Page 424 of 659

FUEL TANK
AND
EXHAUST SYSTEMS
8-18
CORVETTE
FUEL TANK
INDEX
Page
General Description.
. 8-18
Service Operations
8-18
Fuel Tank
8-18
Gauge Sending Unit
8-20
Fuel Lines.
8-20
GENERAL DESCRIPTION
20 GALLON TANK
Fig.
21
—Corvette Fuel Tanks
The Corvette
is
equipped with
a
standard
20
gallon
(approx.) tank
or an RPO 36
gallon (approx.) fiberglass
tank
(fig. 21). The
tanks
are
installed
at the
very rear
of
the
vehicle, convenient
for
direct fuel filling into
the
tank.
The
tanks
are
held
in
place
by
two metal straps
at-
tached individually
to a
removable
gas
tank frame
sup-
port.
Two
guides
at the end of
the straps
are
adjustable
for securing
the
straps onto
the
tank support. The tank
support
is
secured
to the
frame rail with flat washers,
lockwashers, bolts
and
nuts.
The
tanks' rest
on six
felt
anti-squeak pads.
One pad
centers
on the
rear frame
crossmember
and one at
each side
on the
same cross-
member.
At the
same rear location two pads
are
placed
on
the
tank
at the
metal support strap (rear) attachment
location
and
another anti-squeak
pad
cemented
on the
support
at
the front
of
the tank.
The fuel tanks
are
equipped with
a gas
gauge metering
unit,
a
fuel pickup, fuel strainer
and
vent line.
If it be-
comes necessary,
the
tank
can be
completely drained
by
removing
the
fuel pickup hose which
is
located
at
the
bot-
tom
of the
tank,
or
by removing the metering
for
quicker
draining.
A pressure vacuum type, positive vented design
cap,
conforming
to
I.C.C. regulations,
is
used on both regular
production
and
optional fuel tanks.
The cap is
inter-
changeable with past model tanks
for
service replace-
ment purposes.
SERVICE OPERATIONS
FUEL TANK
CAUTION:
IF THE GAS
TANK SHOULD
BE
REMOVED
AND
INSTALLED, CARE SHOULD
BE EXERCISED
TO
AVOID PUNCTURING,
DROPPING
OR
DENTING
THE GAS
TANK.
Removal
(20
Gallon Tank)
WARNING: FIRST REMOVE BATTERY
CABLE.
1.
Remove
the
spare tire from tire carrier.
2.
Remove spare tire carrier bolted attachments
and
carrier
(fig. 22).
3.
Remove
the "U"
bolt attachments
at
both rear tail
pipe
(See
Figure
23).
4.
Separate
the
exhaust system
at
the transmission sup-
port crossmember
by
loosening
the "U"
bolt nuts.
5. Remove both rear muffler brackets from
the
frame
and slide
the
muffler system rearward.
CHEVROLET CHASSIS SERVICE MANUAL
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FUEL TANK AND EXHAUST SYSTEMS 8-19
Fig.
22—Spare Tire Carrier Installed
6. Remove two fuel tank retaining strap bottom nuts
from forward support member located at forward
front side of tank.
7. Remove fuel tank metering unit wires (fig. 25).
8. Remove fuel pickup line and drain tank.
9. Remove gas cap, filler neck boot from the top of tank
and disconnect drain line (fig. 24).
NOTE:6
Coupe Models—Remove filler neck.
10.
Remove fuel tank support frame attachment bolts and
support.
11.
Lower tank and rotate toward the front of vehicle.
Installation (20 Gallon Tank)
NOTE:
Place hoses and wires to one side and
position anti-squeak pads to the crossmember,
END OF HOSE FLUSH
TO Va INCH BACK FROM
EDGE OF BUMPERETTE
Fig.
24-Gas Tank Filler Neck Vent Hose
cemented to the support and attached to the tank.
Replace with new pads as required.
1.
Hook retaining straps at the rear frame crossmem-
ber. (Crimp strap ends at rear frame attachment.)
