Chevrolet 10 Series 1968, Service Manual

Page: 482 / 713

CLUTCHES AND TRANSMISSIONS 7-19
the ends of the air lines to prevent entry of dirt
or other foreign material.
2. Remove the gearshift lever knob.
3. Loosen the control valve mounting clamp and re ­
move the control valve and mounting clamp from the
gear shift lever. Remove the mounting clamp from
the control valve.
Disassem bly (Refer to Fig. 8C)
1. Place control valve with rear housing (outlet side)
on the work bench and remove housing attaching
parts. Carefully separate the front and rear housings.
2. Remove the slide and the two position balls and
springs.
3. Remove the valve plate and “ O” ring from the rear
housing.
4. Remove valve insert from front housing and remove
the “ O” ring from valve insert.
5. Remove the wave washer installed under the valve
insert.
6 . Remove two felt seals from valve housings.
7. Remove roll pin from control button which releases
the slide from control button.
NOTE: The above step should be performed
only if the slide shows conditions of wear or
scoring, which requires replacement of the slide.
Cleaning and Inspection
1. Clean all metal parts thoroughly, using a suitable
cleaning fluid. Blow dry with air or wipe dry with
a clean lint-free cloth.
2. Check all parts for wear, distortion, cracks, or
other damage.
3. Replace all parts that would affect proper operation
of the control valve.
IM PORTANT: Be sure to use new “ O” rings
which are available in a service kit, when re ­
assembling the valve. Also, the “ O” rings and
the surfaces that operate against them are to be
lubricated, SPARINGLY, with silicone fluid lu­
bricant prior to assembly.
Assem bly (Refer to Fig. 8C)
1. Place the
“ O ”
ring, valve plate, felt seal, position
spring, and position ball in the rear housing.
2. Install
“ O ”
ring on the valve insert.
3. Place the wave washer, valve insert, felt seal, posi­
tion spring, and position ball in the front housing.
4. Position the slide in the control button and install
roll pin (if removed).
5. Position the control button and slide assembly on
the rear housing.
NOTE:
It is most important that the slot at
the lower end of the slide faces the OUTLET on
the rear housing.
6 . Carefully bring the front and rear housings together
and install housing attaching parts. Tighten nuts,
firmly.
Installation (Refer to Fig. 12C)
1. Place control valve and mounting clamp on gearshift
lever.
2. Install the gearshift lever knob.
3. Position the control valve and mounting clamp so that
the control button is at least 6 inches below the gear­
shift lever knob. Tighten clamp securely.
4. Remove protective caps from nylon air lines. Con­
nect the black air line to the outlet port of the con­
trol valve and connect the white air line to the inlet
port.
5. Pressurize air system and check for leaks (correct
as necessary).
6 . Road test vehicle and check for proper range shifts.
Air
Valve
Rem oval (Refer to Fig. 12C)
1. Disconnect all air lines from the air valve.
NOTE:
Be sure to place protective caps over
the ends of the air lines to prevent entry of dirt
or other foreign material.
2. Remove cap screws retaining air valve and gasket
to adapter plate.
NOTE: A ir valve is mounted on a special adap­
ter plate which is attached to transmission case.
3. Remove alignment sleeve shown in Figure 9C.
4. Remove actuating pin and spring from bore in adap­
ter plate.
5. Remove attaching parts retaining adapter plate and
gasket to transmission (if necessary).
6
. If necessary, remove fittings from air valve.
Disassem bly
Key numbers in text refer to Figure 9C.
1. Remove attaching parts retaining side cap to valve
housing.
2. Remove valve insert from piston and remove “ O”
ring (
2
) from the valve insert.
3. Remove the spring from piston.
4. Remove end cap from housing and withdraw piston
from housing bore.
5. Remove “ O” rings (1) and (4) from piston.
6
. Remove nylon plug from piston and remove “ O”
ring (3) from plug.
Cleaning and Inspection
1. Clean all metal parts thoroughly, using a suitable
cleaning fluid. Blow dry with air or wipe dry with a
clean lint-free cloth.
2. Check all parts for wear, cracks, distortion, or
other damage.
3. Replace all parts that would affect proper operation
of the control valve.
IM PORTANT: Be sure to use new “ O” rings
which are available in a service kit, when reas­
sembling the valve. Also the “ O” rings and the
surfaces that operate against them are to be
lubricated sparingly with silicone fluid lubri­
cant prior to assembly.
Assem bly (Refer to Fig. 9C)
1. Install new “ O” rings on valve insert, piston, and
plug.
2. Position plug in piston and insert piston in housing
bore. Install end cap on housing. Tighten end cap,
securely.
3. Position spring and valve insert in the piston. Install
the side cap on housing. Tighten attaching parts
securely.
CHEVROLET TRUCK SERVICE MANUAL