Komatsu PC120-3 Excavator Hydraulic Arm Cylinder 203-63-62500 105mm Bore Aftermarket
PC120-3 Hydraulic Arm Cylinder for Komatsu Excavator | PN:203-63-62500 | Premium Aftermarket Replacement
1. Basic Product Info
This high-strength aftermarket hydraulic arm (stick) cylinder is precision manufactured as a direct replacement spare part for Komatsu PC120-3 medium excavators. As the core hydraulic actuator of front working attachment, it controls arm extension and retraction to finish digging, material grabbing, loading and land leveling works. Widely used in municipal projects, road maintenance, landscaping and small quarry earthmoving jobs.
All cylinders are produced strictly following Komatsu OEM technical standards, with identical mounting dimensions, pin hole spacing and hydraulic port layout. Direct bolt-on installation on site without cutting, welding or any secondary modification.
| Item | Specification |
|---|---|
| Product Name | Hydraulic Arm (Stick) Cylinder |
| Applicable Model | Komatsu PC120-3 Excavator |
| OEM Part Number | 203-63-62500 |
| Product Grade | Brand New High-Quality Aftermarket |
| Warranty | 12 months against manufacturing defects |
| MOQ | 1 unit, sufficient stock for immediate shipment |
| QC Standard | ISO9001 certified, full hydraulic pressure & cyclic fatigue testing before delivery |
2. Core Technical Parameters
| # | Part No. | Description | Qty |
|---|---|---|---|
| 1 | 203-63-62500 | ARM CYLINDER ASS'Y | 1 |
| 1 | 203-63-62540 | Cylinder | 1 |
| 2 | 203-63-62520 | ROD,PISTON | 1 |
| 3 | 707-28-11370 | HEAD,CYLINDER | 1 |
| 4 | 144-63-94170 | SEAL,DUST (KIT) | 1 |
| 5 | 07179-00097 | RING, SNAP | 1 |
| 6 | 07177-07530 | Bushing | 1 |
| 7 | 707-51-75211 | PACKING,ROD (KIT) | 1 |
| 9 | 07000-12105 | O-RING, STEERING PUMP MOUNTING | 2 |
| 10 | 07146-02106 | RING, BACK-UP (KIT) | 2 |
| 11 | 707-35-91110 | RING,BACK-UP (KIT) | 1 |
| 12 | 01010-51655 | BOLT,(FOR REINFORCED TYPE) | 12 |
| 13 | 707-36-11460 | Piston | 1 |
| 14 | 707-68-10580 | Nut | 1 |
| 15 | 707-44-11080 | RING,PISTON (KIT) | 1 |
| 16 | 07155-01125 | RING,WEAR (FOR WA120-1M) | 1 |
| 17 | 707-76-70130 | Bushing | 2 |
| 18 | 07145-00070 | SEAL,DUST? PISTON ROD | 4 |
| 19 | 707-40-11470 | Retainer | 1 |
| 20 | 707-71-50880 | PLUNGER | 1 |
| 21 | 707-71-50230 | PLUNGER | 1 |
| 22 | 707-71-91250 | Screw | 1 |
| 23 | 04260-00635 | BOWL, CHECK VALVE | 11 |
| 24 | 203-63-62570 | Tube | 1 |
| 25 | 01010-50855 | BOLT,(10M) | 2 |
| 26 | 01010-50845 | Screw | 2 |
| 27 | 01602-20825 | WASHER,SPRING?FOR ADDITIONAL REAR LAM | 4 |
| 28 | 07000-13030 | O-RING,BOOM (FOR 50 FEET LONG FRONT) | 1 |
| 29 | 707-88-99150 | BAND | 1 |
| 30 | 707-88-99120 | BAND | 1 |
| 31 | 707-88-99190 | BAND | 1 |
| 32 | 707-88-99110 | BAND | 1 |
| 33 | 07282-02793 | Clamp | 2 |
| 34 | 01010-51020 | BOLT,(FOR QUICK SHIFT) (MITSUBISHI) | 4 |
| 35 | 01010-51030 | BOLT,(FOR QUICK SHIFT) (MITSUBISHI) | 4 |
| 36 | 01602-21030 | WASHER, SPRING (SUPPLIED W/SPIDER ASSEMBLY) | 8 |
| Spec Item | Data |
|---|---|
| Bore Diameter | 105mm |
| Piston Rod Diameter | 70mm |
| Working Stroke | 1130mm |
| Rated Working Pressure | 31.4MPa |
| Factory Test Pressure | 47.1MPa (1.5 times rated working pressure) |
| Barrel Material | High-tensile seamless alloy steel with precision inner honing |
| Piston Rod | 40CrMo heat-treated steel, 28~32μm hard chrome plating, HRC68~72, excellent wear & anti-deformation performance |
| Matching Seal Kit PN | 203-63-62500K |
| Working Temperature | -25℃ ~ +85℃ |
| Structure | Double ear lugs with quenched copper wear bushings, built-in buffer device to reduce reciprocating impact |
3. Product Advantages
- 100% OEM Perfect Interchange Fitment
All assembly sizes, lug spacing and oil port positions fully match original PN 203-63-62500 cylinder. Seamlessly connects arm linkages and hydraulic pipelines for stable continuous medium-load operation. - Medium-Load Reinforced Structure
Thickened cylinder tube and connecting lugs are optimized for daily construction scenarios, resisting frequent dynamic loads and minor collisions to extend service life effectively. - Multi-Round Strict Pre-Delivery Inspection
Each finished cylinder undergoes full-stroke reciprocating cycle test and high-pressure airtight leak detection, completely eliminating internal and external oil leakage hidden risks. - Excellent Cost Performance
Provides the same stability and service lifespan as genuine Komatsu OEM spare parts, greatly cutting repeated purchasing costs for repair shops and spare parts wholesalers. - Flexible Global Logistics Support
In-stock goods ship out within 3 working days. Air freight for urgent breakdown orders; sea freight for low-cost bulk wholesale shipments to Africa, Southeast Asia, Middle East.
4. Supplier Brief
Our factory has more than ten years of mature experience in developing and manufacturing hydraulic cylinders for classic Komatsu PC series excavators including PC120-3. We supply complete boom, arm and bucket cylinder assemblies with mature production craft and full-process strict quality control systems. Our aftermarket hydraulic cylinders are exported to global aftermarket markets all year round, earning long-term trust and consistent favorable feedback from worldwide spare parts dealers.
5. FAQ
Q1: Can this arm cylinder fit Komatsu PC100-3 or PC120-5 excavators?
A: No. Each Komatsu excavator model adopts exclusive part numbers and unique structural dimensions without interchangeability. Please confirm your full machine model before placing orders.
Q2: Does the standard package include the matching seal repair kit?
A: Seal repair kit is not included in standard delivery. You can purchase the dedicated supporting seal kit separately, and we will offer a competitive combined order quotation.
Q3: What packaging is used for long-distance overseas sea transportation?
A: Anti-rust oil filled into cylinder inner cavity, anti-rust grease evenly coated on piston rod surface. The whole cylinder wrapped with waterproof PE film and packed in reinforced export plywood cases to avoid collision, scratch and moisture damage during long ocean transit.
Q4: Are there tiered volume discounts when purchasing a full set of boom + arm + bucket cylinders?
A: Yes. Complete working device cylinder set orders enjoy graded volume discounts. Consolidated container shipment service is available to lower total logistics expenses.
Q5: What after-sales support if oil leakage occurs within warranty period?
A: Please provide clear photos of leakage position plus excavator serial number. We will arrange free seal replacement and professional remote troubleshooting guidance promptly.
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.