actual removal procedures to prevent contamination to
the fitting to leak; or excessive torque. If a leak appears
the opened system.
in the swivel nut area, check that the swivel nut is
properly torqued. If necessary, disconnect fitting and
CONTAMINATION CONTROL PROCE-
check for contamination or damage. If the leak persists
DURES.--Perform contamination control procedures
after cleaning, and the swivel nut is properly torqued,
before removing any hose or hose assemblies. You
replace the hose assembly.
should use approved solvents and clean, lint-free cloths
to clean the affected area and wipe down fittings to
Checking For Wear and Deterioration
remove excessive contaminants. Use a suitable
container to catch spilled fluid. Have replacement hose,
Check hose and hose assemblies for signs of wear
hose assemblies, or protective closures on hand for
and deterioration. Replace any hose or hose assembly
installation when you disconnect hose or hose
when a chafe guard appears worn or shows signs of
assemblies. If hose replacement is not practical, cap or
cracking; when a firesleeve is worn through, torn, cut,
plug hose or hose assembly ends immediately after
or oil soaked; when hose or hose assembly has weather
disconnecting.
protective coatings or sleevings that are worn, cracked,
or torn, thus exposing the hose or hose assemblies to
REMOVAL PROCEDURES.--Once contamina-
corrosion.
tion control has been accomplished, you can begin
removal of hose and hose assemblies. Remove all
Checking Hose or Hose Assembly Installations
supporting clamps from hose or hose assembly.
Remove lockwire (if present) from swivel nuts. Turn
Check hose or hose assembly installations
swivel nuts only to disconnect hose assembly. Loosen
carefully. Proper routing and clamping in accordance
nuts carefully to avoid damage. Disconnect the hose
with applicable MIM is mandatory. If retaining wires
assembly by using two open-end wrenches. One is to
on swivel nuts are backed out, replace the hose
grip and prevent turning of the fitting to which the hose
assembly. Look for kinks or twists. Observe lay line, if
assembly is connected, and the other is to loosen the
possible. A kinked hose or hose assembly must be
swivel nut.
replaced. A twisted hose or hose assembly may be
Hose and hose assemblies (particularly Teflon)
relieved by loosening clamps and swivel nuts, and then
have a tendency to become set to shape in service.
straightening the hose by hand. Retorque the swivel
Some Teflon hose assemblies are deliberately
nuts and tighten the clamps. A preformed hose, or hose
preformed during the fabrication process. Do not
assembly, may have a smaller bend radius. Do not
attempt to straighten a preformed hose. Protect the
attempt to straighten preformed hose or hose
preformed areas from distortion by a restrainer. The
assemblies. Excessive bends or signs of chafing may be
restrainer may be of wire, metal, plastic forms, or any
due to loose, oversize, or worn clamps. Replace
other suitable device to retain the preformed
oversized or worn clamps, and tighten the clamp
configuration. Install the protective closures to seal
without squeezing the hose.
open parts of hydraulic lines and ends of removed hose
or hose assemblies.
Checking Clamps
Installing Hose Assemblies
You should check the clamps to make sure they are
the correct type and size, that the position of the hose is
When you install hose or hose assemblies, it is
correct within the clamp, and that the cushion material
important that you follow certain practices or
is positioned correctly. Reposition hose and clamps as
procedures to prevent premature failure of hose or hose
needed. Cushion material should NOT lodge between
assembly or possible injury. Before you begin actual
end tabs of a closed clamp. Do NOT use clamps with
installation procedures, there are guidelines you should
fuel-resistant cushioning unnecessarily, as this type of
remember about installing hose or hose assemblies.
cushioning material deteriorates rapidly when exposed
The replacement hose or hose assembly must be a
to air.
duplicate of the one removed in length, outside
diameter, material, type, contour, and associated
Removing Hose Assemblies
markings.
Hose or hose assembly removal procedures must
Only fluid conforming to MIL-H-5606,
include contamination control procedures as well as
MIL-H-83282, or MIL-H-81019 is to be used on
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