
ENGINE
6-3
(ROUND) Y~~fll^H
CENTRIFUGAL
A ^k
ADVANCE--jflgKpl
MECHANISM
UB|
CAM
KSK^2
LUBRICATOR
VlSMi
REPLACEMENT
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-^ADJUST
SQUARELY
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JUST
TOUCHING
LOBE
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CAM
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HBB
__
I^BH^F
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(SOUARE)
^K^ I /—
CAM
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CAM LUBRICATOR-
REPLACE
WICK
WHEN
NECESSARY
LATERAL
MISALIGNMENT
PROPER
LATERAL ALIGNMENT
Fig.
4- Distributor (V8)
CAUTION: Use extreme care
-when
using tap to
prevent cross threading. Also crank engine sev-
eral times to blow out any material dislodged
during cleaning operation.
7. Install spark plugs with new gaskets and torque to
specifications.
NOTE:
The following are some of the
greatest causes of unsatisfactory spark plug
performance.
•
Installation of plugs with insufficient torque to
fully seat the gasket.
•
Installation of the plugs using excessive torque
which changes gap settings.
•
Installation of plugs on dirty gasket seal.
•
Installation of plugs into corroded spark plug hole
threads.
8^ Connect spark plug wiring.
Service
Ignition System
1.
Remove distributor cap, clean cap and inspect for
cracks, carbon tracks and burned or corroded ter-
minals. Replace cap where necessary.
2.
Clean rotor and inspect for damage or deterioration.
Replace rotor where necessary.
3.
Replace brittle, oil soaked or damaged spark plug
wires.
Install all wires to proper spark plug. Proper
positioning of spark plug wires in supports is impor-
tant to prevent cross-firing.
4.
Tighten all ignition system connections.
5. Replace or repair any wires that are frayed, loose or
damaged.
Us
CORRECT
LATERAL MISALIGNMENT BY
j BENDING
FIXED CONTACT SUPPORT
[NEVER
BEND BREAKER LEVER
Fig.
5 - Point Alignment
Magnetic
Pulse(Breakerless)
Distributor
There are no moving parts in the ignition pulse ampli-
fier, and the distributor shaft and bushings have perma-
nent type lubrication, therefore no periodic maintenance
is required for the magnetic pulse ignition system. Refer
to Section 6Y for an analysis of problems and/or repair
procedures encountered on the Transistorized (Magnetic
Pulse) ignition system.
Standard
(Breaker Point) Distributor
(Figs.
3 or 4)
1.
Check the distributor centrifugal advance mechanism
by turning the distributor rotor in a clockwise direc-
tion as far as possible, then releasing the rotor to
see if the springs return it to its retarded position.
If the rotor does not return readily, the distributor
must be disassembled and the cause of the trouble
corrected.
2.
Check to see that the vacuum spark control operates
freely by turning the movable breaker plate counter-
clockwise to see if the spring returns to its retarded
position. Any stiffness in the operation of the spark
control will affect the ignition timing. Correct any
interference or binding condition noted.
3.
Examine distributor points and clean or replace if
riecessary.
DO
NOT SUCK
IN
TOO MUCH
ELECTROLYTE
TAKE
READING
AT
EYE LEVEL
Fig.
6 - Testing Specific Gravity of Battery
CHEVROtET
CHASSIS SERVICE MANUAL

ENGINE
6-12
ENGINE
MECHANICAL
IN LINE
INDEX
Page
General Description . „ 6-12
Component Replacement and Adjustment 6-12
.Engine Assembly 6-12
Removal 6-12
Installation 6-13
Manifold Assembly 6-14
Removal . 6-14
Installation 6-14
Rocker Arm Cover . 6-14
Removal 6-14
mstallation . . . 6-14
Valve Mechanism
......
1 6-14
Removal 6-14
Installation and Adjustment . 6-14
Valve Lifters
..............
6-15
Locating Noisy Lifters
„.;....
6-15
Removal
.'.*...•
6-15
Installation . 6-15
Valve Stem Oil Seal and/or Valve Spring . 6-16
Replacement . 6-16
Cylinder Head Assembly . 6-16
Removal 6-16
Installation . 6-16
Oil Pan . » 6-17
Removal . . . ; . . 6-17
Installation
.........
