SECTION 9
STEERING
CONTENTS OF THIS SECTION
Figure Index
CONVENTIONAL STEERING
General Description
Care, Maintenance and Adjustments
Major Service Operations
Troubles and Remedies
POWER STEERING
Description and Operation
Care, Maintenance and Adjustments
Major Service Operations
Power Cylinder
Trouble Diagnosis
Assembly Manual
Figure Index
Fig. 1 - Steering Gear Cross Section Along Wormshaft
Fig. 2 - Steering Gear Cross Section Along Sector Shaft
Fig. 3 - Conventional Steering Linkage
Fig. 4 - Tie Rod End
Fig. 5 - Pitman Arm Attachment to Relay Rod
Fig. 6 - Checking Pull at Wheel Rim
Fig. 7 - Wheel Alignment and High Point Centering Marks
Fig. 8 - Mast Jacket with Eccentricity Gauge in Position
Fig. 9 - Gearshift Lower Control Lever
Fig. 10 - Dash Panel Bracket and Linkage Attachments
Fig. 11 - Indicator Rod Attachment
Fig. 12 - Removing Steering Wheel
Fig. 13 - Removing Pitman Arm from Pitman Shaft
Fig. 14 - Steering Gear Parts Layout
Fig. 15 - Adjusting Lash
Fig. 16 - Removing Sector Shaft from Housing
Fig. 17 - Removing Wormshaft and Ball Nut
Fig. 18 - Replacing Sector Shaft Bushing
Fig. 19 - Removing Wormshaft Bearing Cup
Fig. 20 - Pressing Bearing Cup into Position
Fig. 21 - Filling Ball Circuits in Nut
Fig. 22 - Filling Ball Guides
Fig. 23 - Removing or Replacing Ball Guide
Fig. 24 - Checking Sector Shaft Lash Adjuster End Clearance
Fig. 25 - Installing Sector Shaft Packing and Retainer
Fig. 26 - Mast Jacket and Shifter Tube Assembly - Standard Transmission
Fig. 27 - Exploded View of Mast Jacket and Shifter Tube Assembly
Fig. 28 - Removing Shift Lever and Spring
Fig. 29 - Direction Signal Housing Retaining Screws
Fig. 30 - Removing Locking Plate and Spacer Washer
Fig. 31 - Removing Lever Support Housing
Fig. 32 - Installing Standard Transmission Shifter Tube Assembly to Mast Jacket
Fig. 33 - Tightening Adjusting Ring Screws
Fig. 34 - Direction Signal Housing Adjustment
Fig. 35 - Removing Tie Rod End from Steering Arm
Fig. 36 - Separating Relay Rod from Pitman Arm
Fig. 37 - Conventional Steering Special Tools
Fig. 38 - Hydraulic Steering System
Fig. 39 - Control Valve Adapter Assembly
Fig. 40 - Control Valve Connections
Fig. 41 - Hydraulic Pump and Reservoir Mounted to Generator (8 Cyl. Engine)
Fig. 42 - Checking Fluid Level
Fig. 43 - Drain Fluid from Reservoir
Fig. 44 - Removing Hydraulic Pump
Fig. 45 - Hydraulic Pump Assembly
Fig. 46 - Control Valve Removal
Fig. 47 - Unscrew Control Valve
Fig. 48 - Control Valve Disassembled
Fig. 49 - Control Valve Installation
Fig. 50 - Power Cylinder Installation
Fig. 51 - Power Cylinder
Fig. 52 - Power Steering Special Tools
Conventional Steering
General Description
The regular production steering gear (fig. 1)
and (fig. 2) is the recirculating
ball type with a gear ratio of 20:1. This same gear, which is
also used in conjunction with the power steering unit, provides
for ease of handling by having forces transmitted from worm to
sector gear through ball bearings.
The principal working arrangement of the recirculating ball
type steering gear consists of a "ball nut" connected
to the steering worm and in mesh with the sector gear. Precision
finished helical grooves inside the ball nut match helical grooves
on the worm, and it is in these grooves that the ball bearings
roll as the steering wheel is turned. There are two complete ball
circuits within the ball nut. To keep the balls from running out
of the end of either circuit, the nut is equipped with two tubular
ball guides, each of which deflects the balls away from their
helical path at one end of their travel, guides them diagonally
across the back of the nut, and returns them to their helical
path between the ball nut and the worm at the other end of their
travel.
The balls within the helical path constitute a thread between
the worm and ball nut, so that when the wormshaft is turned, the
nut moves along the worm. At the same time, the balls roll freely
between the worm and the ball nut, circulating within their closed
circuits so that screw motion is obtained with rolling instead
of sliding contact between parts.
Rugged rack teeth in that portion of the ball nut that faces
the sector and the sector gear teeth are cut so as to provide
true gear action between the sector and ball nut when the ball
nut is located at a slight angle. This type of construction provides
a means for backlash adjustment between the ball nut and the sector
by shifting the sector shaft slightly along its own axis. This
is accomplished by means of a convenient thrust screw, known as
a lash adjuster.
The sector teeth are also cut so that when the sector is adjusted
to take out all backlash at the center of travel or straight ahead
position, there will be slight backlash at each end of travel.
Thus snugness of the sector in the rack teeth in a straight ahead
position can be obtained without sacrifice of perfect freedom
at extreme positions, right or left, of the front wheels.
The sector shaft is straddle mounted in antifriction bushings
and a grease seal is provided at the outer end of the shaft. The
worm is integrally welded to the mainshaft and is mounted between
the ball bearings. The bearing at the end of the worm is adjustable
for taking out end play in the wormshaft and for obtaining proper
worm bearing load.
The steering wormshaft passes through a concentric mast jacket
and shifter tube assembly (fig.28)
and (fig. 29), which is
secured to the instrument and dash panels but is not rigidly attached
to the steering gear assembly. The shifter tube is free to rotate
and slide within the mast jacket to transmit control forces from
the shift lever to the transmission. The steering linkage (fig. 3)
is of the relay type, with the pitman arm connected to a relay
rod through an adjustable ball and socket joint. The relay rod
is connected to an idler arm which in turn, is connected to a
support bolted to the frame side rail opposite the steering gear.
Pivoting at the connections at each end of the idler arm is accomplished
in rubber bushings. Connecting the relay rod to the steering arms
are two adjustable tie rods with self adjusting ball and socket
type joints (fig. 4).
Care, Maintenance and Adjustments
Lubrication
Adjustments
Lubrication
The steering gear is filled at the factory with a special all-season
gear lubricant. Seasonal change of this lubricant is unnecessary
and the housing should not be drained. The steering gear lubricant
level should be checked every lubrication period (1000 miles).
Whenever required, additions should be made using a lubricant
which, at low temperatures, is fluid and will not "channel"
or cause hard steering and which will provide satisfactory lubrication
under extreme summer conditions. Steering gear lubricants are
marketed by many oil companies and either "Multi-Purpose"
or "Universal" gear lubricants are satisfactory.
The steering gear linkage should be lubricated every 1000 miles,
with chassis lubricant. Lubrication points and additional information
on the chassis lubricant to be used can be found in Section O-General
Lubrication.
Adjustments Steering Gear
Steering Gear
Pitman Arm to Relay Rod Ball Joint
Steering Wheel Alignment and High Point Centering
Mast Jacket and Steering Gear Alignment
Toe-In Adjustment
Steering Gear
Before any adjustments are made to the steering gear in an attempt
to correct such conditions as shimmy, loose or hard steering and
road shocks, a careful check should be made of front end alignment,
shock absorbers, wheel balance and tire pressure for possible
causes. Correct adjustment of steering gear is very important.
While there are but two adjustments to be made, the following
procedure must be followed step-by-step in the order given.
- Disconnect the steering relay rod from the pitman arm by removing
cotter pin from end of relay rod, then removing end plug, spring,
spring plug and ball seat (fig. 3)
and (fig. 5). Separate relay
rod from pitman arm as shown in Figure 36,
shifting steering linkage as required to obtain separation.
