Ford 1956 Truck User Manual

30
Chapter 1-General Engine Overhaul, Inspection, and Repair
PISTON WEAR CAUSED BY BENT ROD
OR MISALIGNED PISTON
PIN HOLE
6371
Fig. 41-Wear Patlern Dn Piston-P;slon Pin Boss Surface
(4) FITTING PISTON RINGS. Select the proper
ring set for the size piston to be used. B efore the rings
are in stalled on the piston, check each ring for proper
gap as follows:
Position the ring in the cylinder bore in which it is
going to be used. Push the ring down into the bore area
where normal ring wea r is not encountered. Use the head
of a piston to position the ring in the bore so the ring ;s
square with the cylinder wall. Use caution during this
operation to avoid damage to the ring or cylinder bore.
Measure the gap between the ends of the ~ing with a
feel
er gauge (fig. 46). The gap should be from 0. 010.
0.027 inch. If th e gap is less than the lower limit , try
another ring set. After the rings hav e been fitted in the
cylinder bore, immediately install them on the piston or
iden tify them with the piston and cylinder in which they
are to be installed.
After the rings have been installed in the ring grooves
BEARING WEAR
IMPROPE R. GRINDING OF CRANKSHAFT JOURNAL
6372
Fig. 48-Wear Pattern on Connecting Rod Bearing
according to the instructions on the piston ring package,
check the ring side clearance with a feeler gauge. The
gauge s hould slide freely arou nd the entire piston ring
circumference without binding.
If the rings are to be installed in a us ed cylinder,
remove the "gl aze" on the bore as previous ly explained .
(5) FITTING PISTON PIN. The piston pin should
be a light thumb press fit at norma l temperature (70 ° F).
Standard pisto n pins are color coded green. Pins of
0.001 inch overs ize (color coded blue) and 0.002 inch
oversize (co lor coded yellow) are available.
If the piston pin ho le mu st be reamed , u se an expan-
sion-type piloted reamer. Place the ream er in a vise and
revolve the piston around the reamer. Set the reamer to
the size of the pin bore, then expand the reamer slightly
and trial r ea m the pin bore . Take a light cut . Use a p il ot
sleeve of the nearest size to maintain a li gnment of
the bores .
Ch eck the reamed hole size, using the new piston pin.
If t he bore is small, expand the reamer sligh tly and
make another cut. Repeat the procedure until the proper
fit is obtained. Check the fitted piston pin for fit in the
respective rod bushing. Ream the bu s hing if ne cessary
to fit the pin.
Install a retainer at eac h e nd of the pin to hold it in
place. When the r etainers are installed, make sure they
are properly seated in the grooves provided in the piston
pin bore. Always use new retainers.
c. Connecting Rod.
The connect ing rods and re l ate d parts sho u ld be care-
fully
inspected and checked for conforma~ce to specifi-
cations. Va rious forms of engine wear which are caused
by these parts can be readily identified as follows:
A
shiny sur f ace on the pin boss side of the piston
usually indicates that a connecti ng rod is bent or the
piston pin ho le is not in proper re l ation to the piston
skirt and ring gr ooves (fig. 47) .
Abnormal connecting rod bearing wear can be caused
by eit her a bent connecting rod, a crankshaft journal
improperly machined, or a tapered connecting rod bore
(fig. 48).
Twisted connecting rods will n ot create an easily
identifiable wear pattern, but badly twisted r ods will
disturb the n orma l ac tions of the e ntir e piston, ring,
and rod assemb ly that may result in excessive oil
consumptio n.
(1) CLEANING AND INSPECTION. Cl ean all parts
and passages in solvent. N ever use a ca ustic clea ning
solution.
Remove the bearings (id entify them if they
are to be used aga in) , then thorough ly clean the rod bore

Ford 1956 Truck Specifications

General

Brand	Ford
Model	1956 Truck
Category	Automobile
Language	English