ENGINE 6-14
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 through bolts and torque to
specifications.
5.
Raise engine enough to install rear crossmember,
then install crossmember, install rear mount, lower
engine and torque bolts to specifications.
6. Remove lifting device and lifting adapter then install
rocker arm cover as outlined.
7.
On synchromesh equipped vehicles, install clutch
cross shaft engine bracket, then adjust and connect
clutch as outlined in Section 7.
8. Connect:
• Speedometer cable.
• Shift linkage at transmission.
9; Install propeller shaft.
10.
Remove jack stands and lower vehicle.
11.
Connect:
Power steering pump lines (if disconnected).
Vacuum line to power brake unit (if disconnected).
Fuel line at fuel pump.
Exhaust pipe at manifold flange.
Accelerator linkage at manifold bellcrank.
12.
Connect wires at:
Coil
Oil pressure switch
Temperature switch
Delcotron
Starter solenoid
13.
Install pulley, fan blade and fan belt as outlined in
Section 6K.
14.
Install radiator and shroud as outlined in Section 13.
15.
Install and adjust hood as outlined in Section 11.
16.
Connect battery cables.
17.
Fill with coolant, engine oil and transmission oil,
then start engine and check for leaks.
18.
Perform necessary adjustments and install air
cleaner.
MANIFOLD ASSEMBLY
Removal
1.
Remove air cleaner.
2.
Disconnect both throttle rods at bellcrank and re-
move throttle return spring.
3.
Disconnect fuel and vacuum lines at carburetor.
Disconnect choke cable on \A engines.
4.
Disconnect crankcase ventilation hose at rocker arm
cover.
5.
Disconnect exhaust pipe at manifold flange and dis-
card packing.
6. Remove manifold attaching bolts and clamps then
remove manifold assembly and discard gaskets.
7.
Check for cracks in manifold castings.
8. If necessary to replace either intake or exhaust
manifolds, separate them by removing one bolt and
two nuts at center of assembly. Reassemble mani-
folds using a new gasket. Tighten finger tight and
torque to specifications after assembly to cylinder
head. Transfer all necessary parts.
Installation
1.
Clean gasket surfaces on cylinder head and
manifolds*
2.
Position new gasket over manifold end studs on head
and carefully install the manifold in position making
sure the gaskets are in place.
3.
Install bolts and clamps while holding manifold in
place with hand.
4.
Torque bolts to specifications.
NOTE: On L6 engines center bolt and end bolt
torque differ.
5.
Connect exhaust pipe to manifold using a new
packing.
6. Connect crankcase ventilation hose at rocker arm
cover.
7.
Connect fuel and vacuum lines at carburetor.
8. On L4 engines connect choke cable and adjust as out-
lines in Section 6M.
9. Connect throttle rods at bellcrank and install throttle
return spring.
10.
Install air cleaner, start engine, check for leaks and
adjust carburetor idle speed and mixture.
ROCKER ARM COVER
Removal
1.
Disconnect crankcase ventilation hose(s) at rocker
arm cover.
2.
Remove air cleaner.
3.
Disconnect temperature wire from rocker arm cover
clips.
4.
Remove rocker arm cover. '
CAUTION: Do Not pry rocker arm cover loose
Gaskets adhering to cylinder head and rocker
arm cover may be sheared by bumping end of
rocker arm cover rearward with palm of hand or
a rubber mallet.
Installation
1.
Clean gasket surfaces on cylinder head and rocker
arm cover with degreaser then, using anew gasket,
install rocker arm cover and torque bolts to
specifications.
2.
Connect temperature wire at rocker arm cover clips.
3.
Install air cleaner.
4.
Connect crankcase ventilation hoses.
VALVE MECHANISM
Removal
1.
Remove rocker arm cover as outlined.
2.
Remove rocker arm nuts, rocker arm
balls,
rocker
arms and push rods.
NOTE:
Place rocker arms, rocker arm balls
and push rods in a rack so they may be rein-
stalled in the same location.
