ENGINE—ELECTRICAL 6Y-5
BATTERY TESTING PROCEDURES
Testing procedures are used to determine whether the
Battery is (1) good and usable, (2) requires recharging or
(3) should be replaced. Analysis of Battery conditions can
be accomplished, by performing a visual inspection,
Instrument Test, and the full charge hydrometer test.
1.
VISUAL INSPECTION
The first step in testing the Battery should be a visual
inspection, which very often will save time and expense
in determining Battery condition.
• Check the outside of the Battery for a broken or
cracked case or a broken or cracked cover. If any
damage is evident, the Battery should be replaced.
« Note the electrolyte level. Levels that are too low or
too high may cause poor performance, as covered in
the section entitled "Periodic Servicing".
o Check for loose cable connections, and for evidence
of corrosion as covered in section entitled ' 'Periodic
Servicing". Correct as required before proceeding
with tests.
2.
INSTRUMENT TEST
A number of suppliers have approved testing equipment
available. These testers have a programmed test proce-
dure consisting of a series of timed discharge and
charge events, requiring approximately 2 to 3 minutes,
that will determine the condition of the Battery with a
high degree of accuracy. When using these testers, the
procedure recommended by the tester manufacturer
should be followed. Batteries should not be charged prior
to testing as doing so may alter the test results. If a
tester is not available for testing, the "Specific Gravity
Cell Comparison Test" may be used or an alternate
method, but with a sacrifice in testing accuracy.
3. FULL CHARGE HYDROMETER TEST
This test should be used only on Batteries which test
good with testing equipment or "Specific Gravity Cell
Comparison Test" but which subsequently fail in service.
• Remove the Battery from the vehicle, and adjust the
electrolyte level as necessary, by adding colorless,
odorless, drinking water.
• Fully charge the Battery at the Slow Charging rate
as covered in the section entitled "Battery Charg-
ing".
• Measure the specific gravity of the electrolyte in
each cell and interpret as follows:
Hydrometer Reading Less Than
1.230—Full
charge
hydrometer readings less than 1.230 corrected for
temperature indicate the Battery is defective and
should be replaced.
Hydrometer Readings Above
1.310—Full
charge hy-
drometer readings above 1.310 corrected for tem-
perature indicate that the cells have been improperly
filled (activation) or improperly serviced. Poor
service and short Battery life will result.
SPECIFIC GRAVITY READINGS
A hydrometer can be used to measure the specific
gravity of the electrolyte in each cell.
The hydrometer measures the percentage of sulphuric
acid in the battery electrolyte in terms of specific
gravity. As a battery drops from a charged to a dis-
charged condition, the acid leaves the solution and enters
the plates, causing a decrease in specific gravity of
electrolyte. An indication of the concentration of the
electrolyte is obtained with a hydrometer.
When using a hydrometer, observe the following points:
1.
Hydrometer must be clean, inside and out, to insure
an accurate reading.
2.
Hydrometer readings must never be taken immedi-
ately after water has been added. The water must be
thoroughly mixed with the electrolyte by charging for
at least 15 minutes at a rate high enough to cause
vigorous gassing.
3.
If hydrometer has built-in thermometer, draw liquid
into it several times to insure correct temperature
before taking reading.
4.
Hold hydrometer vertically and draw in just enough
liquid from battery cell so that float is free floating.
Hold hydrometer at eye level so that float is vertical
and free of outer tube, then take reading at surface of
liquid. Disregard the curvature where the liquid
rises against float stem due to surface tension.
5.
Avoid dropping battery fluid on car or clothing as it
is extremely corrosive. Any fluid that drops should
be washed off immediately with baking soda solution.
The specific gravity of the electrolyte varies not only
with the percentage of acid in the liquid but also with
temperature. As temperature increases, the electrolyte
expands so that the specific gravity is reduced. As
temperature drops, the electrolyte contracts so that the
specific gravity increases. Unless these variations in
specific gravity are taken into account, the specific
gravity obtained by the hydrometer may not give a true
indication of the concentration of acid in the electrolyte.
A fully charged Battery will have a specific gravity
reading of approximately 1.270 at an electrolyte temper-
ature of 80°F. If the electrolyte temperature is above or
below 80°F, additions or subtractions must be made in
order to obtain a hydrometer reading corrected to the
80°F standard. For every 10° above 80°F, add four
specific gravity points (.004) to the hydrometer reading.
Example: A hydrometer reading of 1.260 at 110°F would
be 1.272 corrected to 80°F, indicating a fully charged
Battery. For every 10° below 80°F, subtract four points
(.004) from the reading. Example: A hydrometer reading
of 1.272 at 0°F would be 1.240 corrected to 80°F, indi-
cating a partially charged Battery.
