Chevrolet 70 1969 Series, Shop Manual

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E N G IN E 6-28
1. Remove housing from cylinder block and look for dirt
or burrs on mating surfaces which may prevent hous­
ing from seating against cylinder block. Remove dirt
or burrs, reinstall housing and recheck for misalign­
ment.
2. If misalignment is due to distortion, or combination
of tolerances, try installing another housing from ser­
vice stock.
3. When a selection of housings is not available, housing
bore m ay be aligned by removing dowel pins (fig. 18)
from cylinder block, then align housing by shifting
housing while held loosely in place by mounting bolts.
If necessary, enlarge the mounting bolt holes to per­
mit additional movement.
4. When aligned, tighten housing bolts firmly, then ream
dowel pin holes to a convenient oversize and install
oversize dowel pins.
Figure 4 5 — Typical Use o f S p r e a d e r Tool for In sta llin g Piston R in g s
NOTE: On engines used with automatic trans­
mission, instructions for installing flywheel are
included previously in connection with housing
installation.
1. Locate flywheel at crankshaft flange with mounting
holes aligned. C ne hole is offset, and flywheel can be
installed in only one position.
2. Install flywheel on crankshaft flange using lock plate
under each pair of self-locking bolts. A lock plate
with a small hole for identification is used on odd
spaced bolts. Refer to Figure 44. Six bolts are used
on 401 M and eight bolts on 478 M engines.
3. Tighten flywheel bolts to 100 to 110 foot-pounds.
4. M oun t dial indicator and check flywheel run-out at
machined surface. Refer to “ Specifications” at end of
this section for run-out specifications at fly wheels.
PISTON AND CONNECTING
ROD INSTALLATION
The piston rings for engines covered in this section dif­
fer as illustrated in Figures 46 and 47, and procedures for
installing piston rings of various types are given separate­
ly. l i e ‘ preader tool typically illustrated in Figure 45 fa­
cilitates ring installation.
1. 4 01 M Engines (Fig. 47).
a. Referring to Figure 67, install all compression
rings (2, 3, and 5) in respective grooves with the
inside bevel toward top of piston as shown in
inset. These two compression rings are the same.
b. Install oil control ring (7) in botto m groove.
Oil control ring m ay be installed with either side
upward.
2. 478 M Engines (Fig. 48)
a. Referring to Figure 48, place oil ring expander
FLYWHEEL INSTALLATION
1 Piston
2 Top Compression Ring
(Moly-filled)
3 2nd Compression Ring
(Inside Bevel)
4 3rd Compression Ring (Inside
Bevel, Reverse Twist)
5 3rd Compression Ring (Inside
Bevel)
6 Cylinder Wall
7 Oil Control Ring (One-Piece
Flexible)
8 Top Groove Insert (Integral
with Piston)
T-2692
Figure 4 6 — Piston Ring Arrangem ent for 4 0 1 M Engines
CHEVROLET SERIES 70-80 H EAVY DUTY TRUCK SH O P M A N U A L