. 6-17
Oil Pump . 6-18
Page
Removal . 6-18
Installation . 6-18
Oil Seal (Rear Main) . 6-19
Replacement 6-19
Crankshaft Pulley and Hub 6-19
Removal 6-19
Installation 6-19
Torsional Damper 6-19
Removal 6-19
Installation 6-19
Crankcase Front Cover . 6-20
Removal . 6-20
Installation 6-20
•
Oil Seal (Front Cover) 6-20
Replacement 6-20
Camshaft 6-21
Measuring Lobe Lift . ... .
.-.••.-.
6-21
Removal 6-21
Installation 6-22
Timing Gears
..••••.............••• 6—22
Replacement
6-22
Flywheel
6-22
Removal
* 6-22
Installation
6-22
Engine
Mounts
6-23
Replacement
(Front)
6-23
Replacement
(Rear)
. 6-23
GENERAL DESCRIPTION
The
In
Line engines
(fig. 1L)
covered
in
this section
are
the 1H3 cu. in. L4, the 194,
230
and
250
cu. in. L6,
regardless
of
which passenger vehicle they
are
used
in.
This section covers
the
removal
and
installation
of en-
gine assemblies;
the
removal, installation
and
adjustment
of some sub-assemblies
and
replacement
of
some
com-
ponents.
For
service
to all
components
and
sub-assem-
blies (after removal)
and
removal
of
some sub-assem-
blies,
refer
to
Section
6 of the
Chassis Overhaul Manual.
Because
of the
interchangeability
and
similarity
of
many engine sub-assemblies
and
engine parts, regardless
of which passenger vehicle they
are
used
in,
typical illus-
trations
and
procedures
are
used except where specific
illustrations
or
procedures
are
necessary
to
clarify
the
operation. Although illustrations showing bench opera-
tions
are
used, most single operations, when
not
part
of a
general overhaul, should
be
performed
(if
practical) with
the engine
in the
vehicle.
COMPONENT REPLACEMENT
AND
ADJUSTMENT
ENGINE ASSEMBLY
Removal
1.
Drain cooling system
and
engine
oil.
2.
Remove
air
cleaner
and
disconnect battery cables
at 7.
battery.
3.
Remove hood
as
outlined
in
Section 11.
4.
Remove radiator
and
radiator shroud
as
outlined
in
Section 13.
5.
Remove
fan
blade
and
pulley
as
outlined
in
Section
6K.
6. Disconnect wires
at:
• Starter Solenoid
8.
• Delcotron
9.
Temperature Switch
Oil Pressure Switch
Coil
Disconnect:
Accelerator linkage
at
manifold bellerank.
Exhaust pipe
at
manifold flange.
.
Fuel line (from tank)
at
fuel pump.
Vacuum line
to
power brake unit
at
manifold
(if
so equipped).
• Power steering pump lines
at
pump
end (if so
equipped).
Raise vehicle
and
place
on
jack stands.
Remove propeller shaft.
CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-16
5.
Adjust ignition timing and carburetor idle speed and
mixture.
VALVE STEM OIL SEAL AND/OR VALVE SPRING
Replacement
1.
Remove rocker arm cover as outlined.
2.
Remove spark plug, rocker arm and push rod on the
cylinder(s) to be serviced.
3.
Apply compressed air to the spark plug hole to hold
the valves in place.
NOTE: A tool to apply air to the cylinder is
available through local jobbers or may be manu-
factured. In manufacturing this Tool a AC-46N
Spark Plug or its equivalent is recommended.
This will make the Tool universal for all
Chevrolet engines. Chisel the spark plug as
shown, then drive the porcelain out of the plug
by tapping the center electrode against a hard
block. Using a 3/8" pipe tap, cut threads in the
remaining portion of the spark ^>lug and assem-
ble as shown (fig. 3L).
4.
Using Tool J-5892 to compress the valve spring, re-
move the valve locks, valve cap, valve shield and
valve spring and damper (fig. 4L).
5.
Remove the valve stem oil seal.
6. To replace, set the valve spring and damper, valve
shield and valve cap in place. The close coiled end
of the spring is installed against the cylinder head.
Compress the spring with
Too^
J-5892 and install oil
seal in the lower groove of the stem, making sure the
seal'is flat and not twisted.
NOTE: A light coat of oil on the seal will help
prevent twisting.
7.
Install the valve locks and release the compressor
tool, making sure the locks seat properly in the
upper groove of the valve stem.
NOTE: Grease may be used to hold the locks
in place while releasing the compressor tool.
8. Install spark plug, using a new gasket, and torque to
specifications.
9. Install and adjust valve mechanism as outlined.
CYLINDER HEAD ASSEMBLY
Removal
1.