Specific Gravity Cell Comparison Test—This test may
be used when a instrument tester is not available. To
perform this test measure the specific gravity of each
cell, regardless of state of charge, and interpret the
results as follows:
• If specific gravity readings show a difference be-
tween the highest and lowest cell of .050 (50 points)
or more, the Battery is defective and should be
replaced.
INSTALLING BATTERIES
To install a Battery properly, it is important to ob-
serve the following precautions:
• Connect grounded terminal of Battery last to avoid
short circuits which may damage the electrical
system.
CHEVROLET CHASSIS SERVICE MANUAL
CLUTCH
AND
TRANSMISSIONS
7-23
Assembly (Fig.
4X)
1.
With detent spring tang projecting
up
over
the 3rd
and
4th
shifter shaft cover opening install
the
first
and second detent
cam
onto
the
detent
cam
pivot
pin.
With
the
detent spring tang projecting
up
over
the
first
and
second shifter shaft cover hole install
the
3rd
and 4th
detent
cam,
NOTE:
The 1-2
detent
cam has a
.090" greater
contour
on the
inside detent notch.
2.
3.
Install detent
cam
retaining
"C"
ring
to
pivot shaft,
and hook spring into detent
cam
notches.
Install
1-2 and 3-4
shifter shaft assemblies
in
cover
being careful
not to
damage seals. Install both shift
forks
to
shifter shaft assemblies, lifting
up on
detent
cam
to
allow forks
to
fully seat into position.
4.
Install reverse detent ball
and
spring
to
cover, then
install reverse shifter shaft assembly
to
cover.
5.
Install outer shifter levers, flat washers, lock wash-
ers
and
bolts.
Installation
1.
Shift shifter levers into neutral detent (center) posi-
tion. Position cover gasket
on
case.
2.
Carefully position side cover into place making sure
the shift forks
are
aligned with their respective
mainshaft clutch sliding sleeves.
Install cover attaching bolts
and
tighten evenly
to
specified torque.
Remove filler plug
and add
lubricant specified
in
Section
0, to
level
of
filler plug hole.
3.
4.
ALUMINUM POWERGLIDE
INDEX
Page
General
Description
7-23
Maintenance
and
Adjustments .............. 7—23
Oil
Level Check
7-23
Periodic
Oil
Change
7-24
Periodic
Low
Band Adjustment
7-24
Manual
Shift Linkage Check
and
Adjust
7-24
Floor
Shift Linkage
7-25
Floor
Mounted Control Lever
and
Bracket
Assembly
7-29
Throttle
Valve Linkage
.... 7-29
Neutral
Safety Switch
.. . 7-30
Throttle
Return Check Valve (Dashpot)
7-30
Component
Parts Replacement
7-30
Transmission
Replacement .............. 7—30
Page
Other
Service Operations
7-32
Diagnosis
7-32
Warming
Up
Transmission
7-32
Shop
Warm
Up , 7-32
Road
Warm
Up 7-32
Checking
Fluid Level
and
Condition
7-32
Manual
Linkage
7-32
Oil
Leaks
7-33
Basic
Pressure Checks
7-33
Wide
Open Throttle Upshift Pressure Check
.... 7-33
Idle
Pressure
in
Drive Range
7-33
Manual
"Low"
Range Pressure Check .......
7-33
Drive
Range Overrun (Coast) Pressure
.
.......
7-33
Powerglide
Shift Points
. . 7-35
GENERAL DESCRIPTION
The case
and
converter housing
of the two
speed alumi-
num Powerglide Transmission
is a
single case aluminum
unit. When
the
manual control
is
placed
in the
drive
po-
sition,
the
transmission automatically shifts
to low
gear
for initial vehicle movement.
As the car
gains speed
and
depending
on
load
and
throttle position,
an
automatic shift
is made
to
high gear.
A
forced downshift feature
pro-
vides
a
passing gear
by
returning
the
transmission
to low
range.
The
oil
pump assembly
is a
conventional gear type
and
the
oil
pump housing
is of the
large diameter type acting
as
the
front bulkhead
of the
transmission.
The
torque
converter
is a
conventional three element welded design
bolted
to the
engine flywheel which drives through
a
two-
speed planetary gearset.
The
high clutch assembly
is
typical
of the
designs used
in
this type transmission.
The
aluminum Powerglide uses
an
output shaft mounted
gov-
ernor which requires
a
hole through
the
output shaft.
The
reverse clutch assembly
is a
multiple disc type clutch.
The steel plates
are
splined directly
to the
case while
the
face plates
are
splined
to the
internal
or
ring gear.
The
clutch piston operates within
the
rear portion
of the
case.
The internal diameter
of the
pistoh
is
sealed to
an
integral
hub portion
of the
case rear bulkhead.
The
outside
dia-
meter
is
sealed
to a
machined portion
of the
case.
The
piston
is
hydraulically applied
and is
released
by
separate
coil springs.
