STEERING 9-34
Fig.
64-Over Center Adjustment
transmission fluid "Type A" bearing the mark
"AQ-ATF" followed by a number and the suffix
letter "A".
ADJUSTMENTS
POWER STEERING GEAR
Chevrolet, Chevelle, and Camaro
The over-center adjustment (fig. 64) is the only power
steering gear adjustment which can be made on the car.
However, in order to make this adjustment, it is also
necessary to check the combined ball and thrust bearing
preload.
If the vehicle is equipped with a tilt column it will be
necessary to disconnect the steering coupling to obtain a
torque reading of the column. This torque should then be
subtracted from any reading taken on the gear.
1.
Disconnect the pitman arm from the relay rod.
2.
Loosen the pitman shaft adjusting screw loeknut and
thread the adjusting screw out to the limit of its
travel through the side cover. '. •
3.
Disconnect steering column harness at chassis wir-
ing connector plug.
4.
Remove horn button.
5.
Turn the steering wheel through its full travel, then
locate the wheel at its center of travel.
6. Gheck the combined ball and thrust bearing preload
with an inch-pound torque wrench on the steering
shaft nut by rotating through the center of travel
(approximately 1/4 turn in each direction). Note the
highest reading.
7.
Tighten the pitman shaft adjusting screw and check
torque at steering shaft nut until over center preload
and total steering gear preload falls within speci-
fications. Refer to torque specifications at rear of
manual for correct torque values.
8. Install horn button. Connect steering column harness
at wiring connector plug.
Chevy II and Corvette
The steering gear used with power steering is adjusted
in the same manner as the manual steering gear.
PUMP BELT TENSION
1.
Loosen nut on pivot bolt and pump brace adjusting
nut.
CAUTION: Do not move pump by prying against
reservoir or by pulling on filler neck.
2.
Move pump, with belt in place until belt is tensioned
to specifications as indicated by Tool J-7316 (Fig-.
65).
3.
Tighten pump brace adjusting nut. Then tighten pivot
bolt nut.
HYDRAULIC SYSTEM CHECKS
The following procedure outlines methods to identify
and isolate power steering hydraulic circuit difficulties.
This test is divided into two parts. Test number one
provides means of determining whether power steering
system hydraulic parts are actually faulty. If test number
one results in readings indicating faulty hydraulic opera-
tion, test number two will identify the faulty part. Be-
fore performing hydraulic circuit test, carefully check
belt tension and condition of driving pulley. Strand
tension of belt should be 125 lbs. on new belts and 75 lbs.
on old belts, as indicated by Tool J-7316 (Fig. 65).
Test Number One—Oil Circuit Open
Engine must be at normal operating temperature. In-
flate front, tires to correct pressure. All tests are made
with engine idling, so adjust engine idle speed to correct
specifications listed in Section 6 and proceed as follows:
a. With engine not running, disconnect flexible pres-
sure line from pump and install Tool J-5176 as
Fig.
65— Checking Belt Tension with Tool J-7316
CHEVROLET CHASSIS SERVICE MANUAL
STEERING 9-35
Fig.
66—Power Steering Diagnosis
shown in Figure 66. Gauge must be between shut-
off valve and pump. Open shut-off valve,
b.
Remove filler cap from pump reservoir and check
fluid level. Fill pump reservoir to full mark on
dip stick. Start engine and, holding steering
wheel against stop, check connections at Tool
J-5176 for leakage. Bleed system as outlined
under Maintenance and Adjustments. Insert ther-
mometer (Tool J-5421) in reservoir filler open-
ing. Move steering wheel from stop to stop
several times until thermometer indicates that
hydraulic fluid in reservoir has reached tempera-
ture of 150° to 170°F.
CAUTION: To prevent scrubbing flat spots on
tires,
do not turn steering wheel more than five
times without rolling car to change tire-to-floor
contact area.
c. Hold steering wheel against a stop momentarily
and read pressure gauge. If the maximum pres-
sure is below specifications, a faulty hydraulic
circuit is indicated. To determine which part is
faulty, proceed with test number two.