Remove manifold assembly as. outlined.
2.
Remove valve mechanism as outlined.
3.
Drain cooling system (block).
4.
Remove fuel and vacuum line from retaining clip at
water outlet then disconnect wires from temperature
sending units.
5.
Disconnect upper radiator hose at water outlet hous-
ing and battery ground strap at cylinder head.
6. Remove coil (L6 engines only).
7.
Remove cylinder head bolts, cylinder head and gas-
ket. Place cylinder head on two blocks of wood to
prevent damage.
Installation
CAUTION: The gasket surfaces on both the
head and the block must be clean of any foreign
matter and free of nicks or heavy scratches.
Cylinder bolt threads in the block and threads
on the cylinder head bolt must be cleaned. (Dirt
will affect bolt torque.) Do not use gasket sealer
on composition steel asbestos gasket.
Fig. 3L -
AIF
Adapter Tool
1.
Place the gasket in position over the dowel pins with
the bead up.
2.
Carefully guide cylinder head into place over dowel
pins and gasket.
3.
Coat threads of cylinder head bolts with sealing com-
pound and install finger tight.
4.
Tighten cylinder head bolts a little at a time in the
sequence shown on the torque sequence chart until
the specified torque is reached.
5.
Install coil (if removed).
6. Connect upper radiator hose and engine ground strap.
7.
Connect temperature sending unit wires and install
fuel and vacuum lines in clip at water outlet.
8. Fill cooling system.
•
9. Install manifold assembly as outlined.
10.
Install and adjust valve mechanism as outlined.
Fig.
4L
- Compressing Valve Spring
CHEVROLET CHASSIS SERVICE MANUAL

ENGINE 6-25
refer to Section 6 of the Chassis Overhaul Manual.
Because of the interchangeability and similarity of
many engines, engine sub-assemblies and engine parts,
regardless of which passenger vehicle they are used in,
typical illustrations and procedures are used except
where specific illustrations or procedures are necessary
to clarify the operation. Although illustrations showing
bench operations are used, most single operations, when
not part of a general overhaul, should be performed (if
practical) with the engine in the vehicle.
COMPONENT REPLACEMENT AND ADJUSTMENT
ENGINE ASSEMBLY
Removal
• .1. Drain cooling system and engine oil.
2.
Remove air cleaner and disconnect battery cables at
battery.
3.
Remove hood as outlined in Section 11.
4.
Remove radiator and shroud as outlined in Sec-
tion 13.
5. Remove fan blade and pulley as outlined in Sec-
tion 6K.
6. Disconnect wires at:
• Starter solenoid
• Delcotron
• Temperature switch
• Oil pressure switch
• Coil
7. Disconnect:
• Accelerator linkage at pedal lever.
• Exhaust pipes at manifold flanges.
• Vacuum line to power brake unit at manifold (if
so equipped),
• Power steering pump lines at pump end (if so
equipped).
• Fuel line (from tank) at fuel pump.
• Engine cooler lines (if so equipped).
• Oil pressure gauge line (if so equipped).
8. Raise vehicle and place on jack stands.
9. Remove propeller shaft.
NOTE:
If plug for propeller shaft opening
in transmission is not available, drain
transmission.
10.
Disconnect:
• Shift linkage at transmission.
• Speedometer cable at transmission.
• Transmission cooler lines (if so equipped).
11.
On synchromesh equipped vehicles, disconnect clutch
linkage at cross-shaft then remove cross-shaft en-
gine bracket.
12.
Remove rocker arm covers as outlined, then attach
engine lifting adapter at the proper cylinder head bolt
locations.
13.
Remove front mount bolts.
14.
Attach lifting device and raise engine to take weight
off front mounts, then remove rear mount bolts.
15.
Raise engine to take weight off rear mount, then re-
move crossmember.
NOTE:
On Chevrolets it will be necessary to
remove mount from transmission before cross-
member can be removed.
16.
Remove engine-transmission assembly from vehicle
as a unit.
17.
Remove transmission (and clutch):
Synchromesh Transmission
a. Remove clutch housing cover plate screws.
b.
Remove bolts attaching the clutch housing to en-
gine block then remove transmission and clutch
housing as a unit.
NOTE:
Support the transmission as the last
mounting bolt is removed, and as it is being
pulled away from the engine (to prevent damage
to clutch disc).
c. Remove starter and clutch housing rear cover
plate.
d. Loosen clutch mounting bolts a turn at a time (to
prevent distortion of clutch cover) until the spring
pressure is released. Remove all bolts, clutch
disc and pressure plate assembly.
