Air Leak Question..
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Ok, I have a simple air up/air down system. BV Retract Valve. Air up to 100 psi Gear Down very slow leak. Gear Up leak is much faster. I have checked all T's and connections I can get to. Should I suspect the air cylinders? I swapped out retract valves same story.
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You could easily just plug air directly into one side of each cylinder, and watch for a leak. Thats what I usually do before I install them. There should be zero leakage. Keep the items in the hookup down to a minimum. I have a small Robart hand pump that works great for this - its a small volume of air, and it will let you know very quickly if there is a leak or not.
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I would suspect one of the retract units myself. Easy way to check the retract unit is pull it out of the plane air it up and dunk it in a pan of water. Have you tried putting some oil in the system sometimes that will fix minor leaks.
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ORIGINAL: aaflyer
Ok, I have a simple air up/air down system. BV Retract Valve. Air up to 100 psi Gear Down very slow leak. Gear Up leak is much faster. I have checked all T's and connections I can get to. Should I suspect the air cylinders? I swapped out retract valves same story.
Ok, I have a simple air up/air down system. BV Retract Valve. Air up to 100 psi Gear Down very slow leak. Gear Up leak is much faster. I have checked all T's and connections I can get to. Should I suspect the air cylinders? I swapped out retract valves same story.
You might find a quiet place and air the system up to around 120 psi and maybe you will get lucky and hear the leak too. This occasionally works if the leak is fast. Wiggle the struts ... some times the leak is only evident when they are moved a certain way.
It is a good suggestion to check all the cylinders before installation and the robart hand pump is one of the most used tools in my shop.
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Found the problem(s) Up line had leak at one of the mains and down line had small leak at the nose cylinder. Thanks to all
Found the problem(s) Up line had leak at one of the mains and down line had small leak at the nose cylinder. Thanks to all
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I've gone through this pain a few times, I always test my air system - up and down - before closing everything up. If I lose more than 10 psi in 8 hours or so, I start chasing leaks. No plastic T's, wire wrap (not tie wraps) on airline/nipple joints, add thin lube to all air cylinders and excercise them a bit, and use liquid Teflon to seal all the screw-in air fittings before mounting the retracts and air cylinders...no leaks (knock wood) in the last 4-5 years since doing this.
Barry
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Hi Barry,
Could you please inform me about: "liquid teflon"?
I´m going to install missing nipples on the retracts of my SM L-39 Albatros, and was looking for some stuff to smear on before screwing them in, to secure tightness.
Pete
Could you please inform me about: "liquid teflon"?
I´m going to install missing nipples on the retracts of my SM L-39 Albatros, and was looking for some stuff to smear on before screwing them in, to secure tightness.
Pete
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Anybody know how to get air lines off brass nipples (connections to cylinders/tee's/restrictors) without sliting them and creating a scratch on the nipple? The newer type air lines like BV sells are very robust and I have a heck of a time getting them off without cutting them. The resulting scratch will frequently leak air when I reconnect the line. The problem is compounded when the connection is difficult to reach inside the plane.
I mention this because sometimes when I am trouble shooting leaks, I create additional problems by disconnecting and reconnecting air lines.
Craig
I mention this because sometimes when I am trouble shooting leaks, I create additional problems by disconnecting and reconnecting air lines.
Craig
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Anybody know how to get air lines off brass nipples (connections to cylinders/tee's/restrictors) without sliting them and creating a scratch on the nipple? The newer type air lines like BV sells are very robust and I have a heck of a time getting them off without cutting them. The resulting scratch will frequently leak air when I reconnect the line. The problem is compounded when the connection is difficult to reach inside the plane.
I mention this because sometimes when I am trouble shooting leaks, I create additional problems by disconnecting and reconnecting air lines.
Craig
Anybody know how to get air lines off brass nipples (connections to cylinders/tee's/restrictors) without sliting them and creating a scratch on the nipple? The newer type air lines like BV sells are very robust and I have a heck of a time getting them off without cutting them. The resulting scratch will frequently leak air when I reconnect the line. The problem is compounded when the connection is difficult to reach inside the plane.
I mention this because sometimes when I am trouble shooting leaks, I create additional problems by disconnecting and reconnecting air lines.
Craig
I have a small butane fired iron from Weller that heats up in less than a minute and I use it a ton. it also converts into a small pencil torch. One of those great little tools I use all the time.
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ORIGINAL: petera38
Hi Barry,
Could you please inform me about: "liquid teflon"?
I´m going to install missing nipples on the retracts of my SM L-39 Albatros, and was looking for some stuff to smear on before screwing them in, to secure tightness.
Pete
Hi Barry,
Could you please inform me about: "liquid teflon"?
I´m going to install missing nipples on the retracts of my SM L-39 Albatros, and was looking for some stuff to smear on before screwing them in, to secure tightness.
Pete
Apply sparingly with a toothpick and make sure you apply all around the threaded area of the nipple, re-install and lightly tighten (it's easy to strip out the threads on thin aluminum cylinders). I've had Skymaster, Robart, Jet Legend, and some unknown aiy cylinders leak until doing this.
As Keith S mentioned earlier, if the nipples don't want to come out, I apply heat with a soldering iron, it will loosen the epoxy or other (usually none) sealant used during manufacture. Ditto with removing old/hardened air line from nipples - just heat them up or melt off.
I have a set of very small ignition and jeweler's wrenches to remove and tighten fittings, but on really small ones, I uses some small, flat/wide nose pliers, being careful not to grab or mar the nipple part of the fitting.
Barry