Critical Installation Guidelines (PC30-7 Slew Mechanic Checklist)

To prevent instant dry-run failure and protect your 12-month warranty, technicians MUST adhere to these critical procedures:

1. MANDATORY: Pre-Fill Motor Casing with Clean Hydraulic Oil: Before reconnecting hydraulic lines, remove the top case-drain plug and fill the motor casing completely with clean ISO VG 46 hydraulic oil. Running a new swing motor dry for even 3 seconds will instantly seize the rotating cylinder barrel!
2. Inspect Planetary Slew Reduction Gearbox Grease: Before bolting the motor down, check the gear grease/oil inside the reduction gearbox. Clean out any contaminated sludge and refill with fresh extreme-pressure gear grease.
3. Verify Parking Brake Release Pilot Pressure: Hook up a pressure gauge to the brake release port. Confirm that the pilot signal reaches at least 2.5–3.5 MPa when the swing joystick is moved, ensuring the brake friction discs release completely without dragging.
4. Case Drain Hose Inspection: Ensure the case drain hose returning to the hydraulic reservoir is 100% free of kinks or blockage. High drain backpressure will blow out the motor output shaft seal!
5. Bleed Air on Low-Idle Rotation: Operate the swing left and right at low engine idle for 5 minutes without hitting end-stops to purge all air from the relief manifold.

Buyer Frequently Asked Questions (Purchasing FAQ)

🔗 Frequently Purchased Together with Komatsu PC30-7 Swing Motor:

• DIESEL ENGINE:
  Komatsu PC30-7 3D84E Diesel Engine Assembly (YM729005-01560)
  Remanufactured
• MAIN VALVE:
  Main Control Valve Assembly (709-37-12101) for Komatsu PC30-7
  100% Brand New
• HYDRAULIC PUMP:
  Main Hydraulic Pump Assembly (705-41-08100) for Komatsu PC30-7
  100% Brand New
• FINAL DRIVE:
  Final Drive Travel Motor (20S-60-72120) for Komatsu PC30-7
  100% Brand New
• BRAND CATALOG:
  View All Komatsu Excavator & Heavy Equipment Parts Collection

Get Wholesale Factory Quote for PC30-7 Swing Motor 708-7S-00022

Looking for direct factory pricing, stock availability, or 12-month warranty terms for Komatsu PC30-7 swing motors? Contact senior specialist Gavin now!

💡 Fast Quote: Send your machine serial number or current motor nameplate photos for an accurate match within 10 minutes!