Fault Phenomenon: Skyjack SJ8841 telescopic boom aerial work platform hydraulic tank cap is missing, allowing water and dust to enter the tank.

Troubleshooting Process:
– Checked on-site: cap fell off.
– Checked threads: threads damaged.
– Checked chain: chain broken.
– Checked human cause: accidentally lost.

Root Cause: The tank cap retaining chain broke or the threads were damaged, causing it to be lost.

Required Parts: Hydraulic tank cap assembly.