Chevrolet Light Duty Truck 1973, Руководство по обслуживанию

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6 Y -4 2 EN G INE ELECTRICAL
Fig. 2 2 i —A d v a n c e W e ig h ts In s ta lle d
and crank engine until No. 1 intake valve closes
and continue to crank slowly about 1/3 turn
until timing mark on pulley lines up with timing
tab.
2. Position distributor to opening in block in normal
installed attitude, noting position of vacuum control
unit.
NOTE: On Mark IV engines the distributor
may be installed with the distributor cap in
place by using the punch mark on the
distributor drive gear for alignment instead
of the rotor as follows: Align the punch mark
on the gear, which represents the centerline
of the rotor, approximately 2° clockwise from
the distributor cap # 1 terminal, then rotate
the distributor body counterclockwise slightly
(1/8 turn) so that the distributor points just
break open (.002 maximum). Secure the
distributor clamp and proceed with steps 3
thru 7 as required.
3. Position rotor to point toward front of engine (with
distributor housing held in installed attitude), then
turn rotor counter-clockwise approximately 1/8 turn
more toward left cylinder bank and push distributor
down to engine camshaft. It may be necessary to
rotate rotor slightly until camshaft engagement is
felt.
4. While pressing firmly down on distributor housing,
kick starter over a few times to make sure oil pump
shaft is engaged. Install hold-down clamp and bolt
and snug up bolt.
5. Turn distributor body slightly until points just open
and tighten distributor clamp bolt.
6. Place distributor cap in position and check to see
that rotor lines up with terminal for No. 1 spark
plug.
7. Install cap, check all high tension wire connections
Fig. 2 3 i — Six C y lin d e r E n g in e D is tr ib u to r In s ta lla tio n
and connect spark plug wires if they have been
removed.
8. Connect vacuum line to distributor and distributor
primary wire to coil terminal.
9. Start engine and set timing as described under
Tune Up in Section 6.
Distributor Off-Engine Test
The distributor’s centrifugal and vacuum advance can be
checked in a distributor testing machine or synchroscope
designed to accommodate the distributor. However, since
this involves removing the distributor from the engine,
this test may be postponed until other system checks
have been made.
Coil Replacement
1. Disconnect ignition switch and distributor leads
from terminals on coil.
2. Pull high tension wire from center terminal of coil.
3. Remove the two coil support mounting bolts or
loosen friction clamp screw and remove coil.
4.
Place new coil in position and install attaching bolts
or tighten clamp screw.
5.
Place high tension lead securely in center terminal
of coil and connect ignition switch and distributor
primary leads to terminals on coil.
6. Start engine and check coil operation.
Spark Plug and Wire Service
Removal and Inspection
1. To disconnect wires, pull only on the boot. Pulling
on the wire might cause separation of the core of
the wire. Remove spark plugs and gaskets using a
5 /8 "
deep socket on the
5 / 8 "
hex tapered plugs.
Use care in this operation to avoid cracking spark
plug insulators.
2. Carefully inspect the insulator and electrodes of all
LIGHT DUTY TRUCK SERVICE MANUAL