ENGINE FUEL 6M-7
5. On vehicles equipped with automatic transmission
hold throttle rod in full throttle position, pull TV
rod to full detent position and adjust TV rod to just
enter hole on throttle lever, then connect TV rod at
throttle lever.
NOTE:
If equipped with anti-stall device (dash-
pot),
set carburetor fast idle cam on high step
and adjust dash-pot to just contact throttle
lever.
327
CU.
IN.
427
CU.
IN.
Fig.
8C—Throttle Linkage-Corvette
AIR
CLEANERS
INDEX
Page
General Description 6M-7
Service Procedures . . 6M-8
Polyurethane. Element 6M-8
Maintenance 6M-8
Oil Bath 6M-8
Page
Maintenance
...........* 6M-8
Oil
Wetted
Paper
Element
6M-9
Replacement
* . 6M-9
Testing 6M-9
Tool J-7852 . 6M-9
GENERAL DESCRIPTION
Air cleaners on all models operate primarily to re-
move dust and dirt from the air that is taken into the
carburetor and engine. All air cleaners on engines
equipped with "Closed Positive" ventilation incorporate
flame arresters. Every 12,000 miles the flame ar-
resters should be removed, cleaned in solvent and blown
dry with compressed air.
An oil wetted polyurethane element air cleaner (fig. 1A)
is standard equipment on In Line engines. This type
cleaner element is reusable and should be removed,
cleaned, re-oiled and reinstalled every 12,000 miles or
more often during dusty or other adverse driving con-
ditions. The optional, oil bath air cleaner (available on
Chevrolets with L6 engine) should be cleaned and re-
filled with oil at oil change intervals.
On the V8 engines,, a replaceable, oil wetted paper
element type is used (fig; 2A). Both ends of me paper
element are bonded with plastisol sealing material.
The improved oil wetted paper elements have increased
filtering capacity over their dry paper predecessors.
Oil on the paper causes the element to become diBcolored
by a small amount of dirt but does not necessarily mean
the element is plugged or reduced in efficiency. Every
12,000 miles or more often during dusty or other adverse
driving conditions, either replace oil wetted paper ele-
ment or test element using ToolJ-7825.
CHEVROLET CHASSIS SOVICE/MANUAL
ENGINE FUEL 6M-8
^T^l^^/'-vN
COVER
BOTTOM
Fig. 1A—Polyurethane Element Air Cleaner
OIL RESISTANCE
SEAL
BOTTOM
BONDED PAPER
ELEMENT
COVER
Fig. 2A—Paper Element Air Cleaner
SERVICE
PROCEDURES
POLYURETHANE ELEMENT
Maintenance
1.
Remove cover wing nut, cover and filter element.
2.
Visibly check the element for tears or rips and re-
place if necessary.
3.
Clean all accumulated dirt and grime from air
cleaner bottom and cover. Discard air horn to air
cleaner gasket.
4.
/Remove support screen from element and wash
element in kerosene or mineral spirits; then squeeze
out excess solvent (fig. 3A).
NOTE: Never use a hot degreaser or any sol-
vent containing acetone or similar solvent*
5.
Dip element into light engine oil and squeeze out
excess oil.
NOTE: Never shake, swing or wring the ele-
me.nt to remove excess oil or solvent as this
may tear the polyurethane material. Instead,
"squeeze" the excess from the element.
6. Install element'on screen support (fig. 4A).
7.
Using a new gasket, replace air cleaner body over
carburetor air horn.
8. Replace the element in the air cleaner. Care must
be taken that the lower lip of the element is properly
placed in the assembly and that the filter material
is not folded or creased in any manner that would
cause an imperfect seal. Take the same precautions
when replacing the cover that the upper lip of the
element is in proper position.
9.<•
Replace cover and wing nut.
OIL BATH
Maintenance
L Remove air cleaner assembly.
2.
Remove cover and filter element assembly.
Empty oil out of
accumulated dirt.
cleaner and clean out all oil and
Fig. 3A—Cleaning Polyurethane Element
Fig.
4A—Polyurethane Support
CHEVROLET CHASSIS SERVICE MANUAL
ENGINE FUEL 6M-9
4.
Wash body with cleaning solvent and wip dry.
