Gear problem

[travis]

Bill,

I have this problem chronically when the aircraft sits for a while with a low (not full) hydraulic quantity. It’s always on the first retraction cycle after a few days of sitting. I have a pair of gear door actuators that weep a little while they sit. I believe this is causing the system to lose its prime. When the gear is cycled up there are certain positions on the sequencing valve that will time out if there’s not enough pressure. I believe this is what’s happening in my case and resetting the selector resets the timer and allows the pumps to finish priming the system and complete the cycle. This annual I plan to rebuild the actuators, but in the mean time the key is to top off the hyd quantity periodically. Also with my system I don’t need to cycle the gear, just take the gear lever to the idle position for a five count then back to the up position and the cycle will complete!

_travis

[Skymaster337B]

I've been having the same problem, gear goes up, no amber light, gear doors stay open in the air. But everything works ok when jacked up in the hangar. I put new switches on the up locks and power pack, checked tire pressure, checked fluid levels, and serviced nose gear strut; but still nothing worked.

I finally put new springs on the main gear uplock pushrods, and I'm happy to report all is good. However, good luck finding a new spring. It seems Cessna doesn't make them anymore, and I got the last one in the system.

There's plenty of used springs available, but good luck using them since you already have a used one installed. The new spring was a full 1.5" longer than the old worn out one.

Enjoy,

Rob

[hharney]

The new spring is longer? Does that make sense, wouldn't the old one be weak and stretched?

[Skymaster337B]

The old spring is shorter because it was under constant compression for the last 40 years.