Jeep UNIVERSAL CJ-2A - Page 21

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plug hole with compressed air. If compressed air
is not available, start the engine and accelerate to
1000 rpm. to blow out the carbon and dirt. Stop
the engine.
c. Remove the plugs carefully with a spark plug
wrench.
d. Inspect the plugs for serviceability. Especially
check for burned and eroded electrodes, blistering
of porcelain at the firing tip, cracked porcelain, or
black deposits and fouling. These conditions in-
dicate that the plugs have not been operating at
the correct temperature. See Par. I-14. Replace
bad or worn plugs in sets.
e. Measure the electrode gap of each plug with a
wire gauge as shown in Fig. 21. Adjust each elec-
trode gap to the specific gap by bending the
outer electrode mounted in the plug shell.
f. Reinstall plugs. Torque with a wrench to proper
setting.
FIG. 21-SETTING SPARK PLUG GAP
C-4. Torque Cylinder Head and Manifold
Torque the cylinder head bolts with a torque
wrench to 60 to 70 lb-ft. [8,3 a 9,7 kg-m.]. Follow
the sequence shown in Fig. 22 or Fig. 23. On F4-134
engines, do not overlook tightening the cylinder
head bolt, No. 5, in the intake manifold directly
under the carburetor opening.
Torque all manifold attaching nuts evenly to
30 to 35 Ib-ft. [4,1 a 4,8 kg-m.].
20
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FIG. 22-F4-134 ENGINE CYLINDER HEAD
BOLT TIGHTENING SEQUENCE
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FIG. 23-L4-134 ENGINE CYLINDER HEAD
BOLT TIGHTENING SEQUENCE
C-5. Clean Crankcase Ventilator
On engines equipped with a closed crankcase
ventilating system, remove the control valve and
tubes and clean them thoroughly. Inspect the oil
filler
tube cap gasket and replace if defective.
C-6. Service Manifold Heat Control Valve
On L4-134 engines equipped with a manifold heat
control valve, test the valve for free operation.
Place a few drops of penetrating oil at each end of
the shaft where it passes through the manifold.
Then move the valve up and down a few times
to work the oil into the bushing.
C-7. Check Compression
Take compression readings with a compression
gauge, as shown in Fig. 24, at each cylinder while
cranking the engine with the starter motor. Allow
only four compression strokes at each cylinder and
record only the first and fourth readings. Interpret
the readings as follows:
FIG. 24--COMPRESSION AND VACUUM GAUGE