Chevrolet 10 Series 1968, Service Manual

Page: 600 / 713

ELECTRICAL—BODY AND CHASSIS 12-15
F ig . 20- Instrument Cluster Removal - T ilt Cab
2. Pull bulb straight out to remove from holder.
3. Install replacement bulb in holder, press inward to
lock in place.
4. Insert holder into housing, with lugs on holder enter­
ing notches in case, and turn clockwise to lock in
place.
A ll Other Models
To replace any indicator or illuminating bulb, unsnap
the proper socket from rear of instrument cluster, re­
place bulb, and reinsert unit onto rear of cluster housing.
LAMINATED CIRCUIT REPLACEMENT
10-60 Conventional Cab Models
1. Remove instrument cluster assembly as previously
described in this section.
2. Remove all instrument cluster lamp assemblies.
3. Remove laminated circuit retaining screws.
NOTE:
These screws serve as a ground for
the circuit and must be reinstalled to provide
the proper ground connections for the laminated
circuit.
4. Remove fuel, temperature and ammeter terminal
nuts retaining laminated circuit to cluster cover.
5. Remove laminated circuit from rear of instrument
cluster.
6 . To install, reverse removal procedure and check
operation of unit.
SPEEDOMETER REPLACEMENT
NOTE: Servicing of the speedometer assembly
should be performed by an authorized AC Speed­
ometer Service Station.
Conventional Cab Models
1. Remove instrument cluster assembly and laminated
circuit as previously described in this section.
2. Remove retaining screws and cluster rear cover.
3. Remove front cover from face of cluster.
4. Remove two retaining screws and speedometer from
cluster.
5. To install, reverse removal procedure and check op­
eration of unit. DO NOT KINK CABLE HOUSING.
Flatface Cowl Models
1. Disconnect battery ground cable.
2. Disconnect speedometer cable and all indicator and
illuminating sockets.
3. Remove three screws attaching speedometer housing
to dash panel.
4. Pull speedometer from opening in dash panel.
5. To install, reverse removal procedure and check
operation of unit. DO NOT KINK CABLE HOUSING.
Chevy Van, P Models
1. Remove instrument cluster assembly as previously
described in this section.
2. Remove four screws securing cluster back panel to
bezel assembly.
NOTE: Assemble the two parts with alignment
dowels properly positioned.
3. Remove two screws securing speedometer head to
cluster back panel; carefully remove speedometer
head.
4. To install, reverse removal procedure and check
operation of unit. DO NOT KINK CABLE HOUSING.
Tilt Cab Models
1. Remove instrument cluster assembly as previously
described in this section.
2. Remove eight screws securing cluster bezel to back
panel assembly and remove bezel.
3. Remove two screws attaching speedometer head to
back panel assembly and carefully remove speedom­
eter head.
4. To install, reverse removal procedure and check
operation of unit. DO NOT KINK CABLE HOUSING.
SPEEDOMETER CABLE REPLACEMENT OR
LUBRICATION; ALL MODELS
1. Disconnect speedometer cable from the overspeed
switch on Tilt Cab Models, speedometer head on
other models.
2. Remove old cable by pulling it out from speedometer
end of conduit.
NOTE: If old cable is broken it will be nec­
essary to remove lower piece from transmission
end of conduit.
3. Lubricate the lower 3/4 length of cable with speed­
ometer cable lubricant and feed the cable into the
conduit. DO NOT KINK SPEEDO CABLE HOUSING.
4. Connect the upper end of cable to the speedometer
head, or overspeed switch, and road test the truck
for proper speedometer-odometer operation.
CHEVROLET TRUCK SERVICE MANUAL