Test Number Two—Oil Circuit Closed
a. Slowly turn shut-off valve on J-5176 to closed
position and read pressure indicated on gauge.
Quickly reopen valve to avoid pump damage, if
indicated pressure is less than specification,
pump output is below requirement and pump may
be considered faulty. If pressure indicated is
within specifications, it may be safely assumed
that the external hoses, connections, valve and
adapter or steering gear is at fault.
NOTE:
If pump proves faulty in test number
two,
test should be repeated after pump is re-
paired and installed in vehicle. This will provide
a means of checking the repairs made to the
pump and the condition of the steering gear or
valve and adapter which may also be faulty.
COMPONENT REPLACEMENT AND REPAIRS
POWER STEERING PUMP
Removal (Fig. 67)
1.
Disconnect hoses at pump. When hoses are discon-
nected, secure ends in raised position to prevent
drainage of oil. Cap or tape the ends of the hoses to
prevent entrance of dirt.
NOTE:
Chevelle with 396 engine uses a remote
reservoir. It is necessary to disconnect the
reservoir to pump hose before removing the
pump.
Hold a 1 qt. container under the reservoir
when the hose is removed to catch the fluid.
2.
Install two caps at pump fittings to prevent drainage
of oil from pump.
3.
Remove pump belt.
4.
On Corvette with 427 engine, loosen alternator ad-
justment and remove pump to alternator belt.
5. Remove pump from attaching parts and remove pump
from vehicle.
NOTE:
On Chevrolet and Chevy II equipped with
283 and 327 engine it may be necessary to re-
move pump brace.
6. Remove drive pulley attaching nut.
7. Remove pulley from shaft with Tool J-21239 (for
stamped pulleys) or Tool J-8433-1 with J-8433-2
adapter (for cast iron pulleys). Do not hammer
pulley off shaft as this will damage the pump.
Fig.
67—Power Steering Pump Mounting
CHEVROLET CHASSIS SERVICE MANUAL
STEERING 9-37
NUT
Fig.
69—Control Valve Ball Stud Seal Replacement
(Service Type)
4.
Center the ball stud, seal and clamp at opening in
adapter housing, then install spacer, bolt and nut.
Removal
1.
Raise the front of the vehicle off the floor and place
it on stands.
2.
Remove the relay rod to control valve clamp bolt.
3.
Disconnect the two pump to control valve hose cdn-
nections and allow fluid to drain into a container,
then disconnect the two remaining valve to power
cylinder hoses.
4.
Remove the retaining nut from the ball stud to pitman
arm connection and disconnect the control valve
from the pitman arm.
5. Turn the pitman arm to the right clear of the control
valve and unscrew the control valve from the relay
rod.
6. Remove the control valve from the vehicle.
Installation
1.
Install the control valve on the vehicle by reversing
the removal procedure.
2.
Reconnect the hydraulic lines, fill the system with
fluid and bleed out air using the procedure outlined
under "Maintenance and Adjustments/' Grease ball
joint.
POWER CYLINDER (Fig. 70)
Chevy II and Corvette
Removal
1.
Disconnect the two hydraulic lines connected to the
power cylinder and drain fluid into a container. Do
not reuse.
2.
Remove cotter pin, nut, retainer and grommet from
power cylinder rod attached to the frame bracket.
3.
Also remove grommet and retainer from bracket if
replacement parts are required.
1.
Snap Ring
2.
End Plug and
Lube Fitting
3.
"O" Ring
Fig.
70—Power Cylinder—Exploded View
4.
Spring
5. Spring Seat
6. Ball Stud
7. Ball Seat
8. Ball Stud Seal
9. Piston Body
10.
Piston Rod Seal
11.
Backup Washer
•12.
Scraper Element
13.
Piston Rod Scraper
14.
Snap Ring
15.