The
valve body assembly
is
bolted
to the
bottom
of the
transmission case
and is
accessible
for
service
by
removing
the oil pan
assembly.
The
valve
body consists
of an
upper
and
lower body located
on
either
side
of a
transfer plate.
The
vacuum modulator
is lo-
cated
on the
left rear face
of the
transmission case.
The
modulator valve bore
is
located
in the
upper valve body.
MAINTENANCE
AND
ADJUSTMENTS
OIL LEVEL CHECK
The transmission
oil
level should
be
checked period-
ically
as
recommended
in
Section
0. Oil
should
be
added
only when level
is on or
below
the
"ADD" mark
on the dip
stick with
oil hot or at
operating temperature.
The oil
level
dip
stick
is
located
at the
right rear
of the
engine
compartment. Fill with
oil
specified
in
Section
0.
In order
to
check
oil
level accurately,
the
engine should
be idled with
the
transmission
oil hot and the
control
lever
in
neutral (N) position.
It
is
important that
the oil
level
be
maintained
no
higher than
the
"FULL" mark
on the
transmission
oil
level gauge.
DO NOT
OVERFILL,
for
when
the oil
level
CHEVROLET CHASSIS SERVICE MANUAL
CLUTCH AND TRANSMISSIONS 7-24
is at the full mark on the dip stick, it is just slightly be-
low the planetary gear unit. If additional oil is added,
bringing the oil level above the full mark, the planetary
unit will run in the oil, foaming and aerating the oil. This
aerated oil carried through the various oil pressure pas-
sages (low servo, reverse servo, clutch apply, converter,
etc.) may cause malfunction of the transmission assem-
bly, resulting in cavitation noise in the converter and
improper band or clutch application. Overheating may
also occur.
If the transmission is found consistently low on oil, a
thorough inspection should be made to find and correct
all external oil leaks.
PERIODIC OIL CHANGE
The transmission oil should be changed periodically as
recommended in Section 0, and whenever transmission is
to be removed from the vehicle for repairs.
1.
Run engine for one minute in neutral prior to chang-
ing.
2.
Be sure vehicle is level or raise from the rear only.
3.
Remove the oil pan drain plug and allow oil to drain
thoroughly into a pan or can.
Replace drain plug and refill with approximately two
quarts of oil specified in Section 0.
NOTE: To refill the transmission, remove dip
stick from oil filler tube and refill transmission
with oil specified in Section 0 using filler tube
and funnel J-4264. Then, after shifting into all
ranges at idle speed to fill all oil passages, the
engine should be run at 800-1000 rpm with the
transmission in Neutral until the oil warms up,
then add oil as required to raise the fluid level
to the full mark on the dip stick. Refill capacity
is approximately 2 qts.
4.
Fig.
1PG - Adjusting Low Band Using J-21848
PERIODIC LOW BAND ADJUSTMENT (Fig. 1PG)
Low band adjustment should be periodically performed
at 12,000 mile intervals, or sooner, as necessary if op-
erating performance indicates low band slippage.
1.
Raise vehicle and place selector lever in neutral.
2.
Remove protective cap from transmission adjusting
screw.
3.
a. On Corvette Models: Drop left exhaust pipe for
clearance.
b.
On Chevelle Models: To gain clearance between
underbody and transmission, it may be necessary
to remove rear mount bolts from crossmember,
and move transmission slightly toward passenger
side of vehicle. .
4.
Loosen adjusting screw lock nut 1/4 turn and hold in
this position with wrench.
5.
Using Special Tool J-21848 adjust band to 70 in. lbs.
and back off four (4) complete turns for a band which
has been in operation for 6,000 miles or more,.or
three (3) turns for one in use less than 6,000 miles.
CAUTION: Be sure to hold the adjusting screw
lock nut at 1/4 turn loose with a wrench during"
the.adjusting procedure.
6. Tighten the adjusting screw lock nut to specified
torque.
CAUTION: The amount of back-off is not an
approximate figure, it must be exact.
MANUAL SHIFT LINKAGE CHECK & ADJUST
(Column Type)
1.
The shift tube and lever assembly must be free in the
mast jacket. See Section 9 for alignment of steering
column assembly if necessary.
2.
To check for proper shift linkage adjustment, lift
the transmission selector lever towards the steering
wheel. Allow the selector lever to be positioned in
drive (D) by the transmission detent.
NOTE: Do not use the indicator pointer as a
reference to position the selected lever. When
performing linkage adjustment, pointer is ad-
justed last.
3.
Release the selector lever. The lever should be in-
hibited from engaging low range unless the lever is
lifted.
4.
Lift the selector lever towards the steering wheel,
and allow the lever to be positioned in neutral (N) by
the transmission detent.
5.
Release the selector lever. The lever should now
be inhibited from engaging reverse range unless the
lever is lifted.