- Loosen the pitman shaft lash adjuster screw lock nut and turn
the adjuster screw (fig. 2)
a few turns in a counterclockwise direction. This removes the
load imposed on the worm bearings by the close meshing of rack
and sector teeth. Turn steering wheel gently in one direction
until stopped by gear, then back away about one turn. CAUTION:
Do not turn steering wheel hard against stops when steering relay
rod is disconnected as damage to ball guides may result.
- Using Tool-544 (fig. 6),
measure pull at rim of wheel which is required to keep wheel in
motion. This should be between 3/8 and pounds. NOTE: When making
this check, it is important that the line of the scale be kept
at right angles to the wheel spoke. If the pull necessary to move
the wheel does not lie between the limits given above, adjustment
of worm bearings is necessary.
- To adjust worm bearings, loosen worm bearing adjuster lock
nut and turn worm bearing adjuster shown in Figure 1
until there is no perceptible end play in worm. Check pull at
wheel rim, readjusting if necessary to obtain proper pull. Tighten
lock nut and recheck pull. If the gear feels "lumpy"
after adjustment of worm bearings, there is probably damage in
the bearings due to severe impact or to improper adjustment and
the gear must be disassembled for replacement of damaged parts.
- After proper adjustment of worm is obtained, and all mounting
bolts securely tightened, adjust lash adjuster screw. First turn
the steering wheel gently from one stop all the way to the other,
carefully counting the total number of turns. Then turn wheel
back exactly half way, to center position. Remove the steering
wheel ornamental cap or horn button and the steering wheel retaining
nut and washer. Note position of mark on end of wormshaft. This
mark should be at top of shaft and aligned with mark on steering
wheel (fig. 7). Turn lash
adjuster screw clockwise to take out all lash in gear teeth, and
tighten lock nut. Check pull at wheel rim with checking scale,
taking highest reading of checking scale as wheel is turned through
center position. This should be between 7/8 and 11/2 pounds. Readjust
if necessary to obtain proper pull. NOTE: If 1 1/2 pounds is
exceeded, turn lash adjuster screw counterclockwise, then come
up on adjustment by turning the adjuster in a clockwise motion.
- Tighten lock nut then recheck pull as it must lie between
specified limits.
- Reassemble relay rod to pitman arm and adjust as outlined
below under Pitman Arm to Relay Rod Ball Joint. Replace steering
wheel assembly.
Pitman Arm to Relay Rod Ball Joint
- Remove cotter pin from end of relay rod, then using a drag
link bit in end plug slot, tighten end plug until springs are
compressed and plugs bottom (fig. 5).
- Back off end plug 3/4 turn plus amount necessary to insert
cotter pin, then insert pin.
Steering Wheel Alignment and High Point Centering
- Remove steering wheel ornamental cap or horn button and wheel
retaining nut. Set front wheels in straight ahead position. This
can be checked by driving vehicle a short distance to determine
steering wheel position at which vehicle follows a straight path.
- With front wheels set straight ahead, check position of mark
on end of wormshaft designating steering gear high point (fig. 7).
This mark should be at the top of the shaft and aligned with mark
on steering wheel. Remove steering wheel, if necessary, and align
mark on wheel with mark on end of wormshaft. See Mast Jacket and
Shifter Tube Removal for a description of the steering wheel removal
operation.
- If gear has been moved off high point when setting wheels
in straight ahead position, loosen adjusting sleeve clamps on
both left and right hand tie rods (fig. 3),
then turn each sleeve an equal amount in the same direction to
bring gear back on high point. CAUTION: Turning the sleeves
an unequal number of turns or in different directions will disturb
the toe-in setting of the wheels.
- Tighten all sleeve clamp bolts. CAUTION: Tie rod clamp
bosses must be below rods to avoid frame interference.
Mast Jacket and Steering Gear Alignment
Mast Jacket-Steering Gear Alignment General Notes
Mast Jacket-Steering Shaft Eccentricity
Steering Shaft Alignment
Mast Jacket-Steering Wheel Clearance
Mast Jacket-Steering Gear Alignment General Notes
Misalignment within the mast jacket assembly may cause steering
or shifting interference (assuming the steering gear itself is
in proper adjustment). A few basic causes of such interference
together with suggested checks and adjustments are listed below.
- Steering shaft not aligned with mast jacket and shifter
tube assembly-Check and align steering shaft as described
below under Mast Jacket-Steering Shaft Eccentricity. Extreme cases
of misalignment, preventing steering shaft from being centered
in instrument panel opening without bending shaft, may be corrected
as described under Steering Shaft Alignment.
- Interference between steering wheel and top of direction
signal housing-Check and adjust as described under Mast Jacket-Steering
Wheel Clearance.
- Damaged steering shaft, snifter tube or components within
the mast jacket-See Major Service Operations.
Mast Jacket-Steering Shaft Eccentricity
- With the clamp bolt (fig. 8)
and two bolts securing mast jacket bracket to the toe board loosened,
insert Tool 6424 between jacket and steering shaft so that the
tool handle bisects the center line of the keyway (fig. 8).
Be sure to insert the correct side of the tool ( "STD"
or "PG") depending upon transmission involved.
- Shift the mast jacket as required until the tool is held firmly
between the jacket and steering shaft, then tighten the clamp
bolt and two mast jacket mounting bracket bolts in that order.
- To check that the mast jacket did not shift while tightening
the bolts, again insert the tool between the mast jacket and steering
shaft with the tool handle coincident with the centerline of the
keyway. The fit should be snug, otherwise repeat the adjustment.
- Slip shift rods (fig. 8)
through swivel nuts but do not tighten. Fabricate improvised shift
lever alignment gauge from a hacksaw blade using the dimensions
furnished in Figure 9, then
perform shift lever alignment as follows:
- Insert improvised tool in adjusting ring keyway at bottom
of mast jacket through first and reverse, and second and high
shift levers.
- Move both shift rods until transmission is in neutral. Neutral
detents must both be engaged to make this adjustment correctly.
To check, start engine with clutch disengaged, and release clutch
slowly.
- Tighten swivel nuts (fig. 8)
and remove aligning tool while exerting light downward pressure
on lower levers.
Steering Shaft Alignment
- Loosen the steering gear to frame bolts and the bolts securing
the lower mast jacket bracket to the jacket and dash panel (fig. 10).
- Install Tool 6424 between steering shaft and adjusting ring
to center shaft in mast jacket as described under Mast Jacket-Steering
Shaft Concentricity.
- Shim between steering gear and frame at bolt holes to maintain
this alignment and tighten gear-to-frame and mast jacket bracket
bolts. NOTE: The bracket upper clamp bolt should be tightened
before the lower mast jacket bracket bolts.
Mast Jacket-Steering Wheel Clearance
- Measure gap between top edge of direction signal housing and
bottom outer edge of steering wheel, clearance should be 1/16"
- 5/64".
- To adjust to proper clearance:
- Remove lower mast jacket cover.
- Loosen nuts attaching clamp assembly to support assembly just
enough to permit mast jacket to be removed, without rotating,
along steering shaft.
- Locate mast jacket to obtain 1/16" clearance at steering
wheel and tighten screws at dash panel bracket.
- Install lower cover.
If not within specified range, loosen screw through hole in lever
support housing on adjusting washer. With the screwdriver move
the adjusting washer up or down until proper end play is reached.
Tighten down on screw. Toe-In Adjustment A procedure for adjusting
the steering linkage for proper toe-in setting is described in
Section 3.
Major Service Operations
Mast Jacket and Shifter Tube Removal
Steering Gear
Mast Jacket and Shifter Tube Overhaul
Steering Gear Installation
Mast Jacket and Shifter Tube Installation
Steering Linkage Overhaul
Idler Arm
Mast Jacket and Shifter Tube Removal
Removal
- Disconnect all electrical connections and remove the back-up
light switch, where installed, from mast jacket. NOTE: A combination
back-up light neutral safety switch is installed on Powerglide
and Turboglide models.