NOTE:
Make certain strap ends are hooked and
anti-squeak pads are properly positioned.
2.
Slowly rotate fuel tank into position.
CAUTION: Coupe-Install filler neck after tank
is installed.
3.
Attach fuel tank support at the frame side rails.
TANK METERING UNI
WIRE CONNECTIONS
Fig.
23—Exhaust System Tail Pipe Attachment
Fig.
25—Fuel Tank Metering Unit, Wires and Lines
CHEVROLET CHASSIS SERVICE MANUAL
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FUEL TANK AND EXHAUST SYSTEMS 8-20
4.
Attach the retaining straps with strap guide attached
to the fuel tank support, and secure with-the nut and
lockwasher assembly.
5. Connect the filler neck boot to the drain hose of the
tank and install boot around filler neck,
6. Connect the fuel pickup line, ground wire and make
certain that the fuel drain line is flush to 1/2" in-
board of the rear bumper opening.
7. Attach tank metering unit wires (fig. 25).
8. Replace fuel in tank. Replace gas cap.
9. Check for possible leaks.
10.
Reconnect the exhaust system by reversing the above
removal procedures (see "Exhaust System").
11.
Install spare tire carrier by securing the bolt
attachment.
12.
Install the spare tire in the tire carrier.
Removal (36 Gallon Tank)
1.
Remove cover (fig. 26).
2.
Disconnect hoses and drain tank and remove two
fittings at bottom of tank.
3.
Disconnect fuel and vent lines and wires at tank
(fig. 27).
4.
Remove straps.
installation (36 Gallon Tank)
Reverse removal procedure to install.
FUEL TANK METERING UNIT OR GAUGE
SENDING UNIT AND STRAINER
The fuel tank metering unit is located at the bottom of
the fuel tank. The fuel strainer is attached at the end of
the sending unit inside the tank.
Replacement (20 Gallon Tank)
1.
Follow fuel tank removal procedure through Step 2.
2.
Drain the tank. Disconnect the attaching wires.
3.
Remove metering unit with a fuel tank gauge unit
Spanner J-8950 (revised).
4.
'Remove metering unit and gasket.
CAUTION: Carefully remove unit so as not to
damage screen on the end of the pipe.
5. Clean strainer screen by blowing out with com-
pressed air.
6. Reverse procedure to install.
Replacement (36 Gallon Tank)
1.
Remove cover.
2.
Follow Steps 2 thru 6 as outlined under replacement
for 20 gallon tank.
FUEL LINES
20 Gallon Tank
The fuel lines are conveniently located along the out-
side of the right frame rail (fig. 28). The lines extend
Fig.
26—Gasoline Tank (36 Gallon) Compartment Cover
from the fuel tank pickup at the bottom of the tank, along
the rear frame crossmember to the right frame rail,
extending through the rail at the kickup area and along the
top inside edge of the frame to the fuel pump, Flexible
hoses are located at the fuel tank pickup and at the fuel
pump.
36 Gallon Tank
The 36 gallon tank fuel lines are routed from the bot-
tom of both sides of the tank to the right frame rail
(fig. 20).
Maintenance
CAUTION: Always drain gasoline from the
complete fuel system including carburetor, fuel
pump and all fuel lines and fuel tank if the vehi-
cle is to be stored for any great length of time.
This precaution will prevent accumulation~ol
gum formation and resultant poor engine
performance.
. The fuel lines should occasionally be inspected for
leaks,
kinks or dents, especially when work has been
done on the underside of car or after the car has been
traveling over rough or stone roads at higher speeds.
If evidence of dirt is found in the carburetor or fuel pump
at disassembly, the lines should be disconnected and
blown put. Check the fuel tank strainer for damage or
omission.
Fuel lines are beaded-type ends for connection to
hoses and flared ends for secure metal-to-metal line
connections.