6. A properly adjusted linkage will prevent the selector
lever from moving beyond both the neutral detent, and
the drive detent unless the lever is lifted to pass
over the mechanical stop in the steering column.
7.
In the event that an adjustment is required, place
the selector lever in drive (D) position as determined
by the transmission detent. See Steps 2 and 3.
8. Loosen the adjustment swivel at the cross-shaft,
and rotate the transmission lever so that it contacts
the drive stop in the steering column.
9. Tighten the swivel and recheck the adjustment. See
2 and 6.
CHEVROLET CHASSIS SERVICE MANUAL
CLUTCH AND TRANSMISSIONS 7-32
21.
Remove transmission output shaft slip yoke and in-
sert a plastic shipping plug in end of extension to
prevent spillage of transmission fluid.
NOTE:
The yoke is removed to avoid tearing
the heat reflecting pad on the underbbdy, when
the transmission is being removed.
22.
Remove bright metal ignition shielding from dis-
tributor area.
23.
Remove the transmission dip stick and tube
assembly.
24.
Disconnect transmission vacuum modulator line at
distributor advance line tee.
25.
Position transmission hoist under transmission and
attach safety chain to transmission.
26.
Remove transmission converter housing-to-engine
attaching foolts and slide transmission rearward.
NOTE:
Observe converter when moving trans-
mission rearward. If converter does not move
with the transmission, pry it free of flywheel
before proceeding.
27.
Install converter retaining strap.
28.
Lower and remove transmission from vehicle by
tilting the front down and to the right while inter-
mittently lowering the transmission to facilitate its
• removal.
29.
Reinstall transmission assembly by performing the
above steps in reverse order.
Bolt Torques
Transmission Case to Flywheel
Housing Bolts 35 ft. lbs.
Converter to Flywheel Bolts. . , . . 35 ft. lbs.
OTHER SERVICE OPERATIONS
Although certain operations, such as oil pan or gasket
replacement, valve body, governor, filler pipe "O" ring,
speedometer drive gear, case extension "0" ring and
rear oil seal, vacuum modulator, and servo cover or
gasket service may be performed from underneath the
vehicle without removing the Powerglide; their service
procedure is covered in the Passenger Overhaul Manual
and is not repeated here. Refer to the- Powerglide Sec-
tion of the Passenger Overhaul Manual for all other
service operations not covered here.
DIAGNOSIS
Proper operation of the Powerglide transmission may
be affected by a number of factors, all of which must be
considered when trouble in the unit is diagnosed.
Proper trouble diagnosis can only be accomplished
when performed in a thorough step by step procedure.
The following procedure has been devised and tested and
is recommended for all trouble diagnosis complaints and
if the service man will follow this checking procedure,
accurate and dependable diagnosis may be accomplished.
This will result in a savings of time, not only to the
service man, but to the customer as well.
WARMING UP TRANSMISSION
Before attempting to check and/or correct any com-
plaints on the Powerglide transmission it is absolutely
essential that the oil level be checked and corrected if
necessary. An oil level which is either too high or too
low can be the cause of a number of abnormal conditions
from excessive noise to slippage in all ranges.
It must be remembered that cold oil will slow up the
action of the hydraulic controls in the transmission. For
this reason a trouble or oil leak diagnosis should not be
attempted until the transmission has been warmed up by
either of the following procedures:
Shop Warm Up
1.
Connect tachometer to engine.
2.
Set parking brake tight and start engine.
3.
Place selector light in
"D"
(drive) range.
4.
Adjust carburetor idle speed adjusting screw to run
engine at approximately 750 rpm and operate in this
manner for two minutes. At the end of two minutes
of operation, the transmission will be sufficiently
warmed up for diagnosis purposes.
NOTE:
At this point, readjust the engine idle
speed to 450-475 rpm in
"D"
range.
Road Warm Up
Drive the car approximately 5 miles with frequent
starts and stops.
NOTE:
At this point, make sure the engine idle
speed is set to 450-475 rpm in
"D"
range.
CHECKING FLUID LEVEL AND CONDITION
After transmission has been warmed up, check the
fluid level with the engine idling, parking brake set and
control lever in "N" (neutral). If the fluid level is low,
add fluid to bring level up to the full mark on gauge rod,
CAUTION: If fluid level is too high, fluid may
be aerated by the planet carrier. Aerated fluid
will cause turbulence in the converter which will
result in lost power, lower stall speed and lower
pressures in control circuits. Lower fluid level
to full mark, then shut off engine to allow air
bubbles to work out of fluid.
When checking oil level, aburned smell and discolora-
tion indicate burned clutches or bands and the transmis-
sion will have to be removed.
MANUAL LINKAGE
Manual linkage adjustment and the associated neutral
safety switch are important from a safety standpoint.
The neutral safety switch should be adjusted so that the
engine will start in the Park and Neutral positions only.