5. Wash filter element by sloshing up and down in
cleaning solvent.
6. Dry filter unit with an air hose or let stand until
dry.
7. Fill body of cleaner to full mark with SAE 50 engine
oil. If expected temperatures are to be consistently
below freezing, use SAE 20 engine oil.
8. Assemble filter and cover assembly to body of
cleaner.
9. Install cleaner, making sure it fits tight and is set
down securely. \
OIL
WETTED
PAPER
ELEMENT
Replacement
1.
Remove wing nut, washer and cover.
2.
Remove paper element and discard.
3.
Remove bottom section of air cleaner and gasket
on air horn of carburetor. Discard air horn gasket.
4.
Clean bottom section of air cleaner and cover pieces
thoroughly, to remove dust and grime.
NOTE:
Check bottom section of air cleaner
seal for tears or cracks.
5. Install a new gasket on carburetor air horn and set
bottom section of air cleaner on carburetor.
6. Install new paper element on bottom section of air
cleaner with either end up.
NOTE:
Plastisol seal is the same material on
both ends.
7. Install cover, washer and wing nut.
Testing (Fig. 5A)
Tool J-7825, is designed to check paper element air
cleaners to determine whether the element has ma-
terially decreased in efficiency arid should be replaced
or has only slightly increased air restriction and is
suitable for further service. In combination with a
tachometer, this instrument will quickly and accurately
determine the air cleaner element condition.
VENT HOLE
TOWARD DASH
NOTE:
t Before testing, inspect for holes or
breaks in the element, as these defects re-
quire immediate replacement. If no holes or
breaks exist, proceed as follows:
1.
Remove all hoses and plug all openings except air
cleaner inlet.
2.
Install air cleaner, using Tool J-7825 in place of the
wing nut. Screw Tool J-7825 onto the stud until it
seals tightly against the air cleaner cover. Rotate
the entire tool so that the scale can be read from
the left side of the car. Be sure the vent hole is
toward the dash.
3.
Connect a tachometer and place it so that it may be
read simultaneously with Tool J-7825.
4.
Zero oil level in the inner tube by pulling inner tube
upward until the rubber seal is above the vent hole,
then raise or lower as' required until the inner tube
oil level is exactly to the "0" mark.
5. Start engine. If engine is cold, allow to run for 2 to
3 minutes. The automatic choke must be fully open.
6. Accelerate the engine slowly until the inner tube oil
level of Tool J-7825 just reaches the 1/4 mark.
Allow engine speed to stabilize and note tachometer
(rpm) reading. Decelerate engine.
7. If the tachometer reading is at or below the follow-
ing, the oil wetted paper air cleaner element is re-
stricted beyond the allowable limit and should be
replaced. If testing indicates that the element
restriction is satisfactory at 12,000 miles, the ele-
ment need not be replaced but should be retested
every 6,000 miles thereafter until replaced.
Engine
Displacement
283 cu.
in.
327 cu.
in.
350 cu. in.
396 cu.
in.
427 cu.
in.
Horsepower
195
210
275
300
325
350
295
325
350
385
390
425
Minimum
Allowable
RPM
2300
2100
210Q
2600
2600
1550
1950
1850
1850
2140
Fig.
5A—Testing Air Cleaner
8. Remove tachometer and Tool J-7825 from vehicle
and push down inner tube until seal is below vent
hole to prevent oil loss.
Tool J-7825
FiHing
Tool
Tool J-7825 is shipped dry and must be filled with the
red gauge oil (specific gravity .826) provided.
Pull the knurled inner tube completely out of the gauge
and add oil to the reservoir until the oil level is between
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
ENGINE FUEL 6M-11
dripping fuel, but a leak on the suction would not be ap-
parent except for its effect of reducing volume of fuel on
the pressure side.
1.
Tighten any loose line connections and look for bends
or kinks in lines.
2.
Disconnect fuel pipe at carburetor. Disconnect dis-
tributor to coil primary wire so that engine can be
cranked without firing. Place suitable container at
end of pipe and crank engine a few revolutions. If
little or no gasoline flows from open end of pipe then
fuel pipe is clogged or pump is inoperative. Before
removing pump disconnect fuel pipe at gas tank and
outlet pipe and blow through them with an air hose
to make sure they are clear. Reconnect pipes and
retest while cranking engine.
