Sender: <marv@lancaironline.net> (Marvin Kaye)
To: lml
Date: Thu, 30 May 2002 16:30:03 -0400
Message-ID: <redirect-1252098@logan.com>
From: Sky2high@aol.com
Subject: Re: [LML] Lancair 320 nose strut
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Welcome.

If you suspect oil is leaking from the strut, then you should contact Lancair 
about how or who could replace the seals.

If you want to "service" the strut, the only way is to replace the strut oil, 
usually 20W motorcycle fork oil.  The procedure follows:

1. Neutralize the weight on the nose by placing weights on the horizontal 
stabilizer with a support under the tail cone to keep the tail from hitting 
the ground.  Use enough weight so that it is easy to move the tail up and 
down and the nose wheel only has to reach full extension.

2.  Allow the Nitrogen to escape the thru the Schrader valve and, using a 
bicycle valve stem removal tool, carefully remove the stem.

3.  Attach a 2 to 3 foot clear vinyl hose to the valve and allow the nose to 
fully depress the strut - you will probably get little or no old and ugly 
fluid out of the strut, this is ok.

4.  Fill a cup with the fork oil and immerse the tube end in the oil.  Move 
the nose of the plane up and down until there is no more air in the tube or 
until you feel confident that you have exchanged the old oil with some new 
and overfilled the strut.  You may repeat this step a few times to get 
cleaner fluid in the strut.  Finally, allow the nose to settle - the strut to 
become fully depressed, remove the hose and replace the valve stem.  Tighten 
it snugly, but do not over tighten.

5.  Slowly introduce nitrogen into the Schrader valve until the strut is 
exrtended.

6.  Remove the weight from the tail and pull down on the nose.  You will be 
looking for about 3 inches between the top of the flange and the bottom of 
the strut, perhaps 2.75 inches if you have the newer thicker flange.  
Usually, the pressure is too great and the strut will remain fully extended.  
I suggest you use a pin punch and a light hammer to tap the valve end which 
will result in short pffts of gas.  If you try to push something on the 
valve, by hand, I guarantee that you will eventually release too much gas and 
have to go back to step 5.  After each release of gas, pull down on the nose 
and remeasure.

Good Luck!

Scott Krueger
LNC2 - N92EX, modern self-centering strut.