Chevrolet Corvette 1953 Operation Manual page 44

Always make adjUBtment by bending the side drx-
lJOde. Install tbe spark plugs in the engine blowing
away clift from around plug
holes and UBing new gaskets
whenever nrxessary and tightening to 20-25 fool pounds
lemion.
IT
torque
wrench
is not
available, tighten
finger
light and
~
turn more using new gaskets. Plugs are of
l ... millimetcr size and care must
be
exercised when in-
atalling or the setting of the gap may be upset.
VALVE ADJUSTMENT
Before adjusting the valve stem to rocker arm clearance,
it is extremdy important that tbe engine be thoroughly
armed up to normalize the expansion of all part •. This is
very important because the
v~ve
clearances
will
change
considerably during tbe warm-up period. Adjusting the
valves during or before this warm-up period will produce
dearances which will be
far from correct after the engine
reaches normal operating temperature.
Test! have shown tbat valve clearances will vary as much
... 005' from a cold check through the normalizing range.
To normalize all parts properly, the engine should be run
approximatdy 30 minutes.
Covering the radiator wiU
nOl
materially hastcn this nor-
malizing process because even with the water temperature
quickly raised
10
185
0
,
the rate at which the oil tempera-
ture increases or the engine pans beco'!lc normalized does
not change appreciably.
The actual temperature of the oil is not as important a
stabilizing the oil temperature. The expansion or contrae
tion of the valves, rocker arm supports, push rods, cylinde
head and cylinder block are relative to this oil temperatun
Therefore, only after the oil temperature is stabilized d,
these pa.ru stop expanding and vaJve clearances cease tl
change.
15 9
5 1
6 11
17
Fig. 64-G.l'lntln Head
Bolt 1Jt lttening
Diagram
1.
Remove the upper ignition shield.
2. Remove rocker arm cover
~uaching
bolts and cover.
3. Tighten all manifold bolts (4 cenler clamp bolts 15·20
ft. Ibs. torque; 2 end clamp bolts 25-30 ft . Ibs. torque),
valve rocker shaft suppOrt nuts and bolts (25-30 ft. Ibs.
torque) and cylinder head bolts (90-95 ft . l!>s. torque)
i.n sequence shown in Figure 64.
41