Installation and Adjustment
NOTE:
Whenever new rocker arms and/or
rocker arm balls are being installed, coat bear-
ing surfaces of rocker arms and rocker arm
balls with Molykote or its equivalent.
1.
Install push rods,
socket.
Be sure push rods seat in lifter
CHEVROLET CHASSIS SERVICE MANUAL
ENGINE 6-19
OIL SEAL (REAR MAIN)
Replacement
The rear main bearing oil seal can be replaced (both
halves) without removal of the crankshaft.
NOTE:
Always replace the upper and lower
seal as a unit. Install with the lip facing toward
the front of the engine.
1.
With the oil pan removed, remove the rear main
bearing cap.
2.
Remove oil seal from the groove by lifting the end
tab (fig. 7L) then clean seal groove.
3.
Lubricate the lip and O.D. of a new seal with engine
oil. Keep oil off the parting line surface. Insert
seal in cap and roll it into place with finger and
thumb,
using light pressure so beads on seal O.D.
are not cut by seal groove at cap parting line. Be
sure tabs on seal are properly located in cross
grooves.
4.
To remove the upper half of the seal, use a small
hammer to tap a brass pin punch on one end of seal
until it protrudes far enough to be removed with
pliers (fig. 8L).
NOTE:
Always clean crankshaft surface re-
moving all foreign deposits before installing a
new seal. Also clean seal groove.
5. Lubricate the lip and O.D. of a new seal with engine
oil. Keep oil off the parting line surface. Gradually
push with a hammer handle, while turning crank-
shaft, until seal is rolled into place. (Similar to in-
stalling a main bearing.) Be careful that seal bead
on O.D. is not cut. Compress seal towards crank-
shaft as much as possible.
6. Install the rear main bearing cap (with new seal) and
torque to specifications. Be sure cross seal tabs
are in place and properly seated.
CRANKSHAFT PULLEY AND HUB
(Chevy II with L4 Engine)
Removal
1.
Drain radiator and disconnect upper and lower radi-
ator hoses at radiator.
2.
Remove radiator core as outlined in Section 13.
3.
Remove fan belt. Remove crankshaft pulley from
pulley hub.
4.
Install puller Tool J-6978 to pulley hub with two
3/8"
x 2" and one 5/16" x 2" bolts and remove hub
then remove puller tool.
Installation
1.
Coat oil seal contact area on hub with engine oil
position hub over crankshaft and key and start hub
into position with a mallet. Using Tool J-5590 drive
onto crankshaft until it bottoms against crankshaft
gear.
NOTE:
Crankshaft extends slightly through hub
and a tool is necessary to drive hub completely
into bottomed position.
2.
Install pulley onto hub.
NOTE:
There are two 3/8" holes and one
5/16" hole that must be matched on hub in order
Fig.
9L - Removing Torsional Damper
to properly position timing mark.
3.
Install fan belt and adjust using strand tension gauge.
4.
Install radiator as outlined in Section 13.
TORSIONAL DAMPER
Removal
1.
Remove radiator core, as outlined in Section 13.
2.
Remove fan belt and (if so equipped) accessory drive
pulley and belt.
3.
Install Tool J-6978 to damper and turn puller screw
to remove damper (fig. 9L). Remove tool.
Installation
1.
Coat front cover oil seal contact area of damper with
engine oil.
CAUTION: It is necessary to use installer
Tool J-22197 to prevent the inertia weight sec-
Fig.
10L - Installing Torsional Damper
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 6-26
6. Remove lifting device and lifting adapter then install
rocker arm covers as outlined.
7.
On synchromesh equipped vehicles, install clutch
cross-shaft engine bracket, then adjust and connect
clutch as outlined in Section 7.
8. Connect:
• Speedometer cable.
• Shift linkage at transmission.
• Transmission cooler lines (if so equipped).
9. Install propeller shaft.
10.
Remove jack stands and lower vehicle.
11.
Connect: \ '
Power steering pump lines (if so equipped).
Vacuum line to power brake unit (if so equipped).
Exhaust pipes at manifold flanges.
