Danny, sounds like you have a blockage. (possibly at the gear door valve). You could install plugs at the cylinders that are working and test and troubleshoot again. Most likely something is restricting flow to or from the the suspect cylinder as the fluid just moves the piston back and forth so a blockage on either side will cause the gear to not move . You could also remove the gear down side line from the suspect cylinder and retest. If the gear goes up, you know the problem is on the low pressure return line and if the gear still won't go up, you know there is a problem on the high pressure side line feeding the cylinder. I would also check the fittings on the suspect cylinder for blockage as well. It is also possible there is something wrong in the cylinder itself making it much harder to move which would explain why the others move and the suspect cylinder moves only with some coaxing.
After thinking about this and writing the above, I would remove the suspect cylinder and verify it moves freely like it should and there are no blockages on the fittings. It is also possible you inadvertently pinched an o ring making it more stiff to move than the other 2. When I rebuilt my system, there are very sharp edges on the grooves that can easily cut and pinch o rings if you don't round them off with emery cloth...
Fwiw. Randy Snarr N694RS
Sent from my iPad My main gear actuators were leaking so I overhauled them. This isn’t a big deal and I’ve done this numerous times on spam cans with no problems. Upon reinstallation I found two situations; the left main wouldn’t respond at all; the inboard and nose wheel doors wouldn’t stay closed. Since this is a closed system and I could see signs of leakage on at least one gear door actuator, I figured before messing with the gear I better rebuild the gear door actuators too. I did that, reassembled everything, and ran leak checks after cleaning the previous leak mess. Now, this situation remains…sort of. After several gear cycles, the left main wouldn’t break the over center down lock. I decided to tap it with a rubber mallet to break it loose just to see what happens. At that point the pump kicks on and the wheel goes up but the doors still bleed down and open after less than a minute. I now have probably a dozen or so gear cycles and, although the left main is now responding, it’s the last to do so but only after what must be called a burp in the system. By that, I mean the other two legs go up, the pump stops momentarily and then kicks back on to take the last leg up. But, the doors still bleed down and come open in less than a minute. I can't see any visible leaks so this tells me there must be an internal leak someplace. The question is where? Can the sequencing valves cause this or is it the emergency extension ball valve or something else? And how do you check these items for internal leakage? Any suggestions would be appreciated. Thanks in advance, Danny LNC2-360, 550 hours N 38° 43' 25.7" W 77° 30' 38.6"
|