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707-99-72320 Boom Cylinder Seal Kit For Komatsu Excavator | Ruijueparts

707-99-72320 Boom Cylinder Seal Kit For Komatsu Excavator | Ruijueparts

Regular price $36.34
Regular price Sale price $36.34
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Availability1000 in stock

Volume discounts available · Minimum order quantities apply for bulk pricing

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SKU: 707-99-72320
Vendor: RuiJueParts

Shipping & Returns

Shipping:
- Standard models take 1-3 business days.
- Bulk orders take 3-7 business days.
- For urgent orders, please contact our sales team. [Email: info@ruijueparts.com]

Returns:
We accept returns within 30 days of purchase. Learn more—return policy

Packaging details

PP bag, carton

Place of Origin

China

Payment terms

L/C, T/T, Western Union, MoneyGram

Performance

Oil Sealing

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    Product Description

    Keep your hydraulic systems running at peak efficiency with the high-quality 707-99-72320 Boom Cylinder Seal Kit from Ruijueparts. Designed as a premium aftermarket replacement for Komatsu heavy machinery, this repair kit contains all the essential wear-resistant components required to prevent fluid leaks, safeguard sensitive systems against dirt and dust, and restore reliable pressure to your excavator's boom cylinder. We understand that fleet downtime is costly; therefore, our seals are sourced from precision manufacturers to match original operational parameters without the OEM price tag. Whether you are maintaining a modern fleet or extending the service life of an older model, this comprehensive kit ensures simple maintenance, precise fitment, and long-term durability in severe working environments.

    Item specifics

    Part Number: 707-99-72320
    Fits Models: PC450-8 S/N 70001-UP, PC400-7 S/N 50001-UP
    Brand: KOMATSU replacement
    Type: Boom Cylinder Seal Kit / Hydraulic Cylinder Seal Kit
    Application:

    This premium aftermarket 707-99-72320 Boom Cylinder Seal Kit is precision-engineered to fit the following Komatsu heavy excavator models:

    • PC400-8 / PC400LC-8 (Standard & Long Crawler Hydraulic Excavators)

    • PC450-8 / PC450LC-8 (Heavy Duty & Long Crawler Hydraulic Excavators)

    Size: Standard Size


    FAQ

    • Q1: Is this 707-99-72320 seal kit an original Komatsu part?
      A: No, this is a premium quality aftermarket replacement kit manufactured to meet or exceed the performance specifications of the original equipment. It offers a cost-effective, high-durability solution without compromising on machinery safety.
    • Q2: How can I confirm if this kit precisely fits my specific Komatsu model?
      A: With access to our cross-reference database containing over 30,000 part numbers, our team can verify compatibility for you. Simply provide us with your equipment model and machine serial number before purchasing, and we will confirm the exact fitment.
    • Q3: Do you offer custom sealing solutions or flexible packaging options for large orders?
      A:
      Yes, we specialized in supporting older or legacy machinery with custom-tailored sealing solutions. Additionally, we provide flexible packaging choices—we can deliver items in neutral packaging to protect your market privacy or customize the packaging according to your specific branding requirements.

    Why choose Ruijueparts

    Lower cost — honest trade-off

    Our aftermarket seal kits deliver a practical, cost-effective solution without compromising on real-world performance. We offer a lower upfront cost and reliable sealing for your daily maintenance and repair needs.

    Extensive part number range

    We stock seal kits across CAT, Komatsu, Volvo, JCB, Hitachi, Doosan, John Deere, Kubota, and 10+ other brands—one supplier for your whole fleet.

    Flexible packaging options

    Ship under RuijueParts branding, neutral (unbranded) packaging, or your own private label. Suitable for resellers and distributors.

    Customization Service

    When genuine OEM seals are out of production for your old machinery, we can custom-make oil seals using your dimensions or our engineer-recommended specifications.

    Wholesale & OEM bulk orders

    Ship under RuijueParts branding, neutral (unbranded) packaging, or your own private label. Suitable for resellers and distributors.

    Warranty on request

    Volume pricing for repair shops, dealers, and fleet operators. Get a quote via our website or WhatsApp: +86 13692100161.

    When budget aftermarket makes sense

    OEM seal kits are the right choice when machinery is under active warranty, operating at peak duty cycles, or when failure risk is unacceptably high. Budget aftermarket—like Ruijue Parts—makes sense in these common scenarios:

    Older or end-of-life equipment

    When a machine is aging out of your fleet, OEM parts cost more than the job warrants. A budget kit extends service life without over-investing.

    Secondary or backup machines

    For machines used infrequently or on lower-intensity tasks, premium OEM pricing may not be justified.

    OEM parts unavailable or on long lead time

    When OEM stock is out or delivery takes weeks, an available aftermarket kit gets your machine running now.

    Fleet maintenance on a fixed budget

    Repair shops and fleet managers running high volumes of machines often balance OEM and aftermarket across their portfolio based on criticality.

    Installation guide

    1. Depressurize the hydraulic system

    Fully retract the cylinder and relieve system pressure before disassembly. Never work on a pressurized circuit.

    2. Remove and disassemble the cylinder

    Remove from the machine. Unthread the gland nut and withdraw the piston rod carefully to avoid surface damage.

    3. Clean all components thoroughly

    Clean the bore, rod, and all metal parts with a lint-free cloth. Contamination introduced during reassembly accelerates seal wear—this step is especially important for budget-grade seals.

    4. Inspect the rod and bore

    Check for scoring or pitting. Budget seals are more sensitive to surface imperfections—address rod damage before fitting new seals.

    5. Install the seal kit

    Lightly coat each seal with clean hydraulic fluid before installation. Use proper seal drivers — not screwdrivers or sharp tools — to avoid nicking the sealing lip.

    6. Reassemble and pressure test

    Torque the gland nut to spec and cycle the hydraulic system under no-load conditions. Inspect for leaks before returning the machine to service.

    Maintenance tips

    Inspect every 250–500 hours

    Budget-grade seals may have shorter service intervals than OEM. Inspect rod seals for moisture, oil film, or weeping more frequently and replace proactively.

    Keep hydraulic fluid clean

    Contaminated fluid degrades seals faster — this applies especially to non-OEM materials. Replace fluid and filters on schedule.

    Protect exposed rod surfaces

    When storing equipment with cylinders extended, protect rod surfaces from corrosion and debris to preserve wiper seal life.

    Ensure Proper Installation

    Avoid using sharp tools during assembly to prevent nicks or scores on the seal lips. Pre-lubricating all components with clean hydraulic oil is recommended to ensure a smooth fit into the cylinder grooves.

    Reduce Downtime with Reliable Seals.

    Click "Add to Cart" for immediate dispatch, or contact our team for bulk pricing and wholesale support.

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