Chevrolet 10 Series 1970, Руководство по обслуживанию

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ENGINE 6-28
F ig . I V — In ta ke M a n ifo ld G a s ke t and Seal L o c a tio n
Exhaust M a n ifo ld
Removal
NOTE: On ve h ic le s equipped with A ir Injection
R eactor System, disconnect a ir m anifold as
outlined in Section 6T. R em ove a ir p reh eater
stove.
1. On ve h ic le s so equipped, rem ove ca rb u retor heater.
2. On le ft exhaust m anifold, disconnect and rem ove
D elcotron.
3. On " M a r k IV V 8” engines, rem ove spark plugs.
4. Disconnect exhaust pipe from m anifold and hang
exhaust pipe from fra m e with w ire.
5. R em ove end bolts then rem ove center bolts and
rem ove m anifold.
Installation
1. Clean mating su rfaces on m anifold and head, then
install m anifold in p o s i t i o n and in stall bolts
(fin g e r-tig h t).
2. Torqu e m anifold bolts to specification s.
3. Connect exhaust pipe to m anifold. Use new gasket o r
packing.
4. On "M a r k IV V8” engines, install spark plugs.
Torqu e plugs to sp ecification s.
5. On le ft exhaust m anifold, install and connect D e lc o ­
tron. Adjust b elt as outlined in Engine Tune Up.
6. On v e h ic le s so equipped, install ca rb u retor heater.
7. Start engine and check fo r leaks.
Rocker Arm Cover
Removal
1. R em ove a ir clean er.
2. D isconnect A ir Injection R ea ctor hose at check valve.
3. Disconnect crankcase ven tilation hoses at ro ck er
arm c o v e rs .
4. Disconnect tem perature w ire fro m le ft ro ck er arm
clips.
5. On ve h ic le s so equipped, rem ove carb u retor heater
fro m le ft exhaust manifold*
6. R em ove ro ck er arm c o ver.
CA U TIO N : Do Not p ry ro ck er arm co v e r loose.
Gaskets adhering to cylin d er head and ro ck er
arm co v e r may be sheared by bumping end o f
ro c k e r arm c o v e r rea rw a rd with palm o f hand
or a rubber m allet.
Installation
1. Clean gasket su rfaces on cylin d er head and ro ck er
arm co v e r with d e g re a s e r then, using a new
gasket, install ro c k e r arm co v e r and torque to
sp ecification s.
2. Install ca rb u retor heater (if rem oved ).
3. Connect tem perature w ire at clip s on le ft rock er
arm c o ver.
4. Connect crankcase ventilation hoses (as requ ired ).
5. Connect A ir Injection re a c to r hose.
60 Install a ir clean er, start engine and check fo r leaks.
V a lv e Mechanism
Removal
1. R em ove rock er arm c o vers as outlined.
2. R em ove ro ck er arm nuts, ro c k e r arm b alls, rock er
a rm s and push rods.
NOTE: P la ce ro ck er arm s, ro c k e r arm b a lls
and push rods in a rack so they may be r e ­
in stalled in the sam e locations.
Installation and Adjustment
NOTE: W henever new ro ck er a rm s and/or
ro ck er arm b alls a re being in stalled, coat b e a r­
ing su rfaces o f rock er a rm s and ro c k e r arm
ba lls with "M o ly k o te ” o r its equivalent.
1. Install push rods. Be sure push rods seat in lifte r
socket.
2. Install ro ck er arm s, ro ck er arm b a lls and rock er
arm nuts. Tighten ro ck er arm nuts until a ll lash is
elim inated.
3. Adjust va lv e s when lifte r is on base c ir c le o f cam ­
shaft lobe as follow s:
a. Crank engine until m ark on torsion al damper
lin es up with center o r " O ” m ark on the tim ing
tab fastened to the crankcase front c o v e r and the
engine is in the number 1 firin g position. T h is
may be determ ined by placing fin g e rs on the
number 1 va lve as the m ark on the dam per com es
near the “ O ” m ark on the crankcase fron t co ver.
If the v a lv e s a re not m oving, the engine is in the
number 1 firin g position. If the v a lv e s m ove as
the m ark com es up to the tim ing tab, the engine
is in number 6 firin g position and should be
turned o v e r one m ore tim e to reach the number
1 position.
b. W ith the engine in the number 1 firin g position
as determ ined above, the follow in g va lv e s may be
adjusted.
Exhaust - 1, 3, 4, 8
Intake - 1, 2, 5, 7
CHEVROLET TRUCK SERVICE MANUAL