sure to cut holes properly. Blank gaskets can cause
serious damage.
the lubricant being sealed. Lubricate the lips of lip- type
1. Seals.
seals before installation with the same type of lubricant in
(1 ) Duo-cone floating seals. Floating ring seals have
which the seal will be operating. If during installation, the
highly finished surfaces and are held together by toric
seal lips must pass over a shaft that has splines, a
sealing rings. The flexibility of the toric sealing rings
keyway, rough surface, or a sharp edge, the lip can be
makes the floating sealing rings self- alining and
easily damaged. Shim stock or other material can be
compensates for wear on the metal surfaces. During
formed to provide a smooth surface over which to slide
disassembly, tape the metal floating seal rings together
the seal.
so they will be kept in matched sets. Always install the
m. Hydraulic Systems.
metal floating ring seals in pairs; that is, two new seals
(1) Cleanliness. When removing components of a
together, or two seals that have previously run together.
hydraulic system, cover all openings in both the
Never reinstall used toric sealing ring. Handle all parts
component and the machine. If evidence of metal or
with care to avoid nicks. File smooth any part, other than
rubber particles are 'found in the hydraulic system, flush
the sealing faces, that have nicks that may make
the entire system. Disassemble and reassemble
reassembly difficult or questionable. Wash used parts.
hydraulic components on a clean surface. Clean all parts
Use a wire brush to clean dirt or rust from the bore of the
in a non-flammable cleaning fluid. Then lubricate all
seal retainers to assure they are clean and smooth.
components to aid in reassembly. Inspect all sealing
Remove all oil or protective coating from floating seals
components (o - rings, gaskets, etc.) when
and retainers with a non-flammable cleaning solvent.
disassembling and reassembling hydraulic components.
Check the ramps for tool marks and nicks. On used
Install new components if necessary. Use only
parts, remove dirt or rust deposits from the ramps.
components listed in the repair parts list, one seal may
Smooth the surface with emery cloth. Be sure the ramp
resemble another but will not necessarily be compatible
on the retainers and the floating seals are dry. Before
in a given installation.
assembling floating ring seals together, wipe faces of
(2) Hydraulic lines. When installing metal tubes,
seals with lint-free tissue to remove any foreign material
tighten all bolts finger-tight. Then, in this order, tighten
or fingerprints. Place one drop of oil on the cleaning
the bolts at the rigid end, the adjustable end, and the
surface and coat the sealing surfaces of the seals. Be
mounting brackets. After the tubes are mounted, install
careful to prevent any oil from contacting the toric sealing
the hoses. Connect both ends of hoses with all bolts
ring or its mating surface. Install new toric sealing rings
finger-tight. Due to manufacturing methods there is a
or floating ring seals. Seat the toric sealing ring uniformly
natural curvature to a hydraulic hose. Install the hose so
in the relief of the ring seal. Be sure the toric sealing ring
any bend is in this curvature. In case of replacement
is not twisted. It must set straight against the lip which
hoses with angled-stem and reusable fittings, the hose
keeps it from falling off the floating ring seal. If an
curvature must be taken into consideration when
installer tool is not used, install the toric sealing ring and
assembling and positioning angled stems. Position the
floating ring seal as an assembly by pressing on the toric
hose so it does not rub the machine or another hose and
sealing ring. Use finger pressure only. Be sure the toric
has a minimum of bending and twisting. Tighten hoses in
sealing ring is seated uniformly in the recess of both the
place. After hoses are installed, follow this procedure,
floating ring and the retainer. Make sure it sets in the
with engine running, move the appropriate levers to
bore straight and against the lip that keeps it from falling
move the hydraulic operated components to every
possible position. Observe the hoses during the cycle.
out of the retainer. DO NOT USE A SCREWDRIVER OR
Stop the engine, relieve the pressures, and eliminate any
STICK TO ASSEMBLE TORIC SEALING RING IN THE
twisting, rubbing, or excessive drooping of hoses by
RETAINER.
rotating the stem of the hose.
(2) Lip-type seals.Generally, the toe or spring-
n. Painting. Refer to TM 9-213 for painting
loaded lip on an OIL SEAL FACES the oil being sealed
instructions for the crane.
or the oil having the higher pressure. The toe or lip of a
o. Tire Maintenance. Refer to TM 9-1870-1 for
GREASE SEAL FACES AWAY from
instructions for care and maintenance of pneumatic tires.
2-4