With the selector lever in the Park position, the park-
ing pawl should freely engage and prevent the vehicle
CHEVROLET CHASSIS SERVICE MANUAL
CLUTCH AND TRANSMISSIONS 7-36
TURBO HYDRA-MATIC TRANSMISSION
INDEX
Page
General Description . . , . 7-36
Maintenance and Adjustments . 7-37
Transmission Fluid 7-37
Fluid Level Indicator 7-37
Shift Control Linkage Adjustment ........... 7-37
Neutral Safety Switch Adjustment 7-37
Draining and Refilling Transmission . . . 7-37
Pressure Regulator Valve 7-38
Control Valve Body . 7-39
Governor ..'.... 7-40
Modulator and Modulator Valve 7-40
Parking Linkage . . 7-40
Page
Rear Seal -. 7-40
Other Service Operations . . 7-40
Transmission Replacement 7-40
Turbo Hydra-Matic Diagnosis Procedure. ......... 7-41
Sequence . ; ; 7-41
Oil Level and Condition Check 7-41
Manual Linkage 7-41
Oil Leaks .' 7-41
Case Porosity - Repair ................ 7-42
Oil Pressure Check 7-42
Transmission Shift Points 7-42
Special Tools 7-43
GENERAL DESCRIPTION
The Turbo Hydra-Matic transmission is a fully auto-
matic unit consisting primarily of a 3-element hydraulic
torque converter and a compound planetary gear set.
Three multiple-disc clutches, one sprag unit, one roller
clutch and two bands provide the friction elements re-
quired to obtain the desired function of the compound
planetary gear set.
The torque converter couples the engine to the plane-
tary gears through oil and provides hydraulic torque
multiplication when required. The compound planetary
gear set produces three forward speeds and reverse.
The
3-
element torque converter consists of a pump or
driving member, a turbine or driven member, and a
stator assembly. The stator is mounted on a one-way
roller clutch which will allow the stator to turn clock-
wise but not counter-clockwise.
The torque converter housing is filled with oil and
is attached to the engine crankshaft by a flex plate and
always rotates at engine speed. The converter pump is
an integral part of the converter housing, therefore the
pump blades, rotating at engine speed, set the oil within
the converter into motion and direct it to the turbine,
causing the turbine to rotate.
As the oil passes through the turbine it is traveling in
such a direction that if it were not re-directed by the
stator it would hit the rear of the converter pump blades
and impede its pumping action. So at low turbine speeds,
the oil is re-directed by the stator to the converter pump
in such a manner that it actually assists the converter
pump to deliver power or multiply engine torque.
As turbine speed increases, the direction of the oil
leaving the turbine changes and flows against the rear
side of the stator vanes in a clockwise direction. Since
the stator is now impeding the smooth flow of oil, its
roller clutch releases and it revolves freely on its shaft.
Once the stator becomes inactive, there is no further
multiplication of engine torque within the converter. At
this point, the converter is merely acting as a fluid
coupling as both the converter pump and turbine are
being driven at approximately the same speed - or at a
one-to-one ratio.
A hydraulic system pressurized by a gear type pump
provides the working pressure required to operate the
friction elements and automatic controls.
External control connections to transmission are:
Manual Linkage
Engine Vacuum
12 Volt Electrical
Signal
To select the desired op-
erating range.
To operate a vacuum mod-
ulator unit.
To operate an electrical
detent solenoid.
A vacuum modulator is used to automatically sense
any change in the torque input to the transmission. The
vacuum, modulator transmits this signal to the pressure
regulator for line pressure control, to the 1-2 accumula-
tor valve, and to the shift valves so that all torque re-
quirements of the transmission are met and smooth
shifts are obtained at all throttle openings.
The detent solenoid is activated by an alectric switch
on the carburetor. When the throttle is fully opened, the
switch on the carburetor is closed, activating the detent
solenoid and. causing the transmission to downshift at
speeds below approximately 70 MPH.
The selector quadrant has six selector positions: P,R,
N,D,
L2,L1.
P.
*
- Park position positively locks the output shaft to
the transmission case by means of a locking pawl
to prevent the vehicle from rolling in either di-
rection. The engine may be started in Park
position.
R. - Reverse enables the vehicle to be operated in a
reverse direction.
N.
- Neutral position enables the engine to be started
and run without driving the vehicle.
D,
- Drive Range is used for all normal driving condi-
tions and maximum economy. Drive Range has
three gear ratios, from the starting ratio to
direct drive. Detent downshifts are available by
depressing the accelerator to the floor.
L2.
- L2 Range has the same starting ratio as Drive
Range, but prevents the transmission from shift-
ing above second speed to retain second speed
acceleration when extra performance is desired.
L2 Range can also be used for engine braking.