Piston Rod
CHEVROLET CHASSIS SERVICE MANUAL
STEERING 9-39
4.
Remove cotter pin, nut and ball stud at relay rod.
5. Remove the power cylinder from the vehicle.
Inspection
1.
Inspect the seals for leaks; if leaks are present,
replace the seals using the procedure outlined under
"Disassembly."
2.
Examine the brass fitted hose connection seats for
cracks or damage and replace if necessary.
3.
For service other than ball seat or seal replacement
and ball stud removal, replace the power cylinder.
4.
Check the frame bracket parts for wear.
Disassembly
1.
To remove the piston rod seal remove the snap ring;
then pull out on the rod, being careful not to spray
oil.
2.
Remove the piston rod scraper and scraper element,
back up washer and piston rod seal from the rod.
3.
At the ball stud end of the cylinder, remove the ball
stud seal.
4.
Remove the snap ring retaining the end plug with the
lube fitting.
5. Push on the end of the ball stud and remove the end
plug, spring, spring seat and ball stud.
6. Remove the "O" ring seal from the top lip of the
power cylinder ball stud opening.
7. If the ball seat is to be replaced, it must be pressed
out using Tool J-8937.
Assembly
1.
Reassemble the piston rod seal components by re-
versing the disassembly procedure. Apply a thin
coat of Lubriplate or equivalent on the inner sur-
faces of the seal and scraper before assembly.
2.
Reverse the disassembly procedure when reassem-
bling the ball stud.
3.
In each case be sure that the snap ring is securely,
seated in the ring groove.
Installation
1.
Install the power cylinder on the vehicle by reversing
the removal procedure.
2.
Reconnect the two hydraulic lines, fill the system
with fluid and bleed out air using the procedure out-
lined under "Maintenance and Adjustments." Grease
ball joint.
POWER STEERING HOSES
When servicing the power steering hoses be sure to
align the hoses in their correct position as shown in
Figure 71. On Chevelle models with 396 engine, install
the upper hose so that there is at least .6 inch clearance
between the hose and the Delcotron or the inner fender
skirt.
It is important that the power steering hoses be in-
stalled correctly. Hoses installed out of position may be
subjected to chafing or other abuses during sharp turns.
Always make hose installations with front wheels in
straight ahead position. Do not twist hoses unneces-
sarily during installation.
CAUTION: Do not start engine with any power
steering hose disconnected.
CHEVROLET CHASSIS SERVICE MANUAL
WHEELS AND TIRES 10-4
the road and it slips, grinding off the tread on the inside
half of the tire at an excessive rate. This type of tire
shows much the same appearance of tread wear as tire
wear caused by negative camber.
Second, the transfer of weight may also over-load the
outside tires so much that they are laterally distorted
resulting in excessive wear on the outside half of the
tire producing a type of wear like that caused by ex-
cessive positive camber.
Cornering wear can be most easily distinguished from
abnormal camber wear by the rounding of the outside
shoulder or edge of the tire and by the roughening of the
tread surface which denotes abrasion.
Cornering wear often produces a fin or raised portion
along the inside edge of each row in the tread pattern.
In some cases this fin is almost as pronounced as a
toe-in fin, and in others, it tapers into a row of tread
blocks to such an extent that the tire has a definite step
wear appearance.
The only remedy for cornering wear is proper in-
struction of owners.
Fig.
5 - Tire Rotatidh
Rotation
To minimize the possibility of tire noise and to equal-
ize tire wear, it is recommended that tires be inter-
changed every 6000 miles as shown in Figure 5 or more
frequently in the case of extremely heavy wear.
NOTE:
Rotate Corvette tires at 4000 miles or
sooner.
Interchanging tires will effectively prevent undue wear
on any particular tire. II tire interchanging is followed
as recommended above, all tires will have the same
number of miles in each wheel position at the end of the
fourth change. When interchanging tires, inspect for
signs of abnormal wear, bulging, etc., stones, glass, and
nails should be removed before reinstallation.