- Remove two rubber cover upper fasteners from inside of dash
panel at mast jacket opening.
- Pry off horn button or ornamental cap and remove horn mechanism.
- Remove lower cover retaining screw and washer and remove lower
cover.
- On Powerglide and Turboglide models only:
- Disconnect ends of indicator rod from indicator lever and
shifter tube and remove rod (fig. 11).
- Remove neutral safety switch.
- Remove transmission control selector plate shown in inset
of Figure 9.
- Remove steering wheel nut and washer from end of steering
gear shaft, then using Tool 2927, thread puller anchor screws
into threaded holes provided in steering wheel hub. Turn center
screw down against centering adapter (fig. 12)
and force wheel from steering shaft. Remove spring and spring
seat from end of steering shaft.
- Remove nut, washers and clamp bolt from dash panel attaching
bracket (fig. 9).
- Disconnect transmission control linkage from shifter levers
at swivels. Remove swivels from shifter levers.
- Remove nuts and washers retaining clamp to bottom of instrument
panel and remove clamp and rubber shims.
- From inside vehicle pull mast jacket assembly carefully off
steering shaft, rotating as necessary to clear dash clamp. Work
shifter levers through dash seal by stretching the seal to clear
levers. NOTE: It may be necessary to pry dash panel clamp apart
to free the most jacket.
Steering Gear
Removal
Steering Gear Overhaul
Removal
- With mast jacket assembly removed, disconnect pitman arm from
pitman shaft using Tool 5504 (fig. 13).
- On Power Steering models remove the generator-to-support and
generator brace bolts and move generator and pump assembly out
of position (without disconnecting hoses) to obtain clearance
to remove steering gear assembly.
- Remove nuts and lockwashers from steering gear to frame bolts
and remove bolts, shims where installed and steering gear.
- Remove the four felt seals from mainshaft of steering gear
assembly.
Steering Gear Overhaul
Disassembly
Ball Nut Disassembly
Inspection
Repairs
Ball Nut Assembly
Steering Gear Assembly
Adjustment on Bench
Disassembly
As with any ball bearing unit the steering gear parts must be
kept free of dirt. Clean paper or rags should be spread on the
bench before starting disassembly of the steering gear. Refer
to Figure 14.
- Loosen lock nut on end of sector shaft and turn the lash adjuster
a few turns counterclockwise (fig. 15).
This will remove the load from the worm bearings caused by the
close meshing of the rack and sector teeth.
- Loosen the lock nut on the worm bearing adjuster shown in
Figure 15 and turn the adjuster
counterclockwise a few turns.
- Place a pan under the assembly to catch the lubricant and
remove the three bolts and washers attaching side cover to housing.
- Pull the side cover with the sector and shaft from the housing
(fig. 16). NOTE: If the
sector does not clear the opening in the housing easily, turn
the wormshaft by hand until the sector will pass through the opening
in the housing.
- Remove the worm bearing adjuster, adjuster lock nut and lower
ball bearing from housing.
- Draw wormshaft and nut assembly from housing (fig. 17).
Remove upper ball bearing. CAUTION: Use care that the ball
nut does not run down to either end of the worm. Damage will be
done to the ends of the ball guides if the nut is allowed to rotate
until stopped at the end of the worm.
- Remove lock nut from lash adjuster and unscrew adjuster from
side cover by turning adjuster clockwise. Slide adjuster and shim
out of slot in end of sector shaft.
- Remove sector shaft packing retainer; then remove and discard
sector shaft packing.
Ball Nut Disassembly
As a rule, disassembly of the ball bearing nut will not be necessary
if it is perfectly free with no indication of binding or tightness
when rotated on the worm. However, if there is any indication
of binding or tightness, the unit should be disassembled, cleaned
and inspected as follows:
- Remove screw and clamp retaining ball guides in nut. Draw
guides out of nut (fig. 23).
- Turn the nut upside down and rotate the wormshaft back and
forth until all the balls have dropped out of the nut into a clean
pan. With the balls removed the nut can be pulled endwise off
the worm.
Inspection
With the steering gear completely disassembled (fig. 14)
wash all parts in cleaning solvent. Dry them thoroughly with clean
rags. With a magnifying glass inspect the ball bearings, bearing
cups, worm and nut grooves and the surface of all balls for signs
of indentation. Also check for any signs of chipping or breakdown
of the surface.
Any parts that show signs of damage should be replaced. Balls
must be replaced with genuine Chevrolet parts made according to
specifications for this steering gear. No non-genuine balls should
be used regardless of grade or quality.
Inspect wormshaft seal for defects.
Inspect the sector shaft for wear and check the fit of the shaft
in the housing bushings.
Inspect the fit of the pilot on the end of the sector shaft in
its bushing in the side cover. If this bushing is worn, a new
side cover and bushing assembly should be installed.
Check ball guides for damage at ends where they deflect or pick
the balls from their helical path. Any damaged guides should be
replaced.
Check steering gear wormshaft assembly for bent or damaged shaft.
Repairs
Sector Shaft Bushing Replacement
Wormshaft Seal Replacement
Side Cover Bushing Replacement
Sector Shaft Packing Replacement
Wormshaft Bearing Cup Replacement
Sector Shaft Bushing Replacement
- Support steering gear housing in an arbor press and press
both sector shaft bushings from housing with Tool 1614, inserted
from lower end of housing as shown (fig. 18).
- Press new bushings into position from each end using the same
sector shaft bushing driver as used for removal. NOTE: Service
bushings are diamond bored to size and require no further reaming.
Wormshaft Seal Replacement
If the wormshaft seal indicates need of replacement, it should
be removed and a new seal pressed into position in the housing.
Tool 5813 may be used to install seal.
Side Cover Bushing Replacement
The entire side cover assembly, including bushing is serviced
as a unit and should be replaced where it is desired to replace
the bushing.
Sector Shaft Packing Replacement
The sector shaft packing must be replaced each time a defective
packing is indicated or the steering gear is disassembled. This
operation is described under Steering Gear Assembly.
Wormshaft Bearing Cup Replacement
- Remove wormshaft bearing cups using Tool 5822 with Tool 2654
(fig. 19).
- Press new bearing cups into position using Tool 5755 (fig. 20).
Ball Nut Assembly
- Place the wormshaft flat on the bench and slip the nut over
the worm with the ball guide holes up and the shallow end of the
rack teeth to the left from the steering wheel position. Align
the grooves in the worm and nut by sighting through the ball guide
holes.
- Count 27 balls into a suitable container. This is the proper
number of balls for one circuit. Drop counted balls from container
into one of the guide holes while turning the worm gradually away
from that hole. Continue until ball circuit is full from bottom
of one guide hole to bottom of the other or until stopped by reaching
the end of the worm. NOTE: In cases where the balls are stopped
by the end of the worm, hold down those balls already dropped
into the nut with the blunt end of a clean rod or punch (fig. 22) and turn the worm in the reverse direction a few turns. The filling
of the circuit can then be continued. It may be necessary to work
the worm back and forth, holding the balls down first in one hole
then the other, to close up the spaces between the balls and fill
the circuit completely and solidly.
- Lay one-half of the ball guide, groove up, on the bench and
place the remaining balls from the count container in it (fig. 21).
- Close this half of guide with the other half. Hold the two
halves together and plug each open end with vaseline so balls
will not drop out while installing guide.
- Push the guide into the guide holes of the nut (fig. 23).
This completes one circuit of balls. If the guide does not push
all the way down easily, tap it lightly into place with the wooden
handle of a screwdriver.
- Fill second ball circuit in the same manner.
- Assemble the ball guide clamp to the nut, being sure to use
a lockwasher under the clamp screw, then tighten the screw securely.
Check the assembly by rotating the nut on the worm to see that
it moves freely. Do not rotate the nut to the end of the worm
threads as this may damage the ball guides. If there is any "stickiness"
in the motion of the nut, some slight damage to the ends of the
ball guides or to other gear components may have been overlooked.
