JLG 450A series II - User Manual

Questions and Answers

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wigginsanthonyAug 3, 2025
How to fix slow shifting in JLG 450A II Lifting Systems?
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  Jessica BowmanAug 3, 2025
  Slow shifting or a complete failure to shift in JLG Lifting Systems can be caused by obstructed or restricted flow through the servo control signal lines. Ensure these lines are clear and that the signal pressure is sufficient to shift the motor. Also, check the control orifices in the motor; if they are obstructed or the wrong size, this can increase shift times. Clean or replace the orifices as needed, ensuring the proper ones are installed.
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warren39Aug 13, 2025
Why are my JLG 450A II Lifting Systems making excessive noise and vibration?
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  francisryanAug 13, 2025
  Excessive noise and vibration in JLG Lifting Systems can stem from several causes: * Insufficient hydraulic fluid, leading to cavitation. * Air trapped in system lines or the motor, also causing cavitation. * A loose or incorrect shaft coupling producing vibrations. * Misaligned shafts creating frictional vibration. * Hydraulic oil viscosity exceeding acceptable limits, resulting in cavitation. To resolve this, ensure the hydraulic fluid reservoir is at the correct level, the oil supply to the motor is adequate and unobstructed, system lines and components are purged of air, the correct shaft coupling is properly fitted, shafts are correctly aligned, and the hydraulic oil is the appropriate fluid for the operating conditions.
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kevinstaffordAug 21, 2025
What to do if JLG 450A II Lifting Systems are operating hot?
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  obutlerAug 22, 2025
  If your JLG Lifting Systems are running hot, it could be due to a few reasons. First, check the hydraulic fluid level, as an insufficient amount won't meet the system's cooling demands; fill the reservoir to the proper level. Secondly, the heat exchanger might be failing or obstructed, hindering its ability to cool the system; ensure the heat exchanger receives adequate airflow and is in good operating condition, repairing or replacing it if necessary. Lastly, a system relief valve that's unseated for too long or fails can cause overheating; repair or replace any malfunctioning relief valves and verify the loads on the machine aren't excessive.