Noise
Noise caused by the normal action of tire treads on
various road surfaces is often confused with rear axle
gears or other noises in the car.
The determination of whether tires are causing the
noise complained of is relatively simple. The car should
be driven at various speeds and note taken of part
throttle, and sudden acceleration and deceleration. Axle
and exhaust noises show definite variations under these
conditions, while tire noise will remain constant. Tire
noise is, however, most pronounced at speeds of approx-
imately twenty or thirty miles per hour.
The tires may be further checked by driving the ear
over smooth pavement with the tires at normal pressure
and again over the same stretch of pavement when the
tires have been inflated to fifty pounds pressure. Reduce
the tires to normal pressure one at a time to determine
the faulty tire or tires. This high inflation pressure
should immediately be reduced to normal after test. If
the noise for which the test is being made is caused by
tires,.
it will noticeably decrease when the tire pressure
is increased, whereas axle noise should show no change
in volume.
If, on inspection, the tires on the front wheels are
found to be creating most of the noise the alignment of
the front wheels should be checked. Excessive tire noise
usually results from lower than recommended tire pres-
sure, incorrect alignment, uneven tire wear, or defective
(thumper) tire.
Cleaning
A great deal of ordinary road dirt which collects on
white sidewall tires may be sponged off with clear water
or a mild soap solution.
A good brand of whitewall tire cleaner, however, is
a quicker and more effective cleaner for removing dirt
and stains from whitewall tires and in many cases it
will remove stains and discoloration that the simpler
method of soap and water will not remove.
Under no circumstances should gasoline, kerosene or
any cleaning fluid containing a solvent derived from oil
be used to clean whitewall tires. Oil in any form is
detrimental to tire rubber and a cleaner with an oil base
will discolor or injure whitewall tires.
Change (W/Wheels)
To change the road wheels using the jack that comes
with the car, observe the following procedure:
1.
Set hand brake and block front wheels if rear wheel
is being changed.
2.
Remove hub cap or wheel disc and break wheel
mounting nuts loose.
3.
Place the jack as directed tinder, General Informa-
tion,
Section 0 and raise car until wheel clears
ground.
4.
Remove wheel mounting nuts and remove wheel from
hub or drum.
5. To replace road wheel, reverse the above instrue-
. tions. Proper torque on nuts is 55-75 ft. lbs.
torque (70-85 ft. lbs. for Corvette aluminum wheel
nuts).
CAUTION: On models equipped with discs, in-
dex the pilot hole in the disc on the valve stem.
(To insure that the anti-rotation notches in wheel
disc register on lugs in wheel rim.)
CHEVROLET CHASSIS SERVICE MANUAL
ELECTRICAL-BODY
AND
CHASSIS
12-66
R.H. PARK
&DIR.
SIG. LP
L.H. PARK
& DQU SIG.
LP,
GROUND
TO
FENDER REINF
BRAKE FLUID
ill WARNING SW.
Fig.
109 - Front Lighting and Engine Compartment — (Chevelie)
CHEVROLET CHASSIS SERVICE MANUAL
ELECTRICAL-BODY AND CHASSIS 12-74
R.H. PARK&
DIR. SIG. LAMP
\L2 BRNf
18 Y—
12 BRN
18 LBL4-
18DBL
12 P
18 LG
18 P
DASH
PANEL
RESISTOR
TEMP.
SENDER
R.H. LIMIT SW.
L.H. LIMIT SW.
GY/B,
16 DBL
BRK FLUID
WARNING
16
W
20 OR
20 B
BACK-UP
LMP.
SW,
20 B
16 B/W
18 T
NEU.
SFT.
SW. I
RPO
M35
4BRN/W
16 B
M18DG
4 OR
DIR. SIG.
&
DIR.
SIG. LAMP
Fig. 117 - Front Lighting & Engine Compt — Corvette
CHEVROLET CHASSIS SERVICE MANUAL