CAUTION: Whenever the engine is cranked re-
motely at the starter, with a special jumper
cable or other means, the primary distributor
lead must be disconnected from the negative
post on the coil and the ignition switch must be
in the "ON" position. Failure to do this will
result in a damaged grounding circuit in the
ignition switch.
3.
If fuel flows from pump in good volume from pipe
at carburetor, check fuel delivery pressure to be
certain that pump is operating withint specified limits
as follows:
a. Attach a fuel pump pressure test gauge to dis-
connect end of pump to carburetor pipe.
b.
Run engine at approximately 450-1,000 rpm (on
gasoline in carburetor bowl) and note reading on
pressure gauge.
c. If pump is operating properly the pressure will
be within specifications and will remain constant
at speeds between 450-1,000 rpm. If pressure
is too low, too high, or varies materially at dif-
ferent speeds, the pump should be replaced.
Removal
1.
Disconnect fuel inlet and outlet pipes at fuel pump.
Fig.
2P-Installing 283, 327, 350 V8 Engine Fuel Pump
2.
Remove fuel pump mounting bolts and remove pump
and gasket.
3.
On V8 engines; if push rod is to be removed, remove
pipe plug then remove push rod (396 and 427 cu. in.
engines), remove fuel pump adapter and gasket then
remove push rod (283 and 327 cu. in. engines).
4.
If a new fuel pump is to be installed, transfer
fittings.
Installation
1.
On V8 engines; if removed, install fuel pump push
rod and pipe fitting or fuel pump adapter. Use.
gasket sealer on gasket or pipe fitting.
2.
Install fuel pump using a new gasket and tighten
securely. Use sealer on fuel pump mounting bolt
threads.
NOTE:
On V8 engines, a pair of mechanical
fingers may be used to hold fuel pump push rod
up while installing fuel pump (fig. 2P).
3.
Connect fuel pipes to pump.
4.
Start engine and check for leaks.
CHEVROLET CHASSIS SERVICE MANUAL
ENGINE FUEL
6M-12
SPECIAL TOOLS
—1137
J-4552
J-5496,
J-7825
15
J-6058A
BENDING
TOOLS
J-5197
J-6556
J-9789
J-8328
Fig.
lT-Engine Fuel Special Tools
CHEVROLET CHASSIS SERVICE MANUAL
SECTION 6T
AIR INJECTION REACTOR SYSTEM
INDEX
Page
General Description 6T-1
Maintenance Procedures 6T>1
Drive Belt. ...-..' 6T-1
Inspection 6T-1
, Adjustment . . 6T-1
Replacement 6T-1
Drive Pulley . . . . 6T-1
Replacement 6T-1
Pump Pulley ....................... 6T-1
Replacement. 6T-1
Air Manifold, Hose and Tube
...........>*.
6T-2
Inspection . . 6T-2
Replacement 6T-2
Check Valve (s) 6T-3
Page
Inspection 6T-3
Replacement . . 6T-3
Mixture Control Valve 6T-3
Inspection 6T-3
Replacement 6T-3
Air Injection Tube 6T-4
Inspection . . . ... . . . .... 6T-4
Replacement 6T-4
Air Injection Pump 6T-4
Inspection 6T-4
Replacement . 6T-4
Pressure Relief Valve Replacement 6T-4
Special Tools 6T-5
GENERAL
The Air Injection Reactor (A.I.R.) System (fig. 1) con-
sists of: the air injection pump (with necessary brackets
and drive attachments), air injection tubes (one for each
cylinder), a mixture control valve, check valves (one for
In Line engines, two for V8 engines) and air manifold as-
semblies, tubes and hoses necessary to connect the
various components.
Carburetors and distributors for engines with the
A.I.R. System are designed, particularly, for these en-
gines;
therefore, they should not be interchanged with or
replaced by a carburetor or distributor designed for an
engine without the A.I.R. System.
The air injection pump (fig. 2) picks up fresh filtered
air from the air cleaner, compresses the air and injects
it through the air manifolds, hoses and injection tubes
into the exhaust system in the area of the exhaust valves.
