Chevrolet 70 1969 Series, Руководство по ремонту

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E N G IN E 6-29
Assemble With
Bevel Side
Toward Top
of Piston
Assemble With
Scraper Edge
Toward Bottom
of Piston
1 Piston
2 Ring Insert
(Integral with
Piston)
3 Top Compression
Ring (Chrome
Faced)
4 2nd Compression
Ring
7 5 3rd Compression
Ring (Inside Bevel
Reverse Twist)
6 Oil Ring Expander
Install Oil Ring With Expander 7
Qil Control Ring
Toward Top of Piston As Shown TPM 9|39
Assemble With
Bevel Side
Toward Bottom
of Piston
Figure 4 9 — E n g in e C r a n k c a se w ith C o n n e c tin g Rods a n d O il P u m p In ­
stalled ( 4 0 1 M E n g in e S h o w n )
Figure 4 7 — Piston R in g A r r a n g e m e n t on 4 7 8 M E n g in e
1. Oil Inlet Screen and
Pipe Assy.
2. Rod Identification
Numbers (2, 4 and 6)
3. Rod Identification
Numbers (1, 3 and 5)
4. 45 degrees Elbow
5. Governor line
6. Gasket
7. Governor Spinner
Valve Assy.
in piston bottom groove and insert expander lock­
ing wire into spring coil to hold ends of expander
spring in alignment. Use ring spreader (fig. 46) to
spread oil ring and install oil ring with expander
groove toward top of piston.
NOTE: Be sure the teflon sleeve is in place on
oil ring expander spring so ring gap will be at
center of sleeve when ring is installed.
b. Install 3rd compression ring (5) with bevel side
and bottom of piston.
c. Install 2nd compression ring (4) with scraper
edge toward bottom of piston.
d. Install top compression ring (3) with the inside
bevel toward top of piston.
3. Installing Piston and Connecting Rod Assembly
a. Apply engine oil on piston pin and piston rings.
Wipe cylinder bores with clean cloth and thor­
oughly coat cylinder bores with engine oil.
b. Stagger gaps in piston rings so that no two caps
are closer than 30 degrees to each other. On
401M engines, ends of oil ring must be located
over a so ,d portion of the piston — N O T over
a slot.
NOTE: If rings are used which are designed for
oil control in cylinders not reconditioned, follow
instructions furnished by piston ring manufactu­
rer.
c. Place connecting rod bearing halves in rod and
cap. Lubricate the crankshaft journals with engine
oil, and assembly guide set (fig. 19) on connect­
ing rod bolts.
d. Use a sleeve type piston ring compressor of type
illustrated in Figure 49 to install pistons and
rings in cylinder bores.
Use necessary care to match numbers stamped on con­
necting rods and caps (fig. 49) with cylinder num bers (fig.
21). Odd numbers 1, 3, etc., are at left side of block and
even numbers 2, 4, etc., are at right side.
Position the piston ring compressor over the piston
rings, pushing the piston through far enough to assure
correct seating of oil ring in groove. Start piston into cyl­
inder bore and seat the ring compressor squarely at cylin­
der block. W hen installing pistons in 4 0 1 M engines, be
certain the ends of oil ring are butted together not ov­
erlapped; then with ham m er handle force the piston and
rings into cylinder bore with a Q U IC K , F I R M , P U S H .
CHEVROLET SERIES 70-80 HEAVY DUTY TRUCK SH O P M A N U A L