Chevrolet Light Duty Truck 1973, Service Manual

Page: 838 / 979

9 -7 2 STEERING
DIAGNOSIS C AND K
This section contains diagnostic information to help
locate the cause of the problem in the column. Reference
should be made to the correct method of column
disassembly, repair, adjustment and reassembly. Dam­
aged, broken or deformed parts must be replaced with
the correct replacement.
GENERAL INFORMATION
All C and K models are equipped with function locking
energy absorbing Steering Columns. The columns are of
five basic designs as follows:
1.
Synchromesh
— The synchromesh column is used
on models with the standard transmission and
column mounted shift levers. The shift tube, within
the outer column jacket, includes two lower shift
levers for connection to the transmission control
linkage.
2.
Floor Shift
— This column is used on models
equipped with a manual transmission with the shift
lever on the floor. This column does not incorporate
a shift tube.
3.
AUTOMATIC TRANSM ISSIO N-
Available with col­
umn shift only Locks the transmission and steering
wheel while in park position and the lock cylinder is
in "Lock" position.
4.
TILT WHEEL OPTION
- The upper end and
steering shaft of this column is specifically designed
to accommodate the optional tilt steering wheel. It
is available with either manual (the fourth column
type) or automatic transmission on (the fifth
column type).
To perform diagnostic procedures on the steering
column upper end components, it is not necessary to
remove the column from the vehicle.
The steering wheel, horn components, directional signal
switch, ignition switch and lock cylinder may be removed
with the column remaining in the vehicle as described in
the Service Manual under “Component Part
Replacement”.
CAUTION:
The outer mast jacket shift tube,
steering shaft and instrument panel mounting
bracket are designed as energy absorbing units.
Because of the design of these components, it is
absolutely necessary to handle the column with
care when performing any service operation.
Avoid hammering, jarring, dropping or leaning
on any portion of the column. When reassem­
bling the column components, use only the
specified screws, nuts and bolts and tighten to
specified torque. Care should be exercised not
to use over-length screws or bolts as they may
prevent a portion of the column from
compressing under impact.
STEERING COLUMNS
COLLISION DIAGNOSIS
To determine if the energy absorbing steering column
components are functioning as designed, or if repairs are
required, a close inspection should be made. An
inspection is called for in all cases where damage is
evident or whenever the vehicle is being repaired due to
a front end collision. Whenever a force has been exerted
on the steering wheel or steering column, or its
components, inspection should also be made. If damage
is evident, the affected parts must be replaced.
The inspection procedure for the various steering column
components on C and K trucks is as follows:
COLUMN SUPPORT BRACKET
Damage in this area will be indicated by separation of
the mounting capsules from the bracket. The bracket will
have moved forward toward the engine compartment
and will usually result in collapsing of the jacket section
of the steering column.
COLUMN JACKET
Inspect jacket section of column for looseness, and/or
bends.
SHIFTER SHAFT
Separation of the shifter shaft sections will be internal
and cannot be visually identified. Hold lower end of the
“shifter shaft” and move “shift lever” on column
through its ranges and up and down. If there is little or
no movement of the “shifter shaft”, the plastic joints are
sheared.
Steering Shaft
If the steering shaft plastic pins have been sheared, the
shaft will rattle when struck lightly from the side and
some lash may be felt when rotating the steering wheel
while holding the rag joint. It should be noted that if the
steering shaft pins are sheared due to minor collision
with no appreciable damage to other components, that
the vehicle can be safely steered; however, steering shaft
replacement is recommended.
Because of the differences in the steering column types,
be sure to refer to the set of instructions below which
apply to the column being serviced.
Method To Determine Column Collapse
Measure distance between top of neutral-start switch
window opening and the bottom of the upper jacket. The
correct value is shown below:
a. C-Truck 5 11/16" to 5 1/2".
b. K-Truck 5 11/16" to 5 1/2".
LIGHT DUTY TRUCK SERVICE MANUAL