Steering Gear Assembly
After a major service overhaul where all of the original factory
installed lubricant has been washed out of the steering gear assembly,
the threads of the adjuster, side cover bolts and lash adjuster
should be coated with a suitable nondrying, oil resistant sealing
compound such as Permatex No. 2. This is to prevent leakage of
gear lubricant from the steering gear assembly. The compound should
not be applied to female threads and extreme care should be exercised
in applying this compound to the bearing adjuster, as the compound
must be kept away from the wormshaft bearing. Also apply grease
to the worm bearings, pitman shaft bushings, and ball nut teeth.
- With wormshaft seal, bushings and bearing cups installed and
ball nut assembly installed on wormshaft, slip upper ball bearing
over wormshaft and insert wormshaft and nut assembly into housing,
feeding end of shaft through upper ball bearing cup and seal (fig. 17).
- Place ball bearing in adjuster cup and install adjuster and
lock nut in lower end of housing.
- Assemble the lash adjuster with shim in the slot in the end
of sector shaft. Check the end clearance which should not be greater
than .002" (fig. 24).
For the purpose of adjusting this end clearance, a steering gear
lash adjuster shim unit Part Number 605142 is available. It contains
four shims-.063", .065", .067" and .069" thick.
- After lash adjuster end clearance has been adjusted, start
sector shaft pilot into bushing in side cover. Then, using a screwdriver
through the hole in cover, turn lash adjuster in a counterclockwise
direction to pull sector shaft pilot into its bushing as far as
it will go.
- Rotate wormshaft by hand until ball nut is about in the center
of travel. This is to make sure that the rack and sector will
engage properly, with center tooth of the sector entering center
tooth space of the nut.
- Place a new gasket on side cover, then push side cover assembly
including sector shaft into place (fig. 16).
After making sure there is some lash between rack and sector teeth,
assemble and tighten side cover bolts.
- Soak new sector shaft packing in engine oil to lubricate it;
then install it in packing retainer. Use a new retainer if necessary.
- Place Tool 5787 over end of sector shaft, then slide packing
and retainer over protector and press into position with Tool
5813 (fig. 25).
Adjustment on Bench
- Tighten the worm bearing adjuster until all wormshaft end
play has been removed. Then tighten the lock nut.
- Install the steering wheel on the wormshaft temporarily. Carefully
turn the steering wheel all the way in one direction and then
turn back about one turn.
- Using Tool 544 at right angles to one spoke at wheel rim,
measure the pull required to keep the wheel in motion. This should
be between 3/8 and 5/8 pounds. If necessary, adjust the worm bearing
adjuster until proper pull is obtained.
- Turn the steering wheel from one stop all the way to the other,
counting the number of turns. Then turn the wheel back exactly
half the number of turns to the center position and mark the wheel
at the top or bottom.
- Turn the sector lash adjuster screw (fig. 15)
clockwise to remove all lash between rack and sector teeth. Tighten
the lock nut. NOTE: Be sure adjustment is not changed while
tightening the lock nut.
- Using Tool 544 check pull at rim of steering wheel. Take highest
reading on scale as wheel is pulled through center position. This
should be between 7/8 and 1 1/2 pounds.
- If necessary, readjust lash adjuster screw to obtain proper
pull. Tighten lock nut to 10-15 ft. lbs. torque and again check
pull.
- Fill the assembly with steering gear lubricant to the level
of the filler plug hole and replace filler plug.
Mast Jacket and Shifter Tube Overhaul
Disassembly
Cleaning and Inspection
Assembly
Disassembly
Refer to figures 26 and
figure 27.
- Slide rubber grommet back from lever support housing, drive
out shift lever pin and remove shift lever and anti-rattle spring
(fig. 28).
- Remove the three direction signal housing retaining screws
indicated by arrows in Figure 29
and remove direction signal housing. It will be necessary to shift
position of direction signal controls to gain access to the retaining
screws. CAUTION: Withdraw housing with care to avoid damage
to horn and direction signal wiring connections.
- Remove locking plate and spacer washer (fig. 30).
- Remove lever support housing (fig. 31).
- Remove screw attaching adjusting washer from mast jacket.
- Reverse mast jacket and loosen retaining bolts on adjusting
ring while holding ring to release compression of spring slowly.
Remove adjusting ring. On Powerglide or Turboglide models remove
spring from end of shifter tube.
- On standard transmission models remove the two shifter levers
and spacer from end of shifter tube assembly.
- Remove shifter tube assembly by pulling it out from end of
mast jacket.
Cleaning and Inspection
- Clean all metal parts in cleaning solvent and dry them with
compressed air.
- Inspect transmission control lever housing for burrs, scratches
and wear. NOTE: The clearance is critical between the shifter
tube assembly and the lever support housing. There must be no
interference between these two working parts and any excessive
clearance must be corrected by the installation of new parts.
- Inspect steering shaft bearing in direction signal housing.
The bearing may be replaced by prying out of position and installing
a new bearing and horn wire assembly.
- Inspect direction signal wiring connections and switch.
- Check direction signal lever for smoothness of operation and
freedom from bind. Replace defective parts.
- Inspect shifter levers and shifter tube assembly for worn
or damaged parts. The shifter tube assembly must be replaced as
a unit in event of worn or damaged component parts. NOTE: The
shifter tube assembly on standard transmission models consists
of the tube, spring, keys, felt seal and washers. On Powerglide
models the shifter tube consists of an integral shifter lever
and a felt seal.
- On Powerglide models inspect indicator rod clip to see that
it is anchored in the two holes in shifter tube and firmly clipped
to the tube.
Assembly
- Generously lubriplate all keys and small diameter ends of
the shifter tube.
- Insert shifter tube into mast jacket from lower end of mast
jacket and install return spring to lower end of shifter tube
and slide against shifter lever Fig. 32.
- On standard transmission models only:
- Lubriplate and install second and third shifter lever on shifter
tube. A "U" is stamped on this lever for identification.
- Lubriplate and install first and reverse lever on shifter
tube. An "L" is stamped on this lever for identification
purposes.
- Lubriplate and place adjusting ring in lower end of mast jacket
over shifter tube.
- Apply sufficient load on the adjusting ring parallel to the
centerline of the shifter tube. Tighten the three screws holding
adjusting ring to bottom of mast jacket. This will maintain a
tight fit between levers and adjusting ring.
- On Powerglide models, push adjusting ring into mast jacket
bolt slots as far as possible to compress the return spring, then
tighten the three adjusting ring bolts Fig. 33.
- Reverse mast jacket and working from the top end install adjusting
washer (fig. 27).
- Lubriplate inner diameter of lever support housing and install
housing, fitting keyway in housing over key on shifter tube (fig. 31).
- Carefully feed direction signal and horn wires through lever
support housing and along the mast jacket.
- With lever support housing installed, install locking plate
in bayonet slots in mast jacket. Place direction signal housing
in normally installed position on mast jacket to check alignment
of attaching screw holes in housing and locking plate.
- Install direction signal housing and retaining screws, locating
key in housing in mast jacket keyway.
- Check end play between lever support housing and direction
signal housing. End play should be .004"-.009". If not
within specified range, loosen screw (through hole in lever support
housing) on adjusting washer Fig. 34.
With the screwdriver move the adjustingwasher up or down until proper
end play is reached. Tighten downon screw.
- Lubriplate the anti-rattle spring and place it on end of shift
lever, then position shift lever in housing and install pin. Slide
rubber grommet into position over pin and against housing.
- Install wiring clips over wires on side of mast jacket.
Steering Gear Installation
- Place the four felt seals over mainshaft and slide against
steering gear housing.
- Insert end of mainshaft through dash panel opening and position
steering gear assembly on frame. Install bolts, lockwashers and
nuts through bracket. NOTE: Shims may be placed between steering
gear and frame as required to center steering shaft in instrument
panel opening.
- Connect pitman arm to pitman shaft.
