b. Hold the housing toward a strong light source
and inspect the cylinder bore for pitting, scratches and
e. Inspect spring for cracks or permanent set
visible wear pattern. If any of these defects are present,
and replace if damaged.
replace entire assembly.
Always replace cups (11 & 12) if piston (10)
c. Using a hone, remove any dirt not removed
has been removed.
during the cleaning process. A hone may be used to clean
g. Inspect threads on screws, fittings and filler
the cylinder bore if done with extreme care.
cap. Replace if damaged.
bore diameter of the cylinder to a new assembly. The
a. Lubricate all parts with hydraulic fluid.
difference between the two should be no greater than
b. Replace gaskets (15 and 17, fig. 7-2) and
install fitting (16) and screw (14).
(2) An alternate method is to install the piston
c. Install spring (13) into housing (18).
(10, fig. 7-2) into the housing (18) and check clearance
Position new cups (11 and 12) on piston (10) and install
using a wire feeler gage. If clearance exceeds 0.007
piston. Install washer (9) and retainer (8)
inch replace entire assembly.
d. Place boot () over end of housing (18) and
install link (6).
Insure that no burrs remain if a housing has
e. Install gasket (5), filler cap (4), gasket (3)
been honed. Remove any burrs with a debur-
and screw (2). Install pipe plugs (1).
ring tool if necessary. If burr are not
If the master cylinder assembly is not to be
removed, damage to the cylinder cups (11 &
12, fig 7-2) and fluid leakage will result.
d. Insure that intake and bypas ports (located be-
tween housing bore and housing reservoir) are clean
Refer to TM 5-3810-295-12 for installation procedures.
and free of restrictions. Use a soft copper wire not
larger than 0.020-inch diameter to probe and clean
Section III. REPAIR OF CRANE HEATER AND LINES
Removal and Disassembly
c. Refer to figure 7-3 and remove lines,
a. Disconnect the electrical lead.
clamps and attaching parts required. Refer to figure 7-4
b. Drain the heater of engine coolant at drain valve
and remove components of the heater assembly as
(10, fig. 7-3).
required for repair or replacement.