Ford 1956 Truck User Manual

Section 6- Timing Chain and Sprockets, Timing Gears, and Camshaft
23
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 the same plane as the push rod move-
ment (fig. 25). Rotate the engine slowly until the
tappet is on the heel of the cam lobe. Zero the dial
indicator, then continue to rotate the engine slowly until
the pU'ih rod is in the fully raised position. Compare
th e total lift recorded on the indicator to specifications.
Continue to rotate the engine until the indicator reads
zero. This later step is a check on the accuracy of the
original indicator reading.
(2) INSPECTION. Thoroughly check the camshaft
for cracks. Ex amine the lobes for pitting, scoring, and
signs of abnormal wear. Check the lobes with a microm-
ete r. Suspected worn lobes should be compared with a
good
lobe to be sure diagnosis is correct. Measure the
journal diameter for wear and out-of-roundness. Measure
the I.D. of the camshaft bearings. If the clearances are
excessive the cam and/or cam bearings should be re-
placed . Check the fuel pump eccentric for wear.
(3) Rt:PAIRS. Replace all camshafts that are dam·
aged beyond repair. Remove light scuffs, scores, or
nicks with a hard Arkansas stone, then polish with
crocus cloth .
The lobe wear characteristics may result in pitting
in the general area of the nose portion of the lobe. This
pitting is not detrimental to the operation of the cam
if the initial cam lobe lift loss has not exceeded 0.005
inch. The camshaft will continue to operate satisfactorily
for the normal life expec tancy of the engine without
noticeably affecting engine performance. Therefore, cam-
sha fts shou ld not be replaced unless the lobe lift loss
exceeds the above specification or the tappet contact
face shows evidence of failure.
Fig. 29-Camshaft End Play Check-Typical
Normally, if the front journal to bearing clearance
is excessive, it can be assumed that all bearings are worn
and need replacement.
If any of the teeth on the distributor drive gear are
broken or worn, it will be necessary to replace the
camshaft.
(4) CAMSHAFT END PlAY CHECK. Push the
camshaft toward the rear of the engine . Place a dial
indicator point against a suitable surface on the front
end of the camshaft assembly (fig. 29). Set the dial to
zero, then pull the camshaft forward and release it.
Compare the dial reading with specifications .
If the end play is excessive, check the spacer for
correct installation. Replace the thrust plate and/or
spacer if necessary.
7. FLYWHEEL, CRANKSHAFT, AND MAIN BEARINGS
Procedures for the inspection and repair of these
components are given here. In addition, procedures for
fitting
main bearings, thrust bearing alignment, and
replacing the rear main bearing crankshaft oil seal are
given.
a. Flywheel.
The flywheel and ring gear are a shrink fit and are
replaceable as separate parts .
(1) INSPECTION. Check the flywh eel face .unout
with a dial indic a tor (fig. 30). Be sure to hold the fly.
whee l full forward or rearward so that the crankshaft
end play will not be indicated as flywheel runout. If
the runout is excessive, remove the flywheel, and check
the runout of the crankshaft mounting flange. It will be
necessary to remove the crankshaft if the flange requires
machining.
Inspect the ring gear for worn, chipped or cracked
teeth. Check the ring gear runout as indicated in fig. 31.
(2) REPAIRS. If the flywheel runout is excessive and
the flange is not at fault, replace or machine the flywheel.
Machine the friction surface of the flywheel if it is
scored or worn. If it is necessary to remove more than
0.045 inch of stock from the original thickness, replace
the flywheel.
If the ring gear teeth are damaged and unfit for
further use, or if the runout is excessive, replace the
ring gear as follows:
Heat the defective ring gear with a blow torch on the
engine side of the gear, then knock it off the flywheel.

Ford 1956 Truck Specifications

General

Brand	Ford
Model	1956 Truck
Category	Automobile
Language	English