- Install mast jacket and shifter tube assembly as described
below. Also install generator and pump assembly on Power Steering
models.
Mast Jacket and Shifter Tube Installation
- Slip assembled mast jacket over steering shaft and feed it
downward to approximate location, rotating as required to provide
clearance for the shifter levers and other projections at dash
panel and dash panel clamp. The rubber seal at the dash panel
opening must be stretched to clear shifter levers.
- Position upper mast jacket clamp with upper and lower rubber
shims installed over retaining bolts so that key in clamp engages keyway in bottom
of mast jacket and clamp is centered in instrument panel opening.
Install clamp washers and nuts and tighten nuts just enough to
hold key in keyway (to prevent rotation of mast jacket) and still
permit mast jacket to be moved along steering shaft.
- Install steering wheel, horn mechanism and horn button or
ornamental cap, aligning steering wheel with mark on end of steering
shaft.
- Grasp mast jacket assembly and pull assembly back along steering
shaft toward steering wheel. Locate assembly 1/16" from steering
wheel by placing feeler gauge or 1/16" shim stock between
top edge of direction signal housing and bottom outer edge of
steering wheel. With assembly located in this position, tighten
clamp nuts below instrument panel.
- Install dash panel attaching bracket clamp bolt, washers and
nut.
- With shift lever in neutral, check to see if steering gear
shaft is centered in the mast jacket assembly. This may be done
by inserting Tool 6424 between steering shaft and inner diameter
of adjusting ring as described previously under Mast Jacket-Steering
Shaft Eccentricity.
- If shaft is not centered, loosen the dash panel bracket clamp
bolt and the two lower bracket retaining bolts. With Tool 6424,
securely tighten first the upper clamp bolt, then the two lower
bracket bolts.
- Connect transmission control rods to shifter levers. On automatic
transmission models install the transmission control selector
plate shown in the inset of Figure 9.
- With shift lever in Neutral position install back-up light
and neutral safety switch where applicable.
- Position rubber seal and cover to dash panel and install upper
fasteners.
- Connect horn wire and, where applicable, direction signal,
back-up light and neutral safety switch wiring, by connecting
matching colors at the connectors. CAUTION: Where equipped
with combination back-up light neutral safety switch, it is imperative
that wires -be connected to proper switch terminals.
- After completing installation, check steering and shifting
for bind. Also check neutral safety and back-up light switch,
where applicable for proper operation. It may be necessary to
loosen the neutral safety switch attaching screws and shift position
of switch to obtain proper operation.
Steering Linkage Overhaul
Tie Rods
Relay Rod
Tie Rods
Tie Rod General Notes
Removal
Installation
Tie Rod General Notes
There are two tie rods used on all model passenger cars. Each
tie rod is of three piece construction, consisting of the tie
rod and two tie rod end assemblies. The ends are threaded into
the rod and locked with clamps. Right and left hand threads are
provided to facilitate toe-in adjustment and steering gear centering.
The tie rod ends used (fig. 4)
are self adjusting for wear and require no attention in service
other than periodic lubrication and occasional inspection to see
that ball studs are tight. Replacement of tie rod ends should
be made when excessive up and down motion is evident or if any
lost motion or end play at ball end of stud exists.
Removal
- Remove cotter pins from ball studs and remove castellated
nuts.
- To remove outer ball stud, tap on steering arm at tie rod
end with a hammer while using a heavy hammer or similar tool as
a backing (fig. 35). If
necessary pull downward on tie rod to remove from steering arm.
- Remove inner ball stud from relay rod, using same procedure
as described in Step 2.
- To remove tie rod ends from tie rods, loosen clamp bolts and
unscrew end assemblies.
Installation
- If tie rod ends were removed, install ends on tie rod making
sure both ends are threaded an equal distance into the tie rod.
- Make sure that threads on ball studs and in ball stud nuts
are perfectly clean and smooth. Install neoprene seals on ball
studs. NOTE: If threads are not clean and smooth, ball studs
may turn in tie rod ends when attempting to tighten nut.
- Install ball studs in steering arms and relay rod.
- Install ball stud nuts, tighten securely and install cotter
pins. Lubricate tie rod ends.
- Adjust toe-in as described in Section 3. NOTE: Before locking
clamp bolts on tie rods, make sure that the tie rod ends are in
alignment with their ball studs (each ball joint is in the center
of its travel). If the tie rod is not in alignment with the studs,
binding will result. Also, tie rod clamp bosses must be below
tie rods to avoid frame interference.
Relay Rod
Removal
Cleaning, Inspection and Repairs
Installation
Removal
- Remove inner ends of tie rods from relay rod as described
under Tie Rod-Removal.
- Remove cotter pin from end of relay rod at pitman arm ball
stud attachment.
- Using a drag link bit, remove end plug from socket and remove
spring plug and outer ball seat from relay rod (fig. 5).
- Detach relay rod from pitman arm (fig. 36)
and remove inner ball seat, plug and spring from relay rod (fig. 5).
Shift steering linkage as required to free pitman arm from relay
rod.
- Remove cover and seal from pitman arm.
- Remove cotter pin and nut from relay rod end of idler arm.
- Remove relay rod from vehicle.
Cleaning, Inspection and Repairs
Cleaning and Inspection
Remove accumulated grease and dirt from assembly and inspect for
damage or excessive wear.
Repairs
Pitman arm ball seats may be replaced if inspection shows necessity.
The Idler Arm to Relay Rod bushing may be replaced by pressing
out old bushing and pressing in new bushing. Note side of rod
which bushing shoulder is against and install new bushing in same
manner.
Installation
- With wheels in a straight ahead position, place relay rod
over idler arm, then install and tighten nut to 70 ft. lbs. Advance
nut just enough to align castellation with cotter pin hole and
install pin.
- Install new seal and cover over ball at end of pitman arm.
- Install inner spring, plug and seat to pitman arm end of relay
rod.
- Raise end of rod and install on pitman arm.
- Install outer ball seat, spring, plug and end plug.
- Tighten end plug until springs are compressed and plugs bottom,
then back off 3/4 turn plus amount necessary to insert cotter
pin. Insert cotter pin to lock adjustment.
- Install tie rod ends to relay rod as previously described
under Tie Rods.
- Lubricate tie rod ends and pitman arm to relay rod ball joint.
- Adjust toe-in (see Section 3) and align steering wheel as
described previously in this section under Steering Wheel Alignment
and High Point Centering.
Idler Arm Removal
- Removal
- Cleaning and Inspection
- Repairs
- Installation
Removal
- Remove cotter pins and nuts from ends of idler arm and remove
relay rod from idler arm.
- Remove idler arm from idler arm bracket.
Cleaning and Inspection
Remove accumulated grease and dirt from assembly and inspect for
damage or excessive wear.
Repairs
If inspection shows a faulty bushing, press out old bushing and
press in new bushing.
Installation
- Position idler arm over idler arm bracket and install nut
but do not tighten.
- Install relay rod to idler arm and install nut but do not
tighten.
- With wheels in straight ahead position and steering gear on
high point, tighten idler arm to bracket nut and relay rod to
idler arm nut to 70 ft. lbs. Advance both nuts just enough to
align castellations with cotter pin holes and install pins.
Troubles and Remedies
Symptom and Probable
Probable Remedy
Cause Hard Steering
a. Lack of lubrication.
a. Lubricate steering gear, tie rod ends, steering relay rod
ball joints and steering knuckle joints.
b. Pitman shaft to relay rod ball joint too tight.
b. Readjust ball joint.
c. Underinflated tires.
c. Inflate tires to recommended pressure.
d. Improper adjustment.
d. Adjust according to instruction.
e. Interference between steering shaft and mast jacket assembly
caused by misalignment, bent steering
shaft or damaged parts within the mast jacket assembly.
e. Adjust or replace parts as required.
Loose Steering
a. Improper adjustments.
a. Adjust according to instructions.
b. Loose pitman shaft to relay rod ball joint.
b. Adjust ball joint.
c. Worn steering knuckle ball joints.
c. Replace steering knuckle ball joints.
d. Worn pitman shaft bushings.
d. Replace bushings.
