An excavator operator is performing fine grading with a tilt bucket. They notice that the bucket frequently drifts out of the set position, requiring constant adjustments, even when the machine is static. What is the most likely cause?

Question: An excavator operator is performing fine grading with a tilt bucket. They notice that the bucket frequently drifts out of the set position, requiring constant adjustments, even when the machine is static. What is the most likely cause?

Answer options:

• A worn swing motor
• Excessive backlash in the bucket linkage ✅ Internal leakage within the tilt cylinder or its control valve
• Insufficient hydraulic pump flow

Correct answer: Internal leakage within the tilt cylinder or its control valve

Explanation: Drift in a hydraulic attachment like a tilt bucket, especially when static, is a classic symptom of internal leakage. This leakage can occur past the piston seals within the tilt cylinder or through a faulty internal seal in the control valve directed to that cylinder. A worn swing motor or excessive backlash in the bucket linkage would cause different symptoms (e.g., uncontrolled swing or loose bucket movement during operation), and insufficient pump flow would affect dynamic operations across multiple functions, not just static drift.