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Take a close look. The envelope has discolored from..... oil. The label inside the package has discolored and become shiny from.... oil. I wiped the bolts on the paper towel and found.... oil residue

Preservative oil...so they don't rust on an warehouse shelf before an unknown future sale date.




Per the U.S. DOT/FAA AC 43.13-1B/2A Sept 98 edition
Acceptable Methods, Techniques, and Practices
Aircraft Inspection, Repair & Alteration
(yes, it may be a version or two old)
Page 7-6, Section 7-40.b
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Be sure the bolt and nut threads are clean and dry, unless otherwise specified by the manufacturer.



So, every time you fly on an airliner...that is how the fasteners holding the aircraft together are tightened.



This is what I worked on today at work...

[Linked Image]


The bolt holding the blades on failed in flight. I did not assemble this, but it was done with a new bolt, and a torque driver. Looking at it after the failure, it was obvious there was lubricant on the threads inside the rotor head.

1989 Mitsubishi Montero SWB 0.0L (3.5L soon?) Auto, Front LSD, Rear SR Locker, Aisin hubs, Safari Snorkel, ARB Front Bumper, Warn M8000, Bushwacker Flares
1984 Mitsubishi Montero
2005 Dodge SRT-4
1970 Plymouth 'Cuda (in pieces)
...and a few others less interesting.