Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Bobcat 763G Won’t Move but Hydraulics Work Normally
#1
The 763G and Its Control System Design
The Bobcat 763G skid steer loader was part of Bobcat’s G-series lineup, introduced in the late 1990s and early 2000s. These machines were built with a focus on operator safety, simplified diagnostics, and hydraulic efficiency. The 763G featured a 46-horsepower Kubota diesel engine, hydrostatic drive, and a control system that relied on interlocks and solenoids to manage movement and hydraulic functions.
Unlike earlier models, the G-series phased out seat switches and instead relied on a combination of safety bar position, traction lock solenoids, and controller feedback to determine whether the machine could move. This system was designed to prevent unintended motion, but it also introduced new failure points that could immobilize the loader even when the engine and hydraulics were functioning normally.
Symptoms of a Locked Traction System
A common issue with the 763G is when the machine starts, the bucket and tilt functions operate normally, but the loader won’t move. It behaves as if the parking brake is engaged, even though the safety bar is lowered and the green traction button is pressed. In this condition:
  • The traction lock light flashes briefly
  • The machine beeps intermittently
  • The solenoid may not activate audibly
  • The loader remains stationary despite throttle input
This behavior typically indicates a fault in the traction lock system, which prevents the drive motors from engaging. The system includes a dual-coil solenoid—one coil for “pull” activation and another for “hold”—as well as a relay, fuse, and controller logic.
Diagnosing the Fault Code
When the traction light flashes, the machine is signaling a fault. Instead of shutting down, operators can press and hold the headlight button to display the fault code on the hour meter. This code helps pinpoint the issue, whether it’s a failed solenoid, bad relay, or wiring damage.
In one case, the traction light flashed six times, accompanied by beeping. This pointed to a traction lock fault, likely caused by a failed solenoid or disrupted power supply. The solenoid may have lost its “hold” signal from the controller, or the relay may have failed to deliver “pull” voltage.
Common Causes and Quick Checks
Several components should be inspected:
  • Parking brake fuse: Check for continuity and proper amperage
  • Parking brake relay: Swap with a known good relay from the fuse panel
  • Traction lock solenoid: Test for resistance and audible activation
  • Wiring harness: Inspect for rodent damage, especially near the cab and under the seat
  • Safety bar switch: Ensure full engagement and clean contacts
Rodent damage is surprisingly common in stored machines. Mice and squirrels often chew through insulation, causing intermittent faults. One operator discovered chewed wires near the controller after his machine sat idle for several months.
Emergency Movement and Cab Access
If the machine must be moved urgently, the cab can be raised and the parking brake components manually disengaged. This allows the loader to roll freely, but it should only be done with caution. The cab is secured by two ½-inch nuts at the front corners. Once removed, the cab tilts forward, exposing the hydraulic and electrical systems.
Operators should be aware that disabling the parking brake removes a critical safety feature. The machine can roll unexpectedly, especially on slopes or uneven terrain. Use wheel chocks and have a spotter present during emergency moves.
Fuel Pickup Issues and Related Repairs
Some 763G units also suffer from broken fuel pickup tubes, causing the engine to run only when the tank is nearly full. This issue is unrelated to the traction lock but often discovered during troubleshooting. The repair involves:
  • Replacing the pickup hose
  • Installing a new screen and grommet
  • Securing with clamps
  • Total cost: approximately $25
  • Time required: under one hour
This fix is straightforward and can be done while the cab is raised for traction lock inspection.
Recommendations for Long-Term Reliability
To prevent future immobilization:
  • Keep the machine stored in rodent-resistant conditions
  • Perform monthly checks on fuses and relays
  • Clean and lubricate safety bar contacts
  • Use dielectric grease on solenoid connectors
  • Document fault codes and repair history for reference
Fleet managers should train operators on fault code retrieval and basic electrical diagnostics. A flashing traction light is not just a nuisance—it’s a diagnostic gateway.
Conclusion
The Bobcat 763G is a reliable and capable skid steer, but its traction lock system can immobilize the machine if any component fails. By understanding the dual-coil solenoid design, fault code retrieval, and emergency override procedures, operators can restore mobility and avoid costly downtime. Whether clearing snow or grading driveways, the 763G proves that even small machines require smart troubleshooting to keep moving.
Reply


Possibly Related Threads…
Thread Author Replies Views Last Post
  Troubleshooting Bobcat 430 Skid Steer Issues MikePhua 0 1 Today, 12:58 AM
Last Post: MikePhua
  What Should Be Replaced While the Engine Is Out of a Bobcat 753G MikePhua 0 2 10-11-2025, 07:38 PM
Last Post: MikePhua
  Bobcat 323 Mini Excavator Hydraulic Function Troubleshooting MikePhua 0 7 10-11-2025, 06:41 PM
Last Post: MikePhua
  Bobcat 753 G 2003 Oil Pressure Warning Light Troubleshooting MikePhua 0 5 10-11-2025, 06:09 PM
Last Post: MikePhua
  CAT D4G Dozer Engine Runs but Will Not Move MikePhua 0 1 10-11-2025, 05:57 PM
Last Post: MikePhua
  Electrical Faults in the Bobcat 430 Mini Excavator MikePhua 0 4 10-11-2025, 05:49 PM
Last Post: MikePhua
  Bobcat 763 G Won't Start: Troubleshooting Electrical Issues MikePhua 0 10 10-10-2025, 04:33 PM
Last Post: MikePhua
  Diagnosing Fuel Solenoid Voltage Issues on the Bobcat 763 MikePhua 0 12 10-10-2025, 04:29 PM
Last Post: MikePhua
  Overheating Issues on the Bobcat 873 Skid Steer MikePhua 0 11 10-10-2025, 03:39 PM
Last Post: MikePhua
  T-190 One Side Won’t Move MikePhua 0 23 10-05-2025, 06:40 PM
Last Post: MikePhua
  Auxiliary Hydraulics Setup and Troubleshooting in Compact Equipment MikePhua 0 30 10-05-2025, 04:16 PM
Last Post: MikePhua
  Bobcat S130 Charging System Diagnosis and Repair MikePhua 0 28 10-05-2025, 04:15 PM
Last Post: MikePhua
  How Do I Set Up Hydraulics for a Thumb on a CAT 325C MikePhua 0 26 10-05-2025, 04:12 PM
Last Post: MikePhua
  Replacing Tracks on a Bobcat Skid Steer Loader MikePhua 0 35 10-03-2025, 07:39 PM
Last Post: MikePhua
  Addressing Oil and Fluid Leaks in Bobcat 873 Skid Steer MikePhua 0 42 10-02-2025, 12:53 PM
Last Post: MikePhua

Forum Jump:


Users browsing this thread: 1 Guest(s)