Accelerator linkage at pedal lever.
Fuel line at fuel pump.
Engine cooler lines (if so equipped).
Oil pressure gauge lines (if so equipped).
12.
Connect wires at:
Coil
Oil pressure switch
Temperature switch
Delcotron
Starter solenoid
13.
Install pulley, fan blade and fan belt as outlined in
Section 6K.
14.
Install radiator and shroud as outlined in Section 13.
15.
Install and adjust hood as outlined in Section 11.
16.
Connect battery cables.
17.
Fill with coolant, engine oil and transmission oil,
then start engine and check for leaks.
18.
Perform necessary adjustments and install air
cleaner.
INTAKE MANIFOLD
Removal
1.
Drain radiator and remove air cleaner.
2.
Disconnect:
Battery cables at battery.
Upper radiator and heater hose at manifold.
Accelerator linkage at pedal lever.
Fuel line at carburetor. ;
Wires at temperature sending switch and coil
(both sides).
Power brake hose at carburetor base.
Spark advance hose at distributor.
Crankcase ventilation hoses (as required).
3.
Remove distributor cap and mark rotor position with
chalk. Remove distributor clamp and distributor,
then position distributor cap rearward clear of
manifold.
4.
Remove coil.
5.
Remove manifold-to-head attaching bolts, then re^
move manifold, (with carburetor on) from engine and
discard gaskets and seals.
6. If manifold is to be replaced,,transfer:
Carburetor and carburetor mounting studs.
Temperature sending switch.
Water outlet and thermostat (use new gasket).
Heater hose adapter.
Choke coil.
Installation
1.
Clean gasket and seal surfaces of manifold, cylinder
heads and block.
2.
Install manifold end seals on block as shown (fig.
2V).
3.
Install side gaskets on cylinder heads using sealing
compound around water passages (fig. 2V).
4.
Install manifold bolts, and torque to specifications in
the sequence outlined on the Torque Sequence Chart.
5.
Install coil.
6. Install distributor with the rotor pointing at the chalk
mark, then install distributor cap.
NOTE:
If the crankshaft has been rotated while
the distributor was removed, time distributor to
number 1 cylinder as outlined in Section 6Y.
7.
Connect:
Battery cables at battery.
Upper radiator and heater hose at manifold.
Accelerator linkage at pedal lever.
Fuel line at carburetor.
Wires at temperature sending switch and coil
(both sides)!
Power brake hose at carburetor base.
Spark advance hose at distributor.
Crankcase ventilation hoses (as required).
Fill with coolant, start engine, check for leaks and
adjust timing and carburetor idle speed and mixture.
EXHAUST MANIFOLD
Removal
NOTE:
If equipped with "Air Injection Reactor
System", remove air manifold and tubes as out-
lined in Section 6T.
1.
Disconnect battery ground cable.
-
2.
Disconnect and remove Delcotron (as required).
3.
On 396 and 427 cu. in. engines, remove spark plugs
Fig. 2V - Intake Manifold Gasket and Seal Location
CHEVROLET CHASSIS SERVICE MANUAL
ENGINE 6-32
Fig.
1GV - Removing Oil Seal (Lower Half)
bearing cap, aligning slot on top end of extension
shaft with drive tang on lower end of distributor
drive shaft.
2.
Install pump to rear bearing cap bolt and torque to
specifications.
NOTE:
Installed position of oil pump, screen
is with bottom edge parallel to oil pan rails.
3.
Install oil pan as outlined.
OIL SEAL (REAR MAIN)
Replacement
The rear main bearing oil seal can be replaced (both
halves) without removal of the crankshaft.
Fig.
12V - Removing Torstonal Damper
NOTE:
Always replace the upper and lower
seal as a unit.. Install with the lip facing toward
the front of the engine.
With the oil pan and oil pump removed, remove the
rear main bearing cap.
Remove oil seal from the groove by prying from the
bottom with a small screw driver (fig. 10V).
