bbbair

I have recently acquired an AC that has Spring Air Retracts, the plane has been sitting dormant for over five years so I was leary about the state of the hardware...

I pressurized the tanks to 90 PSI and hit the switch - right on cue they popped into the wing.

Then; I toggled the swith to drop the gear ... they released and sort of half dropped out of the wing...[] So I excercised them for the next half hour with limited results. [:@]

Does anyone have any suggestions as to how to improve the opening of this landing gear?? []

JohnBuckner

My Feedback: (1)

I have been using #105's in a P-38 for pylon racing and these use a newer a lever actuated valve. Also am finishing up a second one for my caller to race using the same gear but older and taken out of a 38 quite a few years older, this type uses the older push and hold valve.

I had similar syptoms on the old gear but found the older valve sticky and a drop of oil on the push button cured the problem. If the servo arm does not push and hold the valve open with enough force then air will bleed back in and try to stop the gear from lowering. I also cleaned the cylinder push rods and lubed with a tiny drop of oil. These rods can get severely gummed up. I love this gear.

John

Carlos Murphy

My Feedback: (72)

"Refrigeration oil" is the most common lub used for retracts, ATF should work just as well or even "Marvel Mystery OIL".
I'm sure the "O"rings in the cylinders are dry after setting for so long.

bbbair

OK - a drop of lubrication seems to be the way to go.

One of my buddies has suggested "White Lithium Grease" - this stuff is (in his opinion) a lubricant that will not harm the O rings. Apparently the O rings are a special type of rubber/neoprene/ plastic (?) that is sensitive to certain oils...

Comments?

TLH101

My Feedback: (90)

Why not call or E-mail the guys that make them.
http://www.retracts.com/

Richard L.

My Feedback: (24)

You could go with Parket Super O-Lube, which is especially made for O rings and won't clog air lines: [link]http://www.bvmjets.com/Accessories/superlube.htm[/link]

bbbair

Thanks Guys!!

bbbair

OK I emailed the guys at Air Spring and they said;

"The O rings are a buna type rubber. We only lubricate them with baby oil, a small amount."

Now for my confession... [:@]
I originally tested these retracts in my workshop with the plane resting in it's cradle...inverted. [:@]

For all of you who missed that - the key word is; inverted...The air pushed the gear up into the wings (down) with no problems, once the air was bled off the springs were not strong enough to overcome the weight of the LG and wheels when inverted. Once I turned the plane upright the retracts worked EVERY TIME! ...

Now that's one for the giggle files ...

britbrat

That's OK Bruce -- it was fun watching