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Comprehensive Guide to Repairing the Steel Lift Ram on a Bobcat 753G Skid Steer Loader
#1
Introduction to the Bobcat 753G Lift Ram Repair
The lift ram (hydraulic cylinder) on the Bobcat 753G skid steer loader is a critical component that enables lifting and lowering the loader arms effectively. Over time, lift rams can develop leaks, lose pressure, or suffer from seal and bushing wear, compromising machine performance and safety. Repairing the steel lift ram involves disassembling the cylinder, replacing worn seals and bushings, and careful reassembly to restore reliable hydraulic function.
This guide provides detailed step-by-step insights into the repair process, including causes of failure, tools and materials needed, practical tips, maintenance advice, and examples from field experiences to help operators and technicians perform successful repairs.

Understanding the Function and Common Issues of Bobcat 753G Lift Rams
  • The lift ram is a double-acting hydraulic cylinder that extends and retracts pistons to raise and lower the loader arms.
  • Common issues include hydraulic fluid leaks caused by worn internal seals (packing), damaged wiper seals, bent or scratched pistons and rods, and worn bushings that lead to play and reduced control.
  • Leaks can lead to loss of pressure, slow or uneven lift movement, and contamination ingress causing accelerated wear.

Tools and Materials Needed for Lift Ram Repair
  • Hydraulic cylinder seal kit specifically designed for Bobcat 753/753G models
  • Standard hand tools including wrenches, sockets, and screwdrivers
  • Special pullers or pin drivers for removing the ram from the loader
  • Clean containers for hydraulic fluid draining and parts soaking
  • Cleaning solvents and lint-free cloths
  • Grease and hydraulic fluid recommended by Bobcat OEM guidelines
  • Safety gear: gloves, eye protection, and shop rags

Step-by-Step Procedure for Lift Ram Seal and Bushing Replacement
  1. Safety and Preparation:
    • Park the machine on level ground, turn off the engine, and relieve hydraulic pressure by cycling the lift controls with the engine off.
    • Support the loader arms securely to prevent sudden drops.
  2. Remove Lift Ram from Loader:
    • Disconnect hydraulic lines carefully, catching fluid in a reservoir or container.
    • Remove mounting pins or bolts securing the lift ram to loader arms using proper pin drivers or tools.
  3. Drain Hydraulic Fluid and Clean Ram:
    • Drain residual fluid from the ram and clean the exterior to prevent contaminants entering during disassembly.
  4. Disassemble the Cylinder:
    • Remove retaining nuts securing the cylinder heads, often requiring pipe wrenches or specialized tools to avoid damage.
    • Extract the piston rod assembly by carefully sliding out, avoiding damage to the rod and seals.
    • Remove all old seals, wiper rings, and bushings from the head and piston.
  5. Inspect Cylinder Components:
    • Check the piston rod for scratches, bends, or corrosion.
    • Inspect the cylinder barrel for scoring or dents.
    • Examine bushings for wear—they should be snug with minimal play.
    • Replace damaged components as necessary.
  6. Install New Seals and Bushings:
    • Use the seal kit to replace all internal seals, including rod packing, piston seals, and wiper seals.
    • Lubricate seals before installation to prevent damage and ease assembly.
    • Press in new bushings ensuring correct fit and alignment.
  7. Reassemble Cylinder:
    • Carefully reinsert the piston rod and assembly into the cylinder barrel.
    • Torque retaining nuts to manufacturer specifications to ensure proper seal compression.
    • Make sure all components are seated accurately to avoid leaks.
  8. Reinstall Lift Ram:
    • Attach lift ram to loader arms with pins or bolts, securing them firmly.
    • Reconnect hydraulic lines, checking for any leaks or damage.
    • Refill hydraulic system with appropriate fluid and bleed air from the system through controlled lift cycles.
  9. Test Operation:
    • Operate loader arms through full range to check for smoothness, leaks, and proper pressure holding.
    • Monitor for any unusual noises or slow response.

Tips and Best Practices for Successful Repair
  • Use OEM or high-quality aftermarket seal kits tailored for Bobcat 753/753G to ensure proper fit and durability.
  • Take photos during disassembly for reference during reassembly, especially noting seal positioning and orientation.
  • Cleanliness is critical; thoroughly clean all parts and keep the work area free of dirt to avoid contamination.
  • When removing stubborn nuts or components, use penetrating oil and heat cautiously to prevent damage.
  • Lubricate all seals and surfaces with compatible grease or oil to facilitate assembly and initial operation.
  • After reinstallation, monitor hydraulic fluid levels and maintain a slow start-up procedure to prevent sudden pressure spikes.

Maintenance Recommendations to Extend Lift Ram Life
  • Regularly inspect the lift ram and hydraulic lines for leaks, cracks, or corrosion.
  • Follow Bobcat’s hydraulic fluid change intervals and maintain fluid cleanliness through filter replacements.
  • Avoid overloading the loader beyond rated capacities to reduce stress on hydraulic components.
  • Perform periodic lubrication of pivot pins and bushings to minimize wear.
  • Address small leaks early before they cause larger seal damage or hydraulic contamination.

Real-World Experiences and Practical Insights
  • One Bobcat 753G operator reported that replacing the lift ram seals and bushings with a comprehensive OEM kit resolved persistent fluid seepage and restored smooth loader arm control. Proper cleaning and careful seal installation prevented premature seal failures.
  • In another case, attempts to save time by only replacing external seals led to repeated leaks; a full internal seal and bushing overhaul proved necessary for lasting repair.
  • Use of pipe wrenches and ratchet straps to stabilize the cylinder during reassembly helped technicians avoid damage and ease nut tightening.
  • Experienced mechanics emphasize the importance of correctly orienting smaller inner seals beneath main sealing rings to avoid leaks and early failures.

Terminology Explained
  • Lift Ram (Lift Cylinder): The hydraulic cylinder responsible for raising and lowering the loader arms.
  • Seals and Packings: Components that prevent hydraulic fluid from leaking out of the cylinder and protect internal components from contamination.
  • Wiper Ring: A seal that cleans the piston rod as it moves in and out, preventing dirt entry.
  • Bushing: A bearing sleeve that reduces friction and wear between the piston rod and cylinder head.
  • Torque Specification: The manufacturer-prescribed force used to tighten fasteners, ensuring proper sealing and mechanical integrity.
  • Bleeding: The process of removing air from the hydraulic system after repairs or fluid changes.

Summary
Repairing the steel lift ram on a Bobcat 753G involves thorough disassembly, inspection, and replacement of internal seals, wiper rings, and bushings to restore hydraulic integrity and machine performance. Following precise procedures, using quality parts, and maintaining cleanliness are essential for a durable and leak-free repair.
Proper removal and reinstallation of the lift ram, careful attention to seal orientation, and subsequent system bleeding ensure smooth operation and prolonged component life. Regular preventive maintenance complements these efforts by reducing wear and preempting hydraulic failures.
Drawing on practical experiences and detailed repair steps, this guide equips technicians and operators with the knowledge to confidently address lift ram issues on Bobcat 753G skid steers, improving reliability and operational efficiency.
If specific parts, torque values, or technical diagrams are needed, consulting official Bobcat service manuals or authorized parts suppliers is highly recommended for safety and accuracy.
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Comprehensive Guide to Repairing the Steel Lift Ram on a Bobcat 753G Skid Steer Loader - by MikePhua - Yesterday, 04:04 PM

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