L2 Range can be selected at any vehicle speed,
and the transmission will shift to second gear and
remain in second until the vehicle speed or the
throttle are changed to obtain first gear operation
in the same manner as in D Range.
CHIVROLET CHASSIS SERVICE MANUAL
CLUTCH AND TRANSMISSIONS 7-37
LI.
- LI Range can be selected at any vehicle speed,
and the transmission will shift to second gear
and remain in second until vehicle speed is re-
duced to approximately 40 MPH, .depending on
axle ratio. LI Range position prevents the trans-
mission from shifting out of first gear.
It is very important that any communication concerning
the Turbo Hydra-Matic always contain the transmission
serial number and that all transmission parts returned
to Chevrolet Motor Division always be tagged with the
transmission serial number.
MAINTENANCE AND ADJUSTMENTS
TRANSMISSION FLUID
Transmission fluid level should be checked with trans-
mission warm and selector lever in "P" Park position,
every time engine oil level is checked or as specified in
Section 0 when engine oil is changed.
CAUTION: Since the Turbo Hydra-Matic trans-
mission is very sensitive to oil level, special
precautions should be taken when checking the
oil level, to insure against an overfifE
Transmission fluid should be changed as specified in
Section 0.
FLUID LEVEL INDICATOR
The fluid level indicator is located in the filler pipe at
the right rear corner of the engine. To bring the fluid
level from the add mark to the full mark add 1 pint.
Fluid level should be to the full mark with transmission
at normal operating temperature. With cold fluid the
level should be at the add mark or slightly below.
SHIFT CONTROL LINKAGE ADJUSTMENT
Adjust linkage as shown below and in Figure 2.
1.
The shift tube and lever assembly must be free in the
mast jacket See Section 9 for alignment of steering
column assembly if necessary.
2.
To check for proper shift linkage adjustment, lift the
transmission selector lever towards the steering
wheel. Allow the selector lever to be positioned in
drive (D) by the transmission detent.
NOTE: Do not use the indicator pointer as a
reference to position the selector lever. When
performing linkage adjustment, pointer is ad-
justed last.
3.
Release the selector lever. The lever should be in-
hibited from engaging low range unless the lever is
lifted.
4.
Lift the selector lever towards the steering wheel,
and allow the lever to be positioned in neutral (N) by
the transmission detent.
5.
Release the selector lever. The lever should now be
inhibited from engaging reverse range unless the
lever is lifted.
6. A properly adjusted linkage will prevent the selector
lever from moving beyond both the neutral detent,
and the drive detent unless the lever is lifted to pass
over the mechanical stop in the steering column.
See schematic diagram.
7.
In the event that an adjustment is required, place the
selector lever in drive (D) position as determined by
the transmission detent. See Steps 2 and 3.
8. Loosen the adjustment swivel at the cross-shaft, and
rotate the transmission lever so that it contacts the
drive stop in the steering column.
9. Tighten the swivel and recheck the adjustment. See
Steps 2 and 6. -
l(h Readjust indicator needle if necessary to agree with
the transmission detent" positions. See Section 9.
11.
Readjust neutral safety switch if necessary to pro-
vide the correct relationship to the transmission de-
tent positions. See Section 12.
12.
When properly adjusted the following conditions must
be met by manual operation of the steering column
shift lever:
a. From reverse to drive position travel, the trans-
mission detent feel must be noted and related to
indicated position on dial.
b.
When in drive and reverse positions, pull lever
rearward (towards steering wheel) and then re-
lease. It must drop back into position with no
restrictions.
NEUTRAL SAFETY SWITCH ADJUSTMENT
The neutral safety switch must be adjusted so that the
car will start in the park or neutral position, but will not
start in the other positions. For replacement refer to
Section 12 of this Manual.
DRAINING AND REFILLING TRANSMISSION
Drain oil immediately after operation before it has had
an opportunity to cool.
To drain oil proceed as follows:
1.
Remove bottom pan attaching screws, pan, and gas-
ket.
2.
Remove oil strainer. Remove "O" ring seal from
pick-up pipe and discard.
3.
Discard strainer if dirty.
4.
Install new "O" ring seal on pick-up pipe and install
strainer and pipe assembly.
5.
Thoroughly clean bottom pan.
6.. Affix new gasket to bottom pan with petroleum jelly.
7.
Install bottom pan with attaching screws and torque
to specifications;
8. If only the pan has been removed, pour approximately
7-1/2 pints of fluid into the transmission. If the
valve body has also been removed use 9-1/2 pints.
After a complete overhaul approximately 19 pints
are required. Be sure container, spout, or funnel is
clean.
9. Start engine and let idle (carburetor off fast idle
step).
Place selector lever in P position and apply
hand brake.
10.
With transmission warm (approximately 150°F), add
fluid to bring level to full mark on indicator.
CAUTION: Do not overfill. Foaming will re-
sult.