Lubricate the lip of a new seal with engine oil. Keep
oil off the parting line surface as this is treated with
glue. Insert seal in cap and roll it into place with
finger and thumb, using light pressure so seal tangs
at parting line do not cut bead on back of seal.
To remove the upper half of the seal, use a small
hammer to tap a brass pin punch on one end of seal
until it protrudes far enough to be removed with
pliers (fig. 11V).
NOTE:
Always wipe crankshaft surface clean
before installing a new seal.
1.
2.
3.
5.
Fig.
1IV - Removing Oil Seal (Upper Half)
Lubricate the lip of a new seal with engine oil. Keep
oil off the parting line surface as this is treated with
glue. Gradually push with a. hammer handle, while
turning crankshaft, until seal is rolled into place.
(Similar to installing a main bearing.) Be careful
that seal tangs at parting line do not cut bead on back
of seal.
6. Install the rear main bearing cap (with new seal) and
torque to specifications.
TORSIONAL DAMPER
Removal
1.
Remove fan belt, fan and pulley as outlined in Sec-
tion 6K.
2.
Remove the radiator and shroud as outlined in Sec-
tion 13.
NOTE:
If additional operations such as cam-
shaft removal are not being performed, the radi-
ator will not have to be removed
.on
Chevrolets
and Corvettes equipped with 396 and 427 cu. in.
engines.
. 3. On Corvettes equipped with 427 cu. in. engines, re-
move engine front mount through-bolts and raise
front of engine enough for torsional damper to clear
frame crossmember.
CHEVROLET CHASSIS SERVICE MANUAL
SECTION 6K
ENGINE COOLING
INDEX
Page
General Description . . . 6K-1
Maintenance and Adjustments 6K-1
Coolant Level 6K-1
Coolant System Checks 6K-1
Periodic Maintenance 6K-2
Cleaning 6K-2
Reverse Flushing 6K-2
Radiator 6K-2
Page
Cylinder Block and Cylinder Head 6K-2
Hot Water Heater 6K-2
Fan Belt . 6K-2
Adjustment ....". 6K-2
Thermostat . 6K-2
Replacement 6K-2
Water Pump. . . . 6K-3
Removal 6K-3
Installation 6K-3
GENERAL DESCRIPTION
A pressure cooling system is provided for on all
models by a pressure type radiator cap (fig. 1). The
pressure type radiator cap used is designed to hold a
pressure above atmospheric pressure in the cooling
system. Excessive pressure is relieved by a valve within
the cap that opens to radiator overflow.
The water pump is a ball bearing, centrifugal vane
impeller type. It requires no care other than to make
certain the air vent at the top of the housing and the drain
holes in the bottom do not become plugged with dirt or
grease. Removal and installation of the water pump is
covered in this section. For overhaul procedures of the
water pump refer to Section 6K of the Passenger Chassis
Overhaul Manual.
For radiator, refer to Section 13 of this manual For
radiator shroud, refer to Section 11 of this manual.
Fig.
I—Pressure Radiator Cap
MAINTENANCE AND ADJUSTMENTS
Coolant Level
The radiator coolant level should only be checked when
the engine is cool, particularly on cars equipped with air
conditioning. If the radiator cap is removed from a hot
cooling system, serious personal injury may result
The cooling system fluid level should be maintained
one inch below the bottom of the filler neck of the radia-
tor when cooling system is cold, or at the bottom of the
filler neck when the system is warm. It is very impor-
tant that the correct fluid level be maintained. The seal-
ing ability of the radiator cap is affected when the cooling
level is too high.
All passenger car cooling systems are pressurized
with a pressure cap which permits safe engine operation
at cooling temperatures of
up
to 247°F.
When the radiator cap is removed or loosened, the
system pressure drops to atmospheric, and the heat
which had caused water temperature to be higher than
212°F, will be dissipated by conversion of water to
steam. Inasmuch as the steam may form in the engine
water passages, it will blow coolant out of the radiator
upper hose and top tank, necessitating coolant replace-
ment Engine operating temperatures higher than the
normal boiling point of water are in no way objectionable
so long as the coolant level is satisfactory when the
engine is cooL
Upon repeated coolant loss, the pressure radiator cap
and seat should be checked for sealing ability. Also, the
cooling system should be checked for loose hose con-
nections, defective hoses, gasket leaks, etc.
