weather, operate air compressor unit for
several minutes afterward to mix water
and battery electrolyte. If water is
needed frequently, check for a cracked
battery case or a faulty voltage regulator
hydrometer. A fully-charged battery should have
a hydrometer indication of 1.237 + 0.062
specific gravity at 800F (260C) electrolyte
To correct hydrometer indications for
temperature variations, add 0.004 to the
hydrometer indication for every 10°F (12
C); that the electrolyte is above 80°F
(26°C); subtract 0.004 for every 10°F
(120C) below 80°F (26°C) electrolyte
d. The indications obtained in all six cells should be
nearly equal. It' any cell is markedly lower, it is
defective. If this low indication is not improved
by charging, the battery should be replaced,
particularly during cold weather.
When charging a weak or sulphated
(brownish color of electrolyte) battery,
the slow charging method must be used.
Never allow electrolyte temperature to
exceed 1 20°F (480C) during charging.
c. Inspect the battery terminals for a tight fit on the
posts and check for corrosion. Remove any
deposits with a wire brush and coat the
terminals, after placing them on the posts, with
technical petrolatum, per Federal Specification
VV-P-236 to prevent further corrosion.
Check the battery case for cracks or leakage.
Engine Fuel Filter Element (Figure 5-5). To
change the engine's fuel filter element, proceed as
a. Using a 13 1mm wrench, unscrew and remove
bolt and gasket attaching filter housing to flange.
b. Using element d-ring, pull element from housing.
Drain fuel and sediment from housing.
Provide adequate ventilation when using
P-D-680, Type II. Avoid prolonged
breathing of vapors and minimize skin
d. Clean housing with a lint free cloth using solvent
per Federal Specification P-D-680, Type 11.
Allow housing to air dry.
e. Clean mating surface of flange. Inspect flange
o-ring. If o-ring is damaged, replace o-ring with a
f. Coat flange o-ring and element gaskets with
g. Install new element over stem in housing with d-
ring in the down position.
h. Assemble housing, with element, to flange using
gasket and bolt.
Figure 5-6. Mechanical Filter