SPECIFICATIONS
Gear Ratio - 20:1
Type - Recirculating Ball
Number Balls Used - 54
Lash Adjustment or High Point - 7/8 to 1 1/2 lbs.
End Clearance-Lash Adjuster to Sector Slot - 002" Max.
Worm Bearing Adjustment - 3/8 to 5/8 lbs. to keep wheel in motion
Power Steering System
General Description
Power Steering Generator
Recirculating Ball
Hydraulic Pump and Reservoir
Hydraulic Steering Maintenance
General Description
Chevrolet Power Steering equipment on passenger cars, consists
of a recirculating ball type steering gear and linkage to which
a hydraulic power mechanism has been added as part of the steering
linkage. The hydraulic mechanism furnishes additional power to
ASSIST the manual operation so that the turning effort at the
steering wheel is greatly reduced.
The power steering equipment is designed to reduce steering effort
but not to remove the so called "feel" of steering.
With Chevrolet Power Steering, the hydraulic assistance is zero
up to a pull of about 3 pounds at the rim of the steering wheel
and the steering of the car is entirely normal. At this 3 pound
load, the hydraulic system starts to assist the driver's effort
and from 3 to 8 pounds pull, the input effort is proportional
to the force necessary to turn the front wheels. The 8 pound load
is sufficient to turn the front wheels with the car standing still
which means the hydraulic system is doing about 80% of the work
of steering.
In addition to assisting the driver in steering the car, Power
Steering greatly reduces the effort required in parking. The oil
filled hydraulic cylinder absorbs road shocks when driving over
rough roads, railroad tracks, etc. This permits the wheel in the
driver's hand to remain steady, reduces driver "fatigue"
and permits many miles of driving without tiring.
Power Steering Generator
A special generator is used with new cars equipped with power
steering. On these models, the power steering pump is mounted
on the commutator end frame and is driven by the splined armature
shaft which extends from the generator.
Generators of this type use ball bearings at both end frames and
all parts have close tolerances in order to provide for the proper
alignment between the generator and the power steering pump. Improper
alignment of the generator and power steering pump may cause a
noisy generator and pump assembly. Improper alignment may result
from careless handling of the generator assembly (resulting in
deformed parts), worn bearings, careless assembly of the pump
to the generator, or other similar items.
Power steering pumps are sealed to prevent leakage of fluid. One
of the seals used for this purpose mounts on the polished surface
(1/2" diameter) of the generator shaft extension. Damage
to this surface (which is machined to very close limits) or damage
to the seals during re assembly of the pump to the generator may
result in loss of fluid from the power steering pump. Lubrication
required on the generator is the same as for the standard installation.
Recirculating Ball
Hydraulic Steering Mechanism
Hydraulic Control Valve
The steering gear used with Power Steering is the same recirculating
ball type as used on regular production jobs.
Hydraulic Steering Mechanism
The hydraulic power steering mechanism consists of an engine driven
oil pump delivering oil at a pressure of 750 pounds per square
inch, an oil reservoir, a double-acting hydraulic power cylinder,
and a control valve (fig. 38).
The hydraulic power cylinder assembly is mounted on a bracket
on the relay rod at one end and to another bracket on the frame
of the vehicle.
Hydraulic Control Valve
The hydraulic control valve is attached to the left end of the
steering relay rod (fig. 38)
and is operated by the pitman arm in the following manner:
The hydraulic arm ball stud is retained in a sliding hearing sleeve
inside the steering linkage tube. Protruding from the ball seat
adjusting nut is a long valve shaft (fig. 39).
The spool of the control valve is attached to this shaft so that
any movement of the sliding bearing sleeve is transmitted to the
control valve spool. The spool is restricted to a movement of
.050" travel to the right and left from its centered position
by a spacer between the control valve housing and adapter housing
and by the correct adjustment of the ball stud adjuster. A steel
pin (fig. 39) locks the
ball stud adjuster to the sliding bearing sleeve. The spool assembly
has two annular grooves which connect three annular passages inside
the valve housing. The valve spool member is centered and restrained
from actuation on the valve shaft by a pre-loaded spring. It is
necessary to overcome the pre-load of the spring before the valve
spool can be moved in either direction. When there is sufficient
resistance to rotation of the steering arm developed at the front
wheels, continued turning of the steering wheel will result in
an axial movement of the valve shaft, thus overcoming the pre-load
of the spring. This axial movement is due to the hook-up from
the pitman arm (fig. 40).
When the valve spool assembly is in centered position, the oil
from the hydraulic pump flows through the center passage of the
valve body, through the annular grooves in the spool to the annular
passages in the housing and then back to the pump.
When axial movement of the spools occurs with a three pound effort
on the steering wheel, the direct circuit of the pump is interrupted
by shutting off both of the direct return passages. The oil is
then forced to travel to one end of the hydraulic power cylinder
to move the cylinder axially on the piston shaft. At the same
time the opposite end of the power cylinder is open to the pump
return line and permits oil at this end to return through the
control valve to the pump reservoir.
Hydraulic Pump and Reservoir
The oil pump, a vane type pump, is mounted on the engine in position
to be driven by a splined extension of the generator armature
shaft (fig. 41).
The pump houses a serrated driving hub or rotor in which ten vanes
slide radically outward to contact the hardened and ground inside
surface of a cam ring. As the shaft and rotor rotate, centrifugal
force and fluid pressure against the inner ends causes the vanes
to follow the cam contour of the ring. The contour of the ring
is so shaped that two opposing pumping chambers are formed. In
each pumping chamber, the increasing and decreasing pockets formed
between the rotor, vanes, and ring, propel the oil from the entrance
to the exit ports of the pump.
The pump contains a combination overload relief valve, which is
set to open at 750-P.S.I. at 170F and a flow control valve which
recirculates oil within the pump as required to regulate the output
volume between 1.1 gal. per minute at idling speed to 1.8 gal.
per minute at approximately 3600 RPM.
The reservoir encloses the pump cover assy. (fig. 41)
and provides a reserve supply of oil to assure complete filling
of the hydraulic system. An air chamber in the upper part of the
reservoir and a vented cover attachment provide for the escape
of any air that may be introduced into the system.
Hydraulic Steering Maintenance
Hydraulic Steering Maintenance can be covered in three categories
that generally will include any complaint on the operation of
the unit. These three categories, leaks, noise and hard steering,
if properly handled will correct the majority of complaints that
may be encountered regarding the unit's operations.
Care, Maintenance and Adjustments
Care, Maintenance and Adjustments
Leaks
Noise
Hard Steering
Fluid Level
Bleeding Hydraulic System
Pump Belt Tension
Checking Pump Pressure
Steering Wheel Alignment
Care, Maintenance and Adjustments
Cleanliness is a highly important factor in the service of the
power steering unit. If dirt enters the hydraulic system it will
cause noise, leaks or improper operation. When working on a power
steering unit be sure to completely clean the outside before disassembly.
Be sure the bench is free of dirt, then lay the parts on clean
paper. Careful thought to cleanliness while disassembling and
reassembling the power unit will prevent having dissatisified
owners and a job that must be done over.
Leaks
If the complaint is oil loss in the power steering unit, the following
steps should be performed. First, wipe the complete unit dry.
This includes the pump, hoses, power cylinder, and control valve.
Then fill the reservoir, start the engine, operate the steering
unit and observe where the leak occurs. The position of the leak
will then give an indication of the cause. A possible place for
leakage would be at the pump, involving either the reservoir to
pump body seal or the pump drive shaft oil seal. In the case of
pump leakage the repair is fairly simple requiring very little
time to replace the seals. Other leaks may require removal of
the unit from the car and more involved service. Improperly installed
seals is a major cause of leaks. Damage to "O" ring
seals will cause leaks if the housings have sharp edges which
cut the "O" rings. Sharp edges should be removed with
a fine stone and new seals installed.