CHEVROLET CHASSIS SERVICE MANUAL
Page 427 of 659
FUEL TANK AND EXHAUST SYSTEMS 8-21
Fig.
27-Gasoline Tank (36 Gallon) Wiring
CHEVROLET CHASSIS SERVICE MANUAL
Page 428 of 659
Fig.
28-Corvette Fuel Lines (20 Gallon Tank)
Page 429 of 659
FUEL TANK AND EXHAUST SYSTEMS 8-23
CHEVROLET CHASSIS
saevia
Page 430 of 659

FUEL TANK
AND
EXHAUST SYSTEMS
8-24
EXHAUST SYSTEMS
INDEX
Page
General Description. ..........
8-24
Service Operations
8-24
Muffler Assembly.
8-24
Side Mounted Exhaust.
. . . 8-25
GENERAL DESCRIPTION
Fig.
30—Standard Dual
All Corvettes
are
equipped with dual exhaust systems
(fig.
30).
Each exhaust assembly
is
connected
to its own
exhaust manifold
and
carries
the
exhaust gases
to the
rear, discharging them
on
each side
of
the rear bumpers.
The dual exhaust system includes
two
front
and
rear
exhaust pipe sections, mufflers, tail pipes and attaching
hardware.
The
system
is
suspended
on
brackets with
insulators
for
rattle free operation. Adjustment
is
only
required
at the
rear muffler bracket.
In addition
to the
regular dual system
an
optional side
mounted, off-road exhaust system
is
available
as an
RPO
(fig.
31).
Extending between front
and
rear wheels,
the
dual units
are
mounted outboard
of the
frame side rails
at
the
rocker panel level,
and
completely replaces
the
regular dual assemblies*
Flow characteristics
are
improved and back pressures
reduced
by
the more direct exhaust routing and
by the use
of chambered pipes
for
sound muffling
in
place
of con-
ventional mufflers.
SERVICE OPERATIONS
Proper relationship
of
parts
is
necessary
in the ex-
haust system
for
carefree operation. Annoying rattles
are usually
a
result
of
incorrect alignment
of
the exhaust
system
due to
incorrect clearances.
MUFFLER ASSEMBLY
Replacement (Also Rear Exhaust
and
Tail Pipes)
Remove
"U"
bolt attachments
at
both rear tail pipe
shields.
2.
crossmember
1.
Separate
the
exhaust system
at the
tube
by
loosening the
"IT"
bolt nuts.
3.
Remove both rear muffler brackets from
the
frame
and slide
the
muffler system forward.
CAUTION: Before cutting
the
rear exhaust
pipe, measure service muffler exhaust pipe
end
and make certain
to
allow
1 1/2" for
engage-
ment
of the
rear exhaust pipe into service
muf-
fler pipe.
CHEVROLET CHASSIS SERVICE MANUAL
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FUEL TANK AND EXHAUST SYSTEMS 8-25
4.
Cut the exhaust pipe near the muffler (see cau-
tion above) to allow sufficient pipe for muffler
replacement.
5.
^
Replace muffler and secure with new clamps.
NOTE:
Clamps must be assembled with nuts
attached toward the rear of the vehicle -
reference 90° to sawcuts in service muffler
pipe.
6. Reverse procedure for installation.
NOTE:
If bracket mounting insulators (tire
carcass mountings) are fatigued, replace to in-
sure a secure exhaust system.
7. In the event the tail pipe bezel has been damaged and
replacement is required, remove three screws and
replace the bezel. i
SIDE MOUNTED EXHAUST (Fig. 31)
Replacement
1.
Raise and support vehicle.
2.
Remove sill molding attaching screws and disengage
molding from the retainer.
3.
Remove cover retaining screws, cover and retainer
assembly.
4.
Remove exhaust pipe-to-manifold attaching nuts, and
rear bracket retaining nut, then detach exhaust pipe
from manifold studs and remove from vehicle.
Fig.
31—Side Mounted Exhaust System
CHEVROLET
CHASSIS SEKVK