Automatic
Transmission
a. Lower engine, secured by the hoist, and support
engine on blocks.
b.
Remove starter and converter housing underpan.
c. Remove flywheel-to-converter attaching bolts.
d. Support transmission on blocks.
e. Remove transmission-to-engine mounting bolts.
f. With the hoist attached, remove blocks from the
engine only and slowly guide the engine from the
transmission.
18.
Mount engine in stand.
Installation
1.
Attach lifting device to engine and remove engine
from engine stand.
2.
Install transmission (and clutch):
Synchromesh Transmission
a. Install the clutch on flywheel as outlined in Sec-
tion 7.
b.
Install clutch housing rear cover and starter.
c. Install transmission and clutch housing as out-
lined in Section 7.
d. Install clutch housing cover screws and tighten
securely.
Automatic
Transmissions
a. Position engine adjacent to the transmission and
align the converter with the flywheel.
b.
Bolt transmission to engine, then raise engine and
transmission assembly and install flywheel to
converter attaching bolts.
c. Install converter housing underpan and starter.
3.
Tilt and lower engine and transmission assembly into
the chassis as a unit, guiding engine to align front
mounts with frame supports.
4.
Install front mount bolts and torque to specifications.
5. Raise engine enough to install rear crossmember,
then install crossmember, install rear mount, lower
engine and torque rear mount to specifications.
CHEVROLET CHASSIS SERVICE MANUAL

ENGINE FUEL 6M-5
3.
Disconnect choke rod or choke cable.
4.
Disconnect accelerator linkage.
5.
If equipped with Automatic transmission, discon-
nect TV linkage.
6. Remove carburetor attaching nuts and/or bolts and
remove carburetor.
Test Before Installation -
It is good shop practice to fill the carburetor bowl
before installing the carburetor. This reduces the strain
on the starting motor and battery and reduces the pos-
sibility of backfiring while attempting to start the engine.
A fuel pump clamped to the bench, a small supply of fuel
and the necessary fittings enable the carburetor to be
filled1 and the operation of the float and'intake needle and
seat to be checked. Operate the throttle several times
and check the discharge from the pump jets before in-
stalling the carburetor.
Installation
1.
Be certain throttle body and intake manifold sealing
surfaces are clean.
2.
Install new carburetor to manifold flange gasket (if
required).
3.
Install carburetor over manifold studs.
4.
Start vacuum and fuel lines at carburetor.
5.
Install attaching nuts and/or bolts and tighten
securely.
6. Tighten fuel and vacuum lines.
7.
Connect and adjust accelerator and TV linkage.
8. Connect choke tube or choke rod.
9. Adjust idle speed and mixture, then install air
cleaner. #
Fuel Filter Maintenance
1.
Disconnect fuel line connection at inlet fuel filter
nut.
2.
Remove inlet fuel filter nut from carburetor with a
1"
box wrench or socket.
3.
Remove filter element and spring (fig. 4c).
Fig. 5C-Choke Coil-L6 Engine
4.
Fig. 4C-Fuel Filter
Check element for restriction by blowing on cone
end, element should allow air to pass freely.
5.
Clean element by washing in solvent and blowing out.
Blow in opposite direction of fuel flow.
NOTE: Element should be replaced if plugged
or if flooding ocpurs. A plugged filter will
result in a loss of engine power or rough (pul-
sating) engine feel, especially at high engine
speeds.
6. Install element spring, then install element in car-
buretor so small section of cone faces out.
7.
Install new gasket on inlet fitting nut then install
nut in carburetor and tighten securely.
8. Install fuel line and tighten connector.
Choke Coil Replacement
L6 Engines (Fig. 5c)
1.
Remove air cleaner then disconnect choke rod upper
clip.
2.
Remove bolts attaching choke coil to manifold, then
remove choke coil and choke rod as an assembly.
3.
Disconnect choke rod from choke coil.
4.
Connect choke rod to new choke coil and install as-
sembly on manifold.
5.
Install bolts and tighten securely.
6. Adjust and connect choke rod as outlined.
7.
Start and warm-up the engine then check operation
of choke and install air cleaner.
V8 Engines (Fig. 6c)
1.
Remove air cleaner then disconnect choke rod upper
clip.
2.
