Buick LeSabre 1965 Service Manual page 51

ENGINE
HEADS AND VALVES 2 - 2 9
SECTION 2-D
CYLINDER HEAD AND VALVE MECHANISM SERVICE
Paragraph
2-13
2-14
Subject
CONTENTS OF SECTION 2-D
Page Paragraph Subject
Cylinder Head and Valve Service. . 2-29
Hydraulic Valve Lifter Service . . . 2-32
2-15 Timing Chain, Cover and
Camshaft Service . . .
2-35
2 - 1 3 CYLINDER HEAD
AND VALVE SERVICE
a. Removal of Cylinder Head
1. Drain the radiator and cylinder
block.
2. Remove a i r c l e a n e r and
silencer, then disconnect all pipes
and hoses from carburetor and
intake manifold.
3. Disconnect wires from accel-
erator vacuum switch, remove
coil, remove t h r o t t l e return
spring.
4. Remove intake manifold and
carburetor as an assembly. Re-
move manifold gaskets.
5. When removing RIGHT cylin-
der head; (1) remove oil gauge
rod, (2) d i s c o n n e c t automatic
transmission filler pipe bracket
from head, (3) remove generator
mounting bracket, (4) remove air
c o n d i t i o n i n g compressor, if
present.
6. When removing LEFT cylinder
head; (1) remove power steering
gear pump with mounting bracket
if present, and move it out of the
way with hoses attached.
7. Disconnect wires from spark
plugs.
8. Disconnect w a t e r manifold
from both cylinder heads and dis-
connect exhaust manifold from
head to be removed.
9. With air hose and cloths, clean
dirt off cylinder head and adjacent
area to avoid getting dirt into
engine. It is extremely important
to avoid getting dirt into the hy-
draulic valve lifters.
10. Remove rocker arm cover
and remove rocker arm and shaft
assembly from cylinder head. Lift
out push rods.
NOTE: Due to the close clear-
ances in the engine compartment
it is necessary to leave some of
the bolts and push rods in the
head during removal. The push
rods should be pulled up and taped
in position while cylinder head is
being removed. These same parts
must be in the head d u r i n g
installation.
11. Slightly loosen all cylinder
head bolts then remove bolts and
lift off the cylinder head. Remove
gasket.
12. With cylinder head on bench,
remove all spark plugs for clean-
ing and to avoid damage during
work on the head.
b. Reconditioning Valves
and Guides
1. Place cylinder head on Holding
Fixture J-5251 with valve springs
s t r a i g h t up. Compress valve
springs with fixture lever and
remove the spring cap keys, then
remove the springs and caps. See
Figure 2-20.
2. Carefully roll cylinder head
away from holding fixture until
one edge rests on bench, then
remove valves. Place valves in
a stick with numbered holes to
keep them in order for reinstal-
lation in original positions.
3. Scrape all carbon from com-
bustion chambers, piston heads,
and valves. Clean all carbon and
gum deposits from valve guide
bores. When using scrapers or
wire brushes for removing car-
bon, avoid scratching valve seats
and valve faces.
4. Inspect valve faces and seats
for pits, burned spots or other
evidences of poor seating. If a
valve head must be ground until
the outer edge is sharp in order
to true up the face, discard the
valve because the sharp edge will
run too hot.
5. Check fit of valve stems in
guides. If clearance is excessive
replace the guides on 401 and
425
;
s, as follows:
(a) Remove center crossbar from
Holding Fixture J-5251, p l a c e
cylinder head in fixture so that
inlet port side rests against the
fixture lower bar, t h e n drive
Figure 2-21—Removing Valve in
Holding Fixture J-5251