COGENG Komatsu 707-98-34580 PAT Lift Cylinder Seal Kit Fits Komatsu D61EX-12 D61PX-12

Technical Constants & Performance Data

Exact Model Compatibility

Component Specifications Table

Specific Components Included

• Main Piston Seal (U-Cup) – Qty: 1

• Rod Seal (Step Seal) – Qty: 1

• Wiper/Scraper – Qty: 1

• Buffer Ring – Qty: 1

• Wear Ring (Piston) – Qty: 1

• Complete O-Ring & Backup Ring Set – Qty: 1 Set (All necessary sizes for gland and port assembly)

• Note: This kit provides a complete seal profile set designed to match the exact specifications of the original Komatsu 707-98-34580 PAT lift cylinder kit. An exploded diagram is included for correct assembly.

Support Seals & Hardware

• Full set of precision-molded static O-rings for all gland and port connections

• Essential wear guide band to ensure smooth piston travel and minimize side load on seals

• Required high-pressure nylon backup rings

• Excluded Items: This is a seal and wear component kit only. It does NOT include the piston, cylinder rod, barrel, gland nut, bearings, bolts, pins, or any other metal parts or hardware.
  Critical Specific Warnings

• MODEL-SPECIFIC APPLICATION: This kit is ONLY for the PAT LIFT CYLINDERS on Komatsu D61EX-12 and D61PX-12 crawler dozers. Do not use on angle cylinders, tilt cylinders, or other dozer models without verification. Incorrect application will cause failure.

• METAL SURFACE CONDITION: This kit seals fluid between precision metal surfaces. It CANNOT repair a scored rod or a worn cylinder bore. Installation on damaged components will result in immediate, severe leakage.

• EXTREME ABRASIVE ENVIRONMENT: Dozer lift cylinders are constantly exposed to dirt and debris. Absolute cleanliness during assembly is non-negotiable to prevent rapid abrasive seal wear upon startup.

• CONTAMINATION CONTROL: Even microscopic debris introduced during assembly will act as an abrasive, destroying new seals. Maintain meticulous cleanliness throughout the repair process.

• LOAD SUPPORT HAZARD: The bulldozer blade must be fully lowered and supported by the ground. Never work on a cylinder that is under load or hydraulic pressure.
  Compatibility & Application Data

Application Sector	Machine Series	Cylinder Type	Symptoms Addressed
Heavy Earthmoving & Grading	Komatsu D61EX-12 / D61PX-12	PAT Lift Cylinders	Inability to hold blade height ("drift" or "sinking"), visible hydraulic oil leakage from the rod gland, slow or weak blade lifting power, oil pooling under the machine
Construction & Site Development	Komatsu D61-12 Series Dozers	Blade Lift/Hoist Control	Loss of precise grade control, increased hydraulic fluid consumption, reduced machine pushing efficiency and productivity
Mining & Quarry Operations	Komatsu D61-12 Crawler Dozers	Hydraulic Implement Systems	Reduced equipment efficiency, increased maintenance costs, unplanned downtime
Equipment Maintenance	Scheduled Overhauls & Leak Repair	PAT Lift Cylinder Rebuild	Restores factory sealing for reliable blade control, prevents environmental fluid loss, cost-effective OEM alternative

Installation decomposition diagram


installation Guidelines & Critical Procedures

1. Application Verification: Confirm 707-98-34580 is the correct kit for your D61EX-12 or D61PX-12 PAT lift cylinders.

2. System Depressurization: Park the dozer on level ground. Lower the blade fully to relieve all hydraulic pressure. Engage parking brake and block tracks securely.

3. Clean Work Environment: Maintain surgical cleanliness throughout the repair process. Dozer environments are highly abrasive; contamination control is essential.

4. Documented Disassembly: Carefully disassemble the PAT lift cylinder. Photograph and note the exact order and orientation of all components, especially the seal stack in the gland.

5. Critical Metal Inspection: Use precision tools to inspect the cylinder rod for any scratches, gouges, or corrosion. Check the cylinder bore (ID) for scoring, pitting, or excessive wear. Damaged metal components MUST be reconditioned or replaced prior to seal installation.

6. Lubricated Assembly: Soak all new elastomeric seals in clean hydraulic fluid. Lightly lubricate all seal grooves and sliding surfaces before installing new seals.

7. Proper Tool Use: Use seal installation tools (cone tools, picks, sleeves) to carefully install seals without cutting, stretching, or rolling them over sharp edges.

8. Torque to Specification: During reassembly, use a calibrated torque wrench. Adhere strictly to Komatsu's specified torque values and sequences for gland bolts or end caps.

9. System Testing: After assembly, perform a controlled pressure test to validate seal integrity before returning to service.
   Frequently Asked Questions

A. When will get the items after I place order?
Q. Once your payment is confirmed,we will arrange the goods within 1~4 days; if not in stock, we will inform you before placing the order?
A. If I only know the excavator model, but can not offer parts No.,what should I do ?
Q. If possible, you can send us pictures of old products, nameplate or the size for reference.
A. How can you guarantee the quality??
Q. We will 100% test the goods before delivery. We also support video inspection.
A. How long will it take to delivery to my address??
Q. The normal delivery time is 3-7 days, depending on which country you are in.?
A : Which delivery method will you choose?
Q : By sea, air or express(DHL,Fedex,TNT, UPS, EMS etc.)，Sometimes we will arrange as the customer's demand.
A: What's package? Can you give me the package according my requirement??
Q. We usually packed by standard exported box or carton. And yes we can pack as per your requirement.
A: Can the price be cheaper?
Q: Of course, you will be offered a good discount for a big amount.
A: Why should I choose to buy from you?
Q:Our advantages: 100% quality assurance, develop and manufature follow original ones;Quick response within 24 hours; Small order allowed;Reasonable stock and timely delivery;Neutral packing, customized packing are allowed. Positive customer feedback from abroad market;Excellent after-sales service.
A : Which payment terms can you accept?
Q : Paypal. Western Union, Bank Transfer, T/T...

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