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Two weeks ago I had a hydraulics leak, looked under the hood and the hydraulics cap ring was unsteated. I finger tightened, reload the oil and mowed for another 4 hours. Then another 4 the next day. Las Saturday, 15 minutes into the mow, I lost hydraulics, thinking the seal broke again.

What did I do wrong?

See pictures




Is this an easy fix after removing broken stem?
What would cause this type of break? Not tight enough?