CHEVROLET CHASSIS SERVICE MANUAL
CLUTCH AND TRANSMISSIONS 7-41
CAUTION: Use converter holding ToolJ-5384
when lowering transmission or keep rear of
transmission lower than front so as not to lose
converter.
The installation of the transmission is the reverse of
the removal.
TURBO HYDRA-MATIC DIAGNOSIS PROCEDURE
Accurate diagnosis of transmission problems begins
with a thorough understanding of normal transmission
operation. In particular, knowing which units are in-
volved in the various speeds or shifts so that the specific
units or circuits involved in the problem can be isolated
and investigated further. Analytical diagnosis will pro-
tect the technician from come backs and certainly will
improve owner satisfaction.
An important and often overlooked aspect of diagnosis
is finding out specifically what the customer is com-
plaining of. For this purpose a short ride with the cus-
tomer will often prove beneficial. It may be found that
the condition the customer wants corrected is standard
and should not be altered.
The following sequence, based on field experience, pro-
vides the desired information quickly and in most cases
actually corrects the malfunction without requiring the
removal of the transmission. Details of the items listed
in this sequence are covered further in the text.
SEQUENCE FOR TURBO HYDRA-MATIC
DIAGNOSIS PROCEDURE
1.
Check oil level and condition.
2.
Check and correct detent switch.
3.
Check and correct vacuum line and fittings.
4.
Check and correct manual linkage.
OIL LEVEL AND CONDITION CHECK
Always check the oil level before road testing. Oil
must be visible on dip stick prior to operating the ve-
hicle. Erratic shifting, pump noise, or other malfunc-
tions can in some cases be traced to improper oil level.
Oil level should be checked with the selector lever in
the Park (P) position, engine running, and the vehicle on
level pavement.
Fluid level should be to the FULL mark with the trans-
mission at normal operating temperature (170°-190°
F.).
With warm fluid (room temperature), the level should be
at or slightly below the ADD mark.
If oil level was low, refer to Oil Leaks.
The condition of the oil is often an indication of whether
the transmission should be removed from the vehicle, or
to make further tests. When checking oil level, a burned
smell and discoloration indicate burned clutches or bands
and the transmission will have to be removed.
MANUAL LINKAGE
Manual linkage adjustment and the associated neutral
safety switch are important from a safety standpoint
The neutral safety switch should be adjusted so that the
engine will start in the Park and Neutral positions only.
With the selector lever in the Park position, the park-
ing pawl should freely engage and prevent the vehicle
from rolling. The pointer on the indicator quadrant
should line up properly with the range indicators in all
ranges.
OIL LEAKS
Before attempting to correct an oil leak, the actual
source of the leak must be determined. In many cases,
the source of the leak can be deceiving due to "wind flow"
around the engine and transmission.
The suspected area should be wiped clean of all oil be-
fore inspecting for the source of the leak. Red dye is
used in the transmission oil at the assembly plant and
will indicate if the oil leak is from the transmission.
. The use of a "black light"* to identify the oil at the
source of leak is also helpful. Comparing the oil from
the leak to that on the engine or transmission dip stick
(when viewed by black light) will determine the source
of the leak.
Oil leaks around the engine and transmission are gen-
erally carried toward the rear of the car by the air
stream. For example, a transmission "oil filler tube to
case leak" will sometimes appear as a leak at the rear of
the transmission. In determining the source of an oil
leak it is most helpful to keep the engine running.
POSSIBLE POINTS OF OIL LEAKS
• 1. TRANSMISSION OIL PAN LEAK
a. Attaching bolts not correctly torqued.
b.
Improperly installed or damaged pan gasket.
c. Oil pan gasket mounting face not flat.
2.
REAR EXTENSION LEAK
a. Attaching bolts not correctly torqued.
b.
Rear seal assembly — damaged or improperly
installed.
c. Gasket seal — (extension to case) damaged or
improperly installed.
d. Porous casting.
3.
CASE LEAK
a. Filler pipe "O" ring seal damaged or missing;
misposition of filler pipe bracket to engine —
"loading" one side of
"O"
ring.
b.
Modulator assembly "O" ring seal
—
damaged or
improperly installed.
c. Governor cover, gasket and bolts — damaged,
loose; case face leak.
d. Speedo gear
—
"O" ring damaged.
e. Manual shaft seal — damaged, improperly in-
stalled.
f. line pressure tap plug — stripped, shy sealer
compound.
g. Parking pawl shaft cup plug
—
damaged, improp-
erly installed.
h. Vent pipe (refer to Item 5).
i. Porous case.
4.
FRONT END LEAK
a. Front seal - damaged (check converter neck for
nicks,
etc., also for pump bushing moved for-
ward);
garter spring missing from pump to con-
verter seaL
b.
Pump attaching bolts and seals
—
damaged, miss-
ing, bolts loose.
