CAT 320C 320D 200-3269 244-8483 SBS120 Hydraulic Pump Parts Kit Pistons Shaft Compatible with Cater.pillar

1. Product Overview & Wholesale Price Range

The Cater.pillar SBS120 Hydraulic Main Pump Parts Kit with Pistons, Valve Plates & Shaft (OEM Part # 200-3269 / 244-8483 / 259-0815 / SBS120) includes the complete internal rotary overhaul set: forged drive shaft, cylinder block, piston shoes with bronze slippers, distributor valve plate (RH/LH), retainer plate, ball guide, and swash plate cradle designed for 20-ton excavators undergoing hydraulic pump overhauls.

• Factory Wholesale Price: $380 – $850 USD (Direct manufacturer pricing — Save up to 50% vs regional dealer markups)
• Included Core Spare Parts: Forged Drive Shaft (1pc) + Cylinder Block (1pc) + Piston Shoes (9pcs) + Valve Plate (1pc) + Retainer Plate (1pc) + Ball Guide (1pc) + Swash Plate Cradle (1pc)
• MOQ & Bulk Discount: 1 Set (Tiered wholesale discounts available for hydraulic repair shop batch orders)
• Lead Time: 1–3 business days (Large factory stock ready for immediate worldwide dispatch)
• Warranty: 12 Months full replacement warranty with high-lead bimetallic bronze durability guarantee

2. Application Worksite Checklist (施工场景清单)

Engineered to restore original torque transmission and hydraulic working pressure across demanding 20-ton excavator jobsites:

• Heavy Open-Pit Quarrying & Mining: Precision heat-treated drive shaft splines withstand continuous 350 Bar shock torque during heavy rock digging with CAT 320D excavators.
• Deep Foundation Excavation & Earthmoving: High thermal resistance bimetallic valve plates prevent internal power loss during continuous long-hour operation.
• Highway Infrastructure & Utility Trenching: Micro-lapped cylinder faces ensure zero internal oil bypass during fast bucket loading cycles.
• Demolition & Heavy Breaker Operations: Case-hardened alloy steel pistons absorb continuous high hydraulic pressure shockwaves from breaker hammer attachments.

3. Hydraulic Pump Parts Kit Troubleshooting & Diagnostic Guide (泵配件/柱塞/传动轴常见故障排查)

If your CAT 320C / 320D excavator main pump is exhibiting driving or pressure loss symptoms, consult the diagnostic guide below:

• Fault 1: Drive Shaft Spline Wear, Stripping or Torque Transmission Slippage (传动轴花键磨损/打滑断裂)
  Root Cause: Extreme torsional fatigue, engine flywheel misalignment, or lack of spline lubrication over long continuous mining operations.
  Solution: Replace with our induction-hardened forged alloy drive shaft and complete SBS120 rotor assembly (OEM 200-3269).
• Fault 2: Thermal Pressure Loss & Machine Slowdown After 1 Hour (热车掉压发慢/内泄)
  Root Cause: Wear gap between the cylinder block face and valve plate surface causing internal high-pressure thermal oil bypass.
  Solution: Replace the worn rotary group with our precision lapped SBS120 cylinder block and valve plate kit (OEM 244-8483).
• Fault 3: Engine Stalls or Lacks Digging Force Under Heavy Bucket Load (憋车熄火/无力)
  Root Cause: Scoring on piston shoe brass slippers or stickiness in the swashplate cradle pivot.
  Solution: Install new SBS120 copper-coated piston shoes and swashplate group to restore smooth stroke control.
• Fault 4: Black Copper Filings Found in Hydraulic Tank Oil Filter (油箱内有黑粉铜屑)
  Root Cause: Friction galling and thermal melting of the bronze layer on the piston slippers.
  Solution: Flush the entire hydraulic oil system, clean main control valve, and rebuild pump with a new SBS120 parts kit.

4. Hot Machinery Replacement Parts Recommendation (5大品类热门推荐表)

Explore our factory-direct replacement hydraulic components compatible with major global excavator brands:

5. Frequently Asked Questions & Technical Support (QA 问答专区)

Q1: How do I verify if this SBS120 parts kit with pistons and drive shaft fits my CAT 320C or 320D excavator main pump?
A: Check your original pump nameplate for OEM part numbers 200-3269, 244-8483, or SBS120 stamp. You can also count the spline teeth on your old drive shaft and send us photos for instant fitment verification.

Q2: What is the material hardness and forging spec of the SBS120 drive shaft in this kit?
A: Our SBS120 drive shafts are forged from 40CrMo alloy steel with high-frequency induction hardened splines (HRC 58-62) to resist extreme torsional torque and prevent spline stripping.

Q3: Is this SBS120 parts kit a complete overhaul solution for main pump rebuilds?
A: Yes, it includes all major internal wear components (forged drive shaft, cylinder block, 9 pistons, valve plate, retainer plate, ball guide, and swashplate cradle) required for a complete pump rebuild.