Noise
When the complaint is excessive noise it is sometimes hard to
isolate the sound. Following is a quick check to determine whether
or not the steering unit is at fault. Disconnect the pump drive
belt and operate the car. If the noise is no longer present then
make the power steering unit the next check.
CAUTION: Do not operate the engine too long with the belt
disconnected since the water pump is also driven by this belt
and the engine may become overheated.
Another good thing to remember is never diagnose a power steering
complaint without first checking fluid level and drive belt tension.
Either may cause noises and malfunctions which could conceivably
be blamed on the steering unit. When checking fluid level, be
sure bubbles are not present in the fluid. If bubbles are found,
the bleeding procedure outlined under "Bleeding Hydraulic
System" should be performed.
Another cause of noise in the pump can be a sticky valve which
will produce a buzzing sound. This can be determined by checking
for excessive pump pressure with oil pressure gauge, Tool 5176,
outlined under "Checking Pump Pressure."
Obstructions in the hydraulic system will also cause a noise.
For instance, a slight burr on the edge of one of the valve spool
lands or a hose restriction will cause a noise on turns. Removal
of the burr with a fine stone or replacement of the hose will
be necessary for correction.
If belt noise, possibly accompanied by a knock or steering wheel
oscillation, is present on extreme turns, it's reasonable that
improper pump belt tension is the cause.
Hard Steering
Dirt in the system has been found to be a cause of hard steering
as greater effort is required to reposition the spool and bring
the power steering into operation. The repair will be a complete
cleaning of the hydraulic system. A pump relief valve stuck in
the open position can be the cause of hard steering as there will
be zero pump pressure. This can easily be checked by using Tool
5176.
Fluid Level
- Check oil level in the reservoir by removing the reservoir
dip stick to determine oil level as indicated by fluid showing
on the dip stick (fig. 42).
- Fill to level with automatic transmission fluid "Type
A" bearing an "AQ-ATF" number. This is the same
oil as available for Powerglide transmissions and is available
through Chevrolet Dealer and Oil Company filling stations. Total
in system is 1 1/2 pts.
Bleeding Hydraulic System
After a pump or control valve has been installed or a disconnected
oil line is reconnected, the air that entered the hydraulic system
must be bled out, otherwise noisy and unsatisfactory operation
will result. The following procedure should be used to bleed the
hydraulic circuit:
- Fill oil reservoir to proper level and let oil remain undisturbed
for about two minutes.
- Raise front end of vehicle so that wheels are off the ground.
- Start the engine and run at idle for two minutes.
- Increase engine speed to approximately 1500 RPM.
- Turn the wheels (off ground) right and left, lightly contacting
the stops.
- Lower the car and turn the wheels right and left on the ground.
- Recheck for leaks.
- Check oil level and refill as required.
Pump Belt Tension
Adjustment
- Loosen the outer bracket to generator bolt and retaining bolt
on the generator rear brace (fig. 41).
- Pull the generator out from the engine with all slack taken
out of the belt.
- Tighten the retaining bolts.
- Push in on the belt midway between the water pump and generator
pulleys with light push.
- If tension is correct there will be 5/16 inches of deflection
on 6 cylinder and 13/16 inches on 8 cylinder with a light push
at this point.
Checking Pump Pressure
- Disconnect the pressure line at the pump connection (smallest,
top line). CAUTION: Some fluid will leak out when the line
is disconnected so provision must be made to collect this drainage.
- Install checking gauge Tool 5176 (with gauge valve closed)
on the pump and hose connection. NOTE: Adapter kit 5900 must
be used to adopt pressure gauge to pump.
- Open the gauge valve and run engine at idle.
- Turn wheels (on ground) against stops. Pressure should not
be less than 750 psi.
- If pressure is less than 750 psi, slowly close gauge valve
observing gauge for pressure increase. Pressure will increase
as valve is closed if pump is good. CAUTION: Do not leave
valve closed for more than 15 seconds.
- If pressure does not increase when the valve is closed, difficulty
is in the pump, which must be removed for service.
- Shut engine off, remove gauge and valve, reconnect hose to
pump if pressure is O.K.
- Bleed hydraulic system of air as outlined under "Bleeding
Hydraulic System."
Steering Wheel Alignment
Refer to Section 9. Steering Wheel Alignment.
Major Service Operations
Reservoir and Pump Assembly
Cleaning and Inspection
Assembly
Reservoir and Pump Assembly
Removal
Disassembly
Removal
NOTE: Omit steps 1 and 2 an 8 cylinder models.
- Loosen generator to bracket retaining bolts and remove fan
belt.
- Pull the generator all the way out from the engine.
- Place a container under the pump and disconnect the hydraulic
lines from the pump allowing the oil to drain out of the reservoir
into the container (fig. 43).
- Remove the retaining bolts from the pump to generator and
generator rear brace on 8 cylinder models and remove the pump
from the vehicle (fig. 44).
- Complete draining the remaining oil from the pump reservoir
before disassembly.
Disassembly
- Remove the two retaining bolts and sealing washers from pump
reservoir to pump cover assembly (fig. 45).
- Remove the reservoir from the pump assembly.
- Remove the oil filter spring retainer from the pump cover
assembly.
- Remove the spring retainer and plate from the pump cover assembly.
- Remove plug and "O" ring, flow spring and pressure
relief valve assembly from the pump cover assembly.
- Remove the three retaining bolts from the pump cover assembly.
- Remove the pump cover from the pump body assembly and remove
the oil filter and retainer.
- Remove the cam ring, pump rotor and vanes.
- Remove the pressure plate from the pump cover assembly.
- Remove and discard the "O" rings from the pump cover,
cam ring, and pump body.
- Remove and discard the generator shaft oil seal from the pump
body assembly.
Cleaning and Inspection
- Wash all parts in cleaning solvent and wipe dry with a lint
free cloth.
- Inspect the fit of vanes in rotor. Vanes must slide freely,
but snugly in slots. Tightness may be relieved by thorough cleaning
or removal of irregularities.
- Inspect flat faces of pressure plate, cam ring, pump cover,
rotor and pump body. These faces may be repaired by lapping until
smooth and flat, after which all lapping compound must be thoroughly
washed away.
- Inspect cylindrical surface of pressure relief control valve
and check fit of pressure relief control valve in pump cover.
Slight irregularities may be corrected by polishing.
Assembly
Assembly
Control Valve Removal and Disassembly
Control Valve Cleaning and Inspection
Control Valve Inspection and Assembly
Assembly
- Lubriplate and install new "O" rings in the pump
cover, on the cam ring, and in the pump body.
- Install the rotor and vanes on the pump body with wear pattern
or beveled edge of vanes against cam ring inner diameter.
- Install the alignment sleeve in the cam ring and install the
cam ring on the pump body. CAUTION: The wider edge of the
cam ring is the correct side to the pump body. Be certain to align
bolt holes in the cam ring to pump body bolt holes. The rotor
should be installed with the rounded side of the splines toward
the generator end of the pump.
- Install the pressure plate in the pump cover.
- Install the filter retainer and oil filter on the pump cover.
- Install the pump cover assembly and three retaining bolts
to the pump body.
- Install the plunger and flow spring in the pump cover assembly.
- Install the plug and "O" ring assembly, cover plate,
and retainer spring.
- Install the oil filter retainer spring in the pump cover.
- Install the reservoir, two retaining bolts, and two sealing
washers. NOTE: The brass fitting seats are of the pressed in
type and are replaceable in the event of a fitting leak by tapping
threads in the hole of the seat and then pulling the seat by using
a bolt threaded into the tapped out seat and a flat washer and
nut as an extractor.
- When installing new seats, align the seat in its bore and
press it into place using the correct hose or tube fitting as
a pressing tool.
- Install pump on vehicle and fill and bleed system as outlined
under "Care, Maintenance and Adjustments."
Control Valve Removal and Disassembly
Removal
- Raise the front of the vehicle off the floor and place it
on stands.
