MAINTENANCE
ITEMS
MAINTENANCE ITEM #31 - Newsletter
#59
(by Lee Beery)
Recently, during our aircraft annual, I disassembled, cleaned and inspected
the nose gear assembly. I then replaced the 0-rings (2) and installed a new
oil seal. (See Maintenance Item #23.) I then installed the correct amount of
hydraulic oil and reinstalled the assembly. Then I added the bearings
lubricating oil (I use chain saw “bar” lube). Before I reinstalled the
screw in the bearing lubrication port of the outer cylinder, I removed the
nose gear support. With the aircraft weight now on all three gears, I pulled
down and pushed up on the propeller to cycle the nose gear to achieve maximum
travel. When I did this, I could hear rushing in and out of the lubrication
port.
I explained all of this to Max Bishop and we think we may now know what it is
so hard to keep that lubrication oil in the gear assemblies. When the aircraft
becomes airborne, the springs extend the gears, increasing the air capacity of
the assembly. The easy route for the air to enter is past the oil seal. When
the aircraft lands, the air in the cylinder is compressed and with oil sitting
on top of the oil seal when the air is forced out past the oil seal, it takes
some oil with it.
This is just a theory but I am in the process of testing this theory and will
report my findings in future newsletters.