Remove choke coil as follows:
WITH ROCHESTER 2GV CARBURETOR
• Remove the choke coil shield by prying with a
screw driver in the cut out provided then re-
move the choke rod.
CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-7
CHARGING SYSTEM
INDEX
Page
General Description . 6Y-7
Maintenance and Adjustments 6Y-9
Static Checks . 6Y-10
System Condition Check and Voltage
•Regular Adjustment. 6Y-10
General Output 6Y-11
Generator Diode and Field Test 6Y-12
Indicator Lamp-Initial Field Excitation
Circuit Tests . 6Y-12
Page
Field Circuit Resistance Wire Tests 6Y-13
Field Relay Test and Adjustment 6Y-14
Other Harness Checks 6Y-14
Service Operations 6Y-14
Generator 6Y-14
Removal and Installation 6Y-14
Pulley Replacement. 6Y-14
Brush Replacement (6" Delcotron). 6Y-15
Double Contact Regulator . . . . . . 6Y-16
GENERAL DESCRIPTION
The charging system includes the battery, generator,
regulator, telltale light, and necessary wiring to connect
these components. The Delcotron is offered as standard
equipment, although there are various capacities avail-
able on all models.
The Delcotron continuous output A.C. generator (fig.
lc) consists of two major parts, a stator and a rotor. The
stator is composed of a large number of windings as-
sembled on the inside of a laminated core that is attached
to the generator frame. The rotor revolves within the
stator on bearings located in each end frame. Two
brushes are required to carry current through the two
slip rings to the field coils wound concentric with the
shaft of the rotor. Six rectifier diodes are mounted in the
slip ring end frame and are joined to the stator windings
at three internally located terminals.
Diodes are mounted in heat sinks to provide adequate
heat dissipation. The six diodes replace the separately
mounted rectifier as used in other types of application.
The diodes change the Delcotron A.C. current to D.C.
current.
Two regulators (fig. 2c) are available on the 1967 vehi-
cles,
a double contact two unit type and a transistor
regulator. The function of these regulators in the charg-
ing system is to limit the generator voltage to a pre-set
value by controlling the generator field current. Both
regulators have an internal field relay unit. The relay
unit allows the telltale lamp to light (as a bulb check)
with the ignition key on and engine not running. When the
engine is started and the generator begins to charge, the
indicator light goes out indicating that the system is op-
erating normally.
The double contact regulator, when used with the
special 63 amp air conditioning model generator (4 ohm
field coil) uses a field discharge diode internally in the
field circuit (figs. 3c and 4c). The added diode adapts the
BRUSH AND
TERMINAL
ASSEMBLY
SLIP RINGS
SLIP RING
END FRAME
_\
THRU
BOLT
DRIVE END
FRAME
BEARING
BEARING
DIODES
ROTOR
5.5" SERIES ID DELCOTRON
STATOR
ASSEMBLY
GREASE
RESERVOIR
BRUSH
FAN ASSEMBLY
6.2" SERIES 2D TYPE 150 DELCOTRON
Fig.
lc—Delcotron Cross-section View
CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-14
VOLTMETER
WIRING HARNESS
CONNECTOR
Fig.
12c—Field Relay Closing Voltage Test
FIELD RELAY CHECKS AND ADJUSTMENT
To check for a faulty relay proceed as follows:
1.
Connect a voltmeter into the system at the regulator
No.
2 terminal to ground (fig. lie).
2.
Operate the engine at fast idle (1500 to 2000 rpm) and
observe voltmeter reading.
3.
If voltmeter shows zero voltage at regulator, check
circuit between No. 2 terminal on regulator to "R"
terminal on Delcotron.
4.
If voltage at regulator exceeds closing voltage
Fig.
13c—Adjusting Field Relay Closing Voltage
specification and light remains on, regulator field
relay is faulty (Refer to specifications). Check and
adjust regulator as follows:
CLOSING VOLTAGE ADJUSTMENT
•1.
Make connections as shown in Figure 12c using a 50
ohm variable resistor.
NOTE: This gives us a variable resistance in
series from a hot lead to the relay coil.
2.
Turn resistor to "open" position.
3.
Turn ignition switch off.
4.
Slowly decrease resistance and note closing voltage
of the relay. Adjust by bending heel iron in the man-
ner illustrated in Figure 13c.
OTHER HARNESS CHECKS
Other wires in the charging system harness need be
checked for continuity by use of an ohmmeter or a test
ligjit (12 Volt). Connect the test so the wire in question is
in series in the test circuit.