- Loosen the relay rod to control valve clamp (fig. 46).
- Disconnect the two pump to control valve hose connections
and allow fluid to drain into a container, then disconnect the
two remaining valve to power cylinder hoses.
- Remove the retaining nut from the ball stud to pitman arm
connection and disconnect the control valve from the pitman arm.
- Turn the pitman arm to the right clear of the control valve
and unscrew the control valve from the relay rod (fig. 47).
- Remove the control valve from the vehicle
Disassembly
- Remove dust shield (1) (fig. 48)
from the control valve housing (2).
- Remove retaining pin and nut (3) from the valve shaft.
- Remove the retaining bolts connecting the valve assembly housing
to the adapter assembly housing and separate the two assemblies.
NOTE: Valve spool remains in the housing when the two assemblies
are separated, because the seal at the end of the spool will not
allow spool removal other than from the end of the housing.
- Remove the spring thrust washer (7), spring (8), flat washer
(9), vee seal assembly small washer and spacer (15) from the valve
shaft.
- Remove the ball stud cover (13) (fig. 39)
from the adapter assembly housing (11).
- Push the ball stud (8) to the end of the adapter housing and
remove the lock pin (4).
- Remove the threaded ball plug adjuster (3) and valve shaft
(1).
- Remove the ball seat plug (5) and spring (6).
- Remove the ball seats and ball stud.
- Remove the bearing sleeve (10).
Inspection
- Wash all metal parts in solvent cleaner and dry them with
a lint free cloth.
- Inspect all parts for scratches, burrs distortion, evidence
of wear and replace a worn or damaged parts, including mating
parts where necessary.
- Replace all seals, gaskets, covers with approved service parts.
Assembly
- Replace the ball seat (9) (fig. 39)
in the bearsleeve (10) and insert the sleeve in the housing (11).
- Insert the ball stud (8) in the sleeve.
- Install the remaining ball seat (7), spring (6) and spring
seat (5) in the bearing sleeve. CAUTION: This is the heavier
of the two springs used in the control valve.
- Install the valve shaft (1) in the adjuster (3) and screw
the adjuster into the bearing sleeve. NOTE: The adjuster should
be tightened until it bottoms, and should then be backed off 1/4
turn plus or minus amount necessary to insert lock pin in nearest
hole. CAUTION: Be sure ball seats remain in correct
position, otherwise there will be insufficient clearance to correctly
install the retaining pin.
- Install the ball stud cover (13).
- Install the washer (2) fig. 39
and annulus spacer (15) fig. 48
on the valve shaft.
- Install the vee seal block (14) fig. 48
and ring assembly (10, 11, 12, 13) fig. 48.
- Install the annulus washer, spring and spring thrust washer
(7) fig. 48. CAUTION:
Chamfer side of the thrust washer to be toward spool side.
- Install the spool valve assembly and retaining nut. CAUTION:
The spool valve is installed with the vee seal at the threaded
end of the valve shaft.
- Tighten the retaining nut to 25 in. lbs. with a torque wrench
and install the retaining clip. CAUTION: Be sure all parts
including spring, are correctly located before tightening.
- Insert the assembled valve and adapter assembly into the valve
housing and install the two retaining bolts and lockwashers.
- Fill the end area with GM 4617-M grease and install the valve
housing dust cover.
Installation
- Install the control valve on the relay rod (fig. 49)
so that the distance from center of control valve ball stud to
the center of the tie rod end ball stud measures approximately
3 5/8".
- Tighten the control valve clamp. NOTE: The clamp securing
the control valve to the relay rod end should be positioned before
tightening so that it will not interfere with the steering linkage.
- Reconnect the four hydraulic hoses to the control valve.
- Fill the system with type "A" fluid and bleed out
air using the procedure outlined under "Care, Maintenance
and Adjustments."
Power Cylinder
Removal
Inspection and Seal Replacement
Installation
Removal
- Disconnect the two hydraulic lines (5) (fig. 50)
connected to the power cylinder and drain fluid into a container.
- Remove retaining nut, washer, and rubber grommet from power
cylinder rod to the brace attached to the frame.
- Remove the cotter pin, retaining nut, flat washer and bolt
from the end of the power cylinder where it is fastened to the
relay rod bracket.
- Remove the power cylinder from the vehicle.
Inspection and Seal Replacemnt
- Inspect the seals for leaks around the cylinder rod and if
leaks are present replace the seals, using the following procedure:
- Use a hook tool and remove the retaining ring (fig. 51).
- Remove the wiper ring.
- Remove the back up washer.
- Remove the back up ring seal.
- Remove the seal. NOTE: The piston rod seal should not be
removed unless there are signs of leakage along the piston shaft
at the shaft seal.
- Examine the brass fitted hose connection seats for cracks
or damage and replace if necessary.
- For service other than seat or seal replacement, replace the
power cylinder.
Installation
- Install the power cylinder on the vehicle by reversing the
removal procedure.
- Reconnect the two hydraulic lines, fill the system with fluid
and bleed out air using the procedure outlined under "Care,
Maintenance and Adjustments."
Trouble Diagnosis
This section will cover only those causes of trouble which may
be due to the hydraulic power steering mechanism. Before assuming
that the hydraulic power mechanism is at fault, make sure the
mechanical components are in good condition. The mechanical items
include: front wheel alignment, tire condition and pressure, wheel
bearing adjustment, lubrication and adjustment of steering linkage,
and proper alignment of steering gear in mounting to eliminate
bindings.
1. Hard Steering
To determine whether hard steering actually exists, place
car on a clean, dry floor, apply brakes, and with engine idling,
turn wheel to the extreme right and left and hold against the
stop momentarily in each direction several times. This will bring
the oil temperature to approximately 170F which is operating temperature.
Apply Tool 5178 (15 lbs.) to a spoke at rim of steering wheel
and check the pull required to turn the wheel steadily with gauge
held at 90 degrees to the spoke. If the pull required to turn
the wheel exceeds 10 pounds, check the following causes.
Possible Causes
a. Generator drive belt loose.
b. Low oil level in reservoir.
c. Air in hydraulic system.
d. Insufficient oil pressure.
e. Steering adjustment tight.
2. Excessive Play or Looseness in Steering Mechanism
a. Loose worm thrust bearing adjustment.
3. Low Oil Pressure
If it is believed oil pressure is low, the pressure should be
checked as outlined in "Care, Maintenance and Adjustments"
using Tool J-5176.
a. Generator drive belt loose.
b. Low oil level in reservoir.
c. Pump mechanical difficulty-possibly caused by:
(1) Relief valve; improper adjustment, weak relief valve
spring or relief valve stuck open.
(2) Control valve stuck or broken flow control spring.
(3) Worn rotor parts.
d. Pressure loss in steering control valve, possibly caused
by sticking valve spool or discharge
valve stuck open.
e. Pressure loss in power cylinder, possibly caused by leaking
seal.
f. External or internal oil leaks.
4. Poor Centering or Recovery on Turns
a. Valve spool sticking in valve housing.
b. Binding of steering shaft.
c. Loose worm thrust bearing adjustment.
d. Sticky cylinder assembly.
5. Oil Pump Noisy
a. Improper oil level.
b. Air in system.
c. Reservoir air vent plugged.
d. Sludge or dirt in pump.
e. Pump bearings, shaft, vanes or other rotating parts worn
or damaged. Sticking pump
vanes also a possibility.
6. Oil Leaks
a. Loose connections at hose unions or
oil pipe elbows.
b. Loose connection or faulty "O" rings in pump.
c. Hose leaks.
External-Possible Causes
a. Leaking housing.
b. Cylinder seal leaking.
Assembly Manual
Steering Mechanism
Steering Linkage
Steering Gear
Steering Wheel
Instrument Panel Brace Assembly
Dash Brace and Steering Gear Jacket Braces
Steering Column and Clutch Rod Dash Seal
Hydraulic Steering
Hydraulic Steering Bleeding
Linkage