Dry cleaning solvent, P-D-680 or P-S661, used to clean
the engine base (serial nos. L-1666-T through L-1668-
parts is potentially dangerous to personnel and property.
Use in a well-ventilated area as the fumes are
(3) Remove the oil tube by unscrewing the
dangerous if inhaled. Avoid repeated and prolonged
two tube nuts securing the tube to the street tee (19) and
skin contact. Do not use near open flame or excessive
the governor. Lift out the tube.
heat. Flash point of solvent is 100F. -138F. (38C. -
(4) Unscrew the street tee from the engine
b. Cleaning, Inspection and Repair. Clean the
the street tee (3).
valve cover gasket surface on the engine block. Wash
the covers, washers, and hardware in solvent. Inspect
the threads for damage. Replace all damaged parts and
install new gaskets.
Dry cleaning solvent, P-D-680 or P-
c. Tappet adjustment.
S661, used the clean parts is potentially
(1) Turn the crankshaft over by hand until the
dangerous to personnel and property.
lifter (6, fig. 4-38) that is to be adjusted is at its lowest
Use in a well-ventilated area as the
fumes are dangerous if inhaled. Avoid
(2) On serial nos. L-1475-T through L-1478-T
repeated and prolonged skin contact.
units, insert a 0, 012 inch (. 0305cm) feeler gage (5)
Do not use near open flame or
between the valve stem (8) and lifter screw (7). On
excessive heat. Flash point of solvent
serial nos. L-1666-T through L-1668-T units, insert a 0.
is 100F. -138F. (38C. -59C. ).
008 inch (. 0203cm) feeler gage for the two intake
b. Cleaning, Inspection and Repair. Clean all the
valves and a 0. 016 inch (. 0406cm) feeler gage for the
two exhaust valves.
parts in a cleaning solvent. Inspect the lines for cracks
i. Installation. Reverse the removal procedures.
or evidence of leakage. Check the fittings and tube nuts
for damaged threads. Replace all damaged parts.
c. Reassembly and Installation.
disassembly and removal procedure.
a. Valve cover, removal and disassembly.
(2) Remove the throttle rod (25).
(4) Remove the cotter pin (10) securing the
choke rod (11) to the carburetor choke lever (13) and
slide the rod from the choke lever.
washers (3) and washers (4) securing the intake
manifold and carburetor (16) to the block (26) and
remove the intake manifold carburetor assembly, and
manifold. Support the exhaust system
before removing the intake manifold.
35) and lock washers (4) securing the carburetor (9) and
gasket (12) to the intake manifold (1).
(7) Remove the adapter (8) from the
carburetor and the pipe plug (13) from the manifold.
support pin (6), and the valve covers (3) and gaskets (4)
Figure 4-37. Valve cover and gasket.
from the engine block.