The fresh air ignites and burns the unburned portion of
the exhaust gases in the exhaust system, thus minimizing
exhaust contamination.
The mixture control valve (fig. 3) when triggered by a
sharp increase in manifold vacuum, supplies the intake
manifold with fresh filtered air to lean out the fuel-air
DESCRIPTION
mixture and prevent exhaust system backfire.
The check valve(s) prevent exhaust gases from entering
and damaging the air injection pump, as back flow can
occur even under normal operating conditions.
When properly installed and maintained, the A.I.R.
System will keep exhaust emissions well below require-
ments. However, if any A.I.R. component or any engine
component that operates in conjunction with the A.I.R.
system should malfunction, the exhaust emissions might
be increased.
Because of the relationship between "Engine Tune
Up"
and "Unburned Exhaust Gases", the condition of
Engine Tune Up should be checked whenever the A.I.R.
System seems to be malfunctioning. Particular care
should be taken in checking items that affect fuel - air
ratio such as the crankcase ventilation system, the
carburetor and the carburetor air cleaner.
Because of the similarity of many parts, typical illus-
trations and procedures are used except where specific
illustrations or procedures are necessary to clarify the
operation. For Repair Procedures on the Air Injection
Pump,
refer to the Passenger Chassis Overhaul Manual.
MAINTENANCE PROCEDURES
Drive Belt
Inspection
• Inspect drive belt for wear, cracks or deterioration
and replace if required.
• Inspect belt tension and adjust if below 50 lb. using a
strand tension gauge.
Adjustment
• Loosen pump mounting bolt and pump adjustment
bracket bolt.
• Move pump until belt is tight (55±5 lb. used belt or
75±5 lb. new belt using a strand tension gauge) then
tighten adjustment bracket bolt and mounting bolt.
CAUTION: Do not pry on the pump housing.
Distortion of the housing will result in extensive
damage to the Air Injection Pump.
Replacement
• Loosen pump mounting bolt and pump adjustment
bracket bolt then swing pump until drive belt may be
removed.
• Install a new drive belt and adjust as outlined above.
Drive Pulley .
Replacement
• Remove drive belt as outlined above then replace
drive pulley.
• Install and adjust drive belt as outlined above.
Pump Pulley
Replacement
• Hold pump pulley from turning by compressing drive
belt then loosen pump pulley bolts.
• Remove drive belt as outlined above then remove
pump pulley.
• Install pump pulley with retaining bolts hand tight.
CHEVROLET CHASSIS SERVICE MANUAL
SECTION 8
FUEL TANK AND EXHAUST SYSTEMS
CONTENTS OF THIS SECTION
Page
Chevrolet .. . . 8-1
Fuel Tanks 8-1
Exhaust Systems 8-5
Chevelle 8-8
Fuel Tanks 8-8
Exhaust Systems 8-11
Chevy n ...... 8-13
Fuel Tanks 8-13
Page
Exhaust Systems 8-16
Corvette 8-18
Fuel Tanks 8-18
Exhaust Systems 8-24
Camaro 8-26
Fuel Tank 8-26
Exhaust System 8-30
Special Tools 8-33
CHEVROLET
FUEL TANKS
INDEX
Page
Page
General Description
Component Part Replacement
Fuel Tank
8-1 Fuel Lines 8-3
8-2 Fuel Tank Vent Lines 8-4
8-2 Metering Units (Gauge Sending Unit ) 8-4
GENERAL DESCRIPTION
All Sedan models (fig. 1) use a 24 gallon capacity
(approx.) fuel tank mounted between the frame rails
behind the rear axle. The fuel tanks are held in place
by two straps attached individually to the underbody at
each end. The strap? hinge at the forward end and secure
the tank at the rear with a nut and bolt. Anti-squeak
material is cemented to the tank at the strap locations.
A vent line from the forward-right side of tank extends
over a clip on the upper portion of wheelhouse.
The station wagon fuel tank has a 24 gallon capacity
(approx.). The tank is located at the back of the left rear
quarter wheelhouse area. The front of the tank is en-
closed with a protective shield (fig. 1).
VIEW A ^QUARTER PANEL
SEDAN
STATION WAGON
I
Fig.
1-Fuel
Tanks
CHEVROLET CHASSIS SERVICE MANUAL