REPAIR OF ENGINE
Section I. I N T R O D U C T I O N
the use of direct support and general support personnel
in this section and
responsible for maintenance of the engine.
succeeding sections of this chapter are published for
Section II. E N G I N E
(3) Turn engine until two setscrews securing ar-
6-2. GENERAL. The four-cycle engine
is so termed
mature to fan assembly are visible. Loosen the two
because of the four distinct and separate strokes of the
s e t s c r e w s . Remove four capscrews attaching the
piston during one complete power cycle. The engine
generator housing to the fan housing (fig 6-1). Separate
develops power by rapidly burning a highly compressed
the fan housing and generator housing.
mixture of fuel and air in a closed combustion chamber.
(4) Turn engine until two setscrews are visible
The ignited force of the burned fuel-air mixture is
directed against the piston that compressed the gas,
through the hole in the left side of the fan housing.
Loosen the two setscrews and remove the fan assembly
driving the piston away from the ignition. The piston is
from the engine crankshaft.
a t t a c h e d to a crankshaft, which changes the re-
(5) Remove four capscrews and washers attaching
ciprocating motion of the piston to a rotary, driving
fan housing to the engine and remove fan housing.
motion. The four operations intake, compression,
(6) Remove four bolts, nuts, washers, rubber shock
power, and exhaust, each require a complete stroke.
mounts and cup washers attaching engine support bars
This gives one power stroke per cylinder for each two
to the rail. Remove engine.
revolutions of the crankshaft.
c. Cleaning and Inspection.
ENGINE AND GENERATOR-WELDER DIS-
(1) Clean the engine with an approved cleaning
solvent and dry thoroughly. Be sure all dirt, grease, grit
a General. Whenever it becomes necessary to
and other foreign matter are removed (app D).
remove the engine and generator-welder assembly
(2) Clean all mounting hardware with an ap-
from its mounting in the shop set for repair purposes,
proved cleaning solvent. Inspect each threaded surface
the engine and generator-welder assembly is removed
for corrosion or damage. Replace all mounting hard-
ware that is corroded or damaged.
d. Installation. Install the assembly in reverse order