SERVICE OPERATIONS
Service Procedures described in this section are for
the 5.5" aluminum and 6.2" perforated stator Delcotrons
(fig. 14c). Where important differences are encountered
separate mention will be made of the two generators.
GENERATOR
REMOVAL AND INSTALLATION
1.
Disconnect the battery ground strap at battery to
prevent damaging diodes.
2.
Disconnect wiring leads at Delcotron.
3.
Remove generator brace bolt, (if power steering
equipped, loosen pump brace and mount nuts) then
detach drive belt (belts).
4.
Support the generator and remove generator mount
bolt (6.2" Delcotron uses 2 mount bolts) and remove
from vehicle.
5.
Reverse the removal procedure to install then adjust
drive belt.
PULLEY REPLACEMENT
5.5" Delcotron
Single Groove Pulley
1.
Place 15/16" box wrench on retaining nut and insert
a 5/16" alien wrench into shaft to hold shaft while
removing nut (fig. 15c).
2.
Remove washer and slide pulley from shaft.
3.
Reverse Steps 1 and
2
to install, use a torque wrench
with a crow-foot adapter (instead of box wrench) and
torque the nut to 50 ft. lbs. (fig. 16c).
Double Groove Pulley
1.
Place a 15/16" socket (with wrench flats on the drive
CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-18
IGNITION SYSTEMS
INDEX
Page
General Description . 6Y-18
Maintenance and Adjustments 6Y-19
Breaker Point System 6Y-19
Breakerless System . . 6Y-X9
Ignition Coil Check 6Y-19
Spark Plugs 6Y-19
Service Operations , 6Y-19
Distributor Contact Points . 6Y-19
Cleaning 6Y-19
Replacement 6Y-20
Setting Dwell Angle 6Y-21
Distributor Condenser 6Y-22
Performance Diagnosis. 6Y-22
Replacement . . 6Y-23
Distributor
Breaker Point Type 6Y-23
Removal. . 6Y-23
Disassembly • 6Y-23
Page
Cleaning and Inspection .....'.., 6Y-25
Assembly . 6Y-25
Installation 6Y-26
Breakerless i 6Y-27
Removal . 6Y-27
Disassembly and Assembly 6Y-27
Installation 6Y-27
Off-Engine Test. . 6Y-27
Coil Replacement 6Y-27
Pulse Amplifier. 6Y-28
Disassembly .6Y-4S8
Component Checks
!
6Y-28
Assembly 6Y-29
Ignition Switch Replacement 6Y-29
Spark Plugs 6Y-30
Cleaning and Regapping I ....... 6Y-30
Installation . 6Y-31
GENERAL DESCRIPTION
There are two ignition systems available on 1967
vehicles. The breaker point type which is continued as
the regular production system and the optional (Corvette
only) transistor controlled breakerless ignition system
(magnetic pulse type). The transistor ignition system
features a specially designed distributor, control unit
(ignition pulse amplifier), and a special coil. Two resist-
ance wires are also used in the circuit; one as a ballast
between the coil negative terminal and ground, while the
other resistance wire provides a voltage drop for the
engine run circuit and is by-passed at cranking. The
other units in the system (the ignition switch, spark
plugs,
and battery) are of standard design. The dis-
tributor and control unit (ignition pulse amplifier) are
shown in Figures li and 2i.
CAP-
VACUUM
PICK-UP
COIL LEADS
PICK-UP COIL
CONNECTOR BODY
Although the external appearance of the distributor
resembles a standard distributor, the internal construc-
tion is quite different. As shown in the exploded view
(fig. 16i) an iron timer core replaces the conventional
breaker cam. The timer core has the same number of
equally-spaced projections, or vanes as engine cylinders.
The timer core rotates inside a magnetic pickup as-
sembly, which replaces the conventional breaker plate,
contact point set, and condenser assembly. The magnetic
pickup assembly consists of a ceramic permanent mag-
net, a pole piece, and a pickup coil. The pole piece
is.
a
steel plate having equally spaced internal teeth, one tooth
for each cylinder of the engine.
The magnetic pickup assembly is mounted over the
main bearing of the distributor housing, and is made to
rotate by the vacuum control unit, thus providing vacuum
advance. The timer core is made to rotate about the shaft
by conventional advance weights, thus providing centrifu-
gal advance.
Fig.
li—
Magnetic Pulse Distributor
Fig.
2i-lgnition Pulse Amplifier Unit
CHEVROLET CHASSIS SERVICE MANUAL