Ford F100 1959 Shop Manual page 16

1·12
TABLE
3-Va lve
Engine
SO
v-s
If
the valve face runcut is exces-
sive and/or to remove pits and
grooves, grind the valve 1 0 a true 45
0
angle. Remove only enough stock to
correct the runcut or to clean up the
pits and grooves. If the edge of the
valve head is less than
Y.n
inch after
refacing, replace the valve as the
valve
will
run too hot in the engine.
Grind off all grooves or score
marks from the end of the valve stem,
then chamfer as necessary.
Do
not
remove more than 0.010 inch from
the stem.
Afte r refacing the valves,
it
is good
practice to Ijghtly lap in the valves
with a medium grade lapping com-
pound to match the seats. Be sure 1 0
remove all of the compound from the
valve and seat aflCr the lapping op-
eral ion.
SlUCT "nING VALVIS
If the va lve stem
to
the va lve guide
clearance exceeds the wear limit, it is
recommended that the valve guide be
reamed for the next oversized valve
stem. Valves with oversize stem diam-
GROUP 1- ENGINES
eters of 0.003, 0.015, and 0.030 inch
are available fo r service. Always re-
face the valve seat when the valve
guide
is
reamed.
VALVI TIMING
The valve tim in g s hould be
checked when poor engine perform-
ance is noted and all other checks,
such as carburetioD, ignition liming,
etc. fail to locate the cause of the
trouble.
Before the valve timing is checked,
check for a bent timi ng pointer.
Bring the No. I piston to T.O.C. on
the compression stroke and see if the
timing pointer is aligned with the
T.O.C. mark on tbe damper.
If the valve liming is not within
specifications, check Ihe liming chain,
ca mshaft sprocket or gear, crank-
shaft sprocket or gear, camshaft, and
crankshaft in the order of accessi-
bility.
To check the valve timing with the
engine installed in the truck, proceed
as fo llows:
Install a quadrant on the crank-
shaft damper. Back off the No. I
intake valve adjusting screw, then
sl ide the rocker arm 1 0 o ne side and
secure it in this position. Make sure
the push rod is in the tappet socket,
then install a dial indicator in such. a
manner as to have the actuating point
of the indicator in the push
rod
socket
and in thc same plane as the push.
rod movement (Fig. 18). Turn the
crankshaft damper slowly in the di-
rection of rotation until the tappet
is on the base circle of the camshaft
lobe. At this point the push rod will
be in its lowest position. Zero the dial
indicator and continue turning the
crankshaft slowly in the direction of
rotation until the dial indicator reg-
isters the specified camshaft lobe lift
(Table )).
Compare the crankshaft degrees
indicated on the quadrant with speci-
fications (Table ). After the valve
opening is checked, continue to ro-
tate the engine to check the valve
closing.
D
TIMING CHAIN, TIMING GEARS, CAMSHAFT, AND BEARINGS
TIMING CHAIN-223 SIX,
292 MD AND HD
v-a
CUANIN G AND INSPECTION
Clean all parts in solvent and dr y
them with. compressed air. Inspect the
c h ain for broken li nks and the
sprockets for cracks, worn or dam-
aged teeth. It is recommended th.at all
the components be replaced if any
one item needs replacement.
TIMING GEARS-302 , 332
HD
v-a
AND ALL SD
v-a
CUANING AN D INS PICT ION
C lean the geMS in solvent. Note the
condition of the gear teeth . If the
teeth are scored or the contact pattern
on the teeth is uneven, replace the
gear(s).
It
is good practice to replace
both gears if either gear needs re-
placing.
lACk LASH
Check the backlash between the
camshaft gear a nd the cranksh.art
gear with a dial indicator (Fig. 15).
Hold the gear firml y agai nst the block
while maki ng the check. Refer to the
speci fi cations for Ih.e b:lck lash. limits.
RU NOUT
Check the camshaft and crankshaft
gear runout with a dial indicator (Fig.
16). If the gear runout is excessive,
remove the gear and clean any burrs
from the shafl, or replace the gear
andl or gears.
CAMSHAn AND BEARINGS
CLEANING AND INSPECTION
Clean the camshaft in solvent and
wipe dry. Inspect th.c ca mshaft lobes
for pitting, scoring, and signs of ab-