Coolant System Checks
1.
Test for restriction in the radiator, by warming the
engine up and then turning the engine off and feeling
the radiator. The radiator should be hot at the top
and warm at the bottom, with an even temperature
rise from bottom to top. Cold spots in the radiator
indicate clogged sections.
2.
Water pump operation may be checked by running the
engine while squeezing the upper radiator hose. A
pressure surge should be felt Check for a plugged
vent-hole in pump.
NOTE:
A defective head gasket may allow ex-
haust gases to leak into the cooling system.
This is particularly damaging to the cooling
system as the gases combine with the water to
form acids which are particularly harmful to
the radiator and engine.
3.
To check for exhaust leaks into the cooling system,
drain the system until the water level stands just
above the top of the cylinder head, then disconnect
the upper radiator hose and remove the thermostat
and fan belt. Start the engine and quickly accelerate
several times. At the same time note any appreci-
able water rise or the appearance of bubbles which
CHEVROLET CHASSIS SERVICE MANUAL
ENGINE COOLING 6K-2
are indicative of exhaust gases leaking into the coolr
ing system.
Periodic Maintenance
Periodic service must be performed to the engine cool-
ing system to keep it in efficient operating condition.
These services should include a complete cleaning and
reverse flushing as well as a reconditioning service.
In the course of engine operation, rust and scale ac-
cumulate in the radiator and engine water jacket. The
accumulation of these deposits can be kept to a minimum
by the use of a good rust inhibitor but it should be
remembered that an inhibitor will not remove rust al-
ready present in the cooling system.
Two common causes of corrosion are: (1) air suction--
Air may be drawn into the system due to low liquid level
in the radiator, leaky water pump or loose hose con-
nections; (2) exhaust gas leakage—Exhaust gas may be
blown into the cooling system past the cylinder head
gasket or through cracks in the cylinder head and block.
Cleaning
A good cleaning solution should be used to loosen the
rust and scale before reverse flushing the cooling
system. There are a number of cleaning solutions avail-
able and the manufacturer's instructions with the particu-
lar cleaner being used should always be followed.
An excellent preparation to use for this purpose is GM
Cooling System Cleaner. The following directions for
cleaning the system applies only when this type cleaner
is-used.
1.
Drain the cooling system including the cylinder block
and then close both drain plugs.
2.
Remove thermostat and replace thermostat housing.
3.
Add the liquid portion (No. 1) of the cooling system
cleaner.
4.
Fill the cooling system with water to a level of about
3 inches below the top of the overflow pipe.
5. Cover the radiator and run the engine at moderate
speed until engine coolant temperature reaches 180
degrees.
6. Remove cover from radiator and continue to run the
engine for 20 minutes. Avoid boiling.
7. While the engine is still running, add the powder
portion (No. 2) of the cooling system cleaner and
continue to run the engine for 10 minutes.
8. At the end of this time, stop the engine, wait a few
minutes and then open the drain cocks or remove
pipe plugs. Also remove lower hose connection.
CAUTION: Be careful not to scald your hands.
NOTE:
Dirt and bugs may be cleaned out of
the radiator air passages by blowing out with air
pressure from the back of the core.
Reverse Flushing
Reverse flushing should always be accomplished after
the system is thoroughly cleaned as outlined above.
Flushing is. accomplished through the system in a direc-
tion opposite to the normal flow. This action causes the
water to get behind the corrosion deposits and force
them out.
Radiator
1.
Remove the upper and lower radiator hoses and re-
place the radiator cap,
2.
Attach a lead-away hose at the top of the radiator.
3.
Attach a new piece of hose to the radiator outlet
connection and insert the flushing gun in this hose.
4.
Connect the water hose of the flushing gun to a water
outlet and the air hose to an air line.
