Spent 8 hours chasing a phantom hydraulic leak on a King Air 200 that turned out to be a $2 O-ring on the reservoir cap vent line.

It was one of those days where the logbook just said 'hydraulic fluid low, check and service.' Topped it off, ran the system, saw a few drips near the belly. Figured it was a line or a fitting, right? Pulled panels, cleaned everything, used dye, the whole nine yards. Couldn't pin it down. Pressure checks were fine on the ground. My partner finally noticed a tiny, almost invisible mist coming from the vent line on the reservoir itself when the pumps cycled. The O-ring on the vent fitting was just hard and flat. Swapped it, leak gone. Eight hours of my life for a part that costs less than a coffee. Ever have a job where the fix was stupid simple but finding it was a marathon?

2 comments

2 Comments

wyatt7711mo ago

My old shop swore by dye, but @wright.drew's safety wire story changed that.

wright.drew1mo ago

Oh man, that's the worst. I once spent a whole shift looking for an electrical short that was killing a nav light. Traced wires, pulled bundles, the works. My forehead was actually sore from wearing a headlamp. The fix? A single stray piece of safety wire from a previous job was just barely touching a terminal. Felt like a genius and an idiot at the same time.

-1