CHEVROLET a
SERVICE
STEERING
9-33
POWER STEERING
INDEX
Page
General Description
. 9-33
Maintenance
and
Adjustments
9-33
Bleeding Hydraulic System
9-33
Fluid Level
. 9-33
Adjustments
. 9-34
Power Steering Gear
. . 9-34
Pump Belt Tension
9-34
Hydraulic System Checks
9-34
Component Replacement
and
Repairs
. 9-35
Power Steering Pump.
. 9-35
Power Steering Gear
9-36
Control Valve
and
Adapter Assembly
9.35
Power Cylinder
9.37
Power Steering Hoses
9.39
GENERAL DESCRIPTION
Two types
of
power steering
are
used
for 1967.
One
is
the conventional linkage type
for
Chevy
n and
Corvette
vehicles
and the
other
is the
integral gear type
for
Chevrolet, Chevelle,
and
Camaro.
For
both types
the
hydraulic pressure
is
provided
by an
engine-driven vane-
type pump.
On
the
Chevy
n and
Corvette linkage type power steer-
ing, hydraulic pressure
is
delivered through
a
hose from
the pump
to a
valve which senses
the
requirement
for
power assistance
and
supplies
the
power cylinder
ac-
cordingly.
The
steering gear used with this power steer-
ing
is the
same basic unit used
on
manually steered
vehicles;
it is
serviced
as
outlined
in the
manual steering
part
of
this section except
for
adjustment, which
is
covered
in the
following pages.
The
steering linkage also
is serviced the same
as
manual counterparts.
The Chevrolet, Chevelle
and
Camaro integral gear type
power steering
has the
hydraulic pressure delivered
from
the
pump through two hoses
to the
steering gear.
In
the power steering gear
the
steering shaft, hydraulic
valve, worm, and rack-piston
nut are all in
line making
a
compact
and
space saving assembly.
All oil
passages
are
internal within
the
gear except
the
pressure
and
return
hoses.
The steering gear
is a
recirculating ball system
in
which steel balls
act as a
rolling thread between
the
steering worm
and
rack-piston
nut. The
rack-piston
nut
is
all one
piece
and is
geared
to the
sector
of
the piston
shaft.
The
valve
is
contained
in the
gear housing elimi-
nating
the
need
of
bolts
or
seals
to
attach
a
separate
valve housing.
The valve
is an
open-center, rotary-type three
way
valve.
The
spool
is
held
in
neutral position by means
of a
torsion
bar. The
spool
is
attached
by
means
of
the stub
shaft
to one end of the
torsion
bar
and
to the
valve body
on
the
other
end.
Twisting
of the
torsion bar allows
the
spool
to
move
in
relation
to the
valve body thereby oper-
ating
the
valve.
MAINTENANCE
AND
ADJUSTMENTS
BLEEDING HYDRAULIC SYSTEM
1.
Fill
oil
reservoir
to
proper level and
let oil
remain
undistrubed
for at
least two minutes.
2.
Start engine
and run
only
for
about
two
seconds.
3.
Add
oil if
necessary.
4.
Repeat above procedure until
oil
level remains
con-
stant after running engine.
5. Raise front
end of
vehicle
so
that wheels
are off
the
ground.
6. Increase engine speed
to
approximately
1500 rpm.
7. Turn
the
wheels
(off
ground) right
and
left, lightly
contacting
the
wheel stops.
8. Add
oil if
necessary.
9. Lower
the car and
turn wheels right and left
on the
ground.
10.
Check
oil
level and refill
as
required.
11.
If oil is
extremely foamy, allow vehicle
to
stand
a
few minutes with engine
off and
repeat above
procedure.
,
a.
Check belt tightness
and
check
for a
bent
or
loose
pulley. (Pulley should
not
wobble with engine
running.)
b.
Check
to
make sure hoses
are not
touching
any
other parts
of the car,
particularly sheet metal.
c. Check
oil
level, filling
to
proper level
if
neces-
sary, following operations
1
through
10.
This
step
and
Step
"D" are
extremely important
as
low
oil
level and/or
air in the oil are the
most
frequent causes
of
objectionable pump noise.
d. Check
the
presence
of air in the oil. If air is
present, attempt
to
bleed system
as
described
in
operations
1
through
10. If it
becomes obvious
that
the
pump will
not
bleed after
a few
trials,
proceed
as
outlined under Hydraulic System
Checks.
FLUID
LEVEL
1.
Check
oil
level
in the
reservoir
by
checking
the dip
stick when
oil is at
operating temperature.
On
Chevelle models equipped with remote reservoir,
the reservoir should
be
maintained approximately
3/4 full when
oil is at
operating temperature.
2.
Fill,
if
necessary,
to
proper level with
GM
Power
Steering Fluid
or, if
this
is not
available, automatic
CHEVROLET CHASSIS SERVICE MANUAL