5. Turn on the water and when the radiator is full, turn
on the air in short blasts, allowing the radiator to
fill between blasts of air.
CAUTION: Apply air gradually as a clogged
radiator will stand only a limited pressure.
6. Continue this flushing until the water from the lead-
away hose runs clear.
Cylinder Block and Cylinder Head
1.
With the thermostat removed, attach a lead-away
hose to the water pump inlet and a length of new hose
to the water outlet connection at the top of the engine.
NOTE:
Disconnect the heater hose when re-
verse flushing engine.
2.
Insert the flushing gun in the new hose.
3.
Turn on the water and when the engine water jacket
is full, turn on the air in short blasts.
4.
Continue this flushing until the water from the lead-
away hose runs clear.
Hot Water Heater
1.
Remove water outlet hose from heater core pipe.
2.
Remove inlet hose from engine connection.
3.
Insert flushing gun and flush heater core. Care must
be taken when applying air pressure to prevent
damage to the core.
Fan Belt
Adjustment
1.
Loosen bolts at Delcotron slotted bracket.
2.
Pull Delcotron away from engine until desired ten-
sion reading is obtained with a strand tension gauge.
Refer to Section 6, "Engine Tune-Up".
3.
Tighten all Delcotron bolts securely.
Thermostat
The thermostat consists of a restriction valve actuated
by a thermostatic element. This is mounted in the hous-
ing at the cylinder head water outlet above the water
pump,
thermostats are designed to open and close at
predetermined temperatures and if not operating properly
should be removed and tested as follows.
Replacement
1.
Remove radiator to water outlet hose.
2.
Remove thermostat housing bolts and remove water
outlet and gasket from thermostat housing (fig. 2).
3.
Inspect thermostat valve to make sure it is in good
condition.
4.
Place thermostat in hot water 25° above the temper-
ature stamped on the thermostat valve.
5. Submerge the valve completely and agitate the water
thoroughly. Under this condition the valve should
open fully.
6. Remove the thermostat and place in water 10° below
temperature indicated on the valve.
7. With valve completely submerged and water agitated
thoroughly, the valve should close completely.
8. If thermostat checks satisfactorily, re-install, using
a new housing gasket.
9. Refill cooling system.
CHEVROLET CHASSIS SERVICE MANUAL
ENGINE FUEL
6M-10
the
two
"FILL71 lines
(fig.
6A). Refill whenever
the
level
falls below the lower
<'FILL"
line.
Storing Tool
When
the
tool
is
not used, fully depress
the
inner tube.
This seals
off
the
oil
reservoir from the vent hole
to pre-
vent
oil
loss
if
the tool
is
tipped.
Fig. 6A-Filling Tool with
Oil
FUEL PUMP
INDEX
Page
General Description
. . . . 6M-10
Service Procedures .6M-10
Inspection .6M-10
Page
Test
. . ; 6M-10
Removal
6M-11
Installation
6M-11
GENERAL DESCRIPTION
The fuel pump
(fig. IP)
used
on all
Chevrolet vehicles
covered
in
this manual
are of the
diaphragm type.
The
pumps
are
actuated
by an
eccentric located on
the
engine
camshaft.
On
in-line engines,
the
eccentric actuates
the
rocker arm*
On V-8
engines,
a
push
rod
(located be-
tween
the
camshaft eccentric and fuel pump) actuates
the
pump rocker
arm.
Because
of
design, this pump
is
serviced
as an
assembly only.
Fig.
IP—Fuel Pump (Non-Serviceable)
SERVICE PROCEDURES
Inspection
The fuel pump should
be
checked
to
make sure
the
mounting bolts
and
inlet and outlet connections
are
tight.
Test
Always test pump while
it is
mounted on the engine
and
be sure there
is
gasoline
in
the tank.
The line from
the
tank
to the
pump
is the
suction side
of
the
system and the line from the pump
to the
carbure-
tor
is the
pressure side
of the
system.
A
leak on
the
pressure side, therefore, would
be
made apparent
by
CHEVROLET CHASSIS SERVICE MANUAL