Chevrolet 70 1969 Series, Shop Manual

Page: 663 / 913

POWER BRAKE 5-54
crankcase. Tighten cap screws firmly.
6. Insert crankshaft and front ball bearing, as an assem ­
bly, through crankcase bearing bore and press front
ball bearing into crankcase front bore by using an
arbor press. M ake sure that a suitable tool is used to
press bearing and crankshaft assembly into crankcase.
The tool, which can be im provided locally (using a
section of tubing), m ust press on the outer race of
bearing to insure no shifting of ball bearings or d a m ­
age to the bearing assembly. Refer to Figure 16 for
tool dimensions.
IMPORTANT
Before pressing the bearing and crankshaft
assembly into crankcase, make sure that the
crankcase is properly supported. This will pre­
vent damage to rear cover pipe plugs or cap
screws.
7. Install new oil seal in front bearing cap. Place a new
gasket ori bearing cap and slide bearing cap on cran k­
shaft.
8. Install cap screws and lock washers attaching end
cover to crankcase. Tighten cap screws firmly.
GEAR-DRIVEN TYPE
1. Place front thrust washer on crankshaft with oil
grooves tow ard shoulder on shaft.
2. Insert crankshaft through end cover opening in
crankcase.
3. Position rear thrust washer on crankshaft with oil
grooves toward shoulder on shaft.
4. Install rear end cover oil seal in groove of rear end
cover.
5. Position rear end cover and bearing assem bly on
crankshaft until end cover is against the crankcase.
6. Install cap screws and washers attaching rear end
cover to crankcase. Tighten cap screws.
7. Install key in keyway in front end of crankshaft, in­
stall drive hub on shaft, and secure with nut and cot­
ter pin.
NOTE: Crankshaft should rotate freely.
Place new cylinder block gasket on crankcase. Position
cylinder block on crankcase, aligning m arks m ade before
disassembly. Install cap screws and washers. Tighten
firmly.
PISTON A N D C O N N E C T IN G ROD
ASSEMBLY A N D INSTALLATION
1. Position connecting rod in piston and press piston pin
into piston with lock wire holes in pin aligned with
Figure 16— Pressing Main Bearing Using Arbor Press Tool
lock wire holes in piston (refer to fig. 17). The piston
pin can be rotated by inserting a screwdriver into the
piston pin slot (fig. 18) to align piston pin lock wire
hole with the lock wire hole in the piston boss.
2. Install new piston pin lock wires in piston pin so that
long end extends through piston and pin. Snap short
end into lock wire hole at bottom of piston skirt.
3. Install piston rings in grooves of pistons. Rings m ust
be installed in proper location and with pip m arks
(m ay be num bered I to 5) upw ard. Refer to Figures
12 and 13 for proper clearance dim ensions and loca­
tion of rings on pistons.
4. Press bearing inserts into rod and cap by hand, with
locating lips in proper alignment.
NOTE: All locating lips are on the same side as
cap bolt (fig. 19).
5. Lubricate pistons, rings, piston pin bushings, and
bearing inserts with clean engine oil.
6. T urn crankshaft to position bearing journal nearest
drive end of crankshaft (No. 1) dow nw ard. Remove
bearing cap from No. 1 connecting rod.
NOTE: Stagger ring gaps 120 degrees from
each other before inserting pistons into cylinder
block. Refer to Figure 19 for an example of
staggered ring gaps.
CHEVROLET SERIES 70-80 HEAVY DUTY TRUCK SH O P M A N U A L