Cadillac 54-6219 1954 Shop Manual page 188

:1,-Il
ENGINE MECHANICAL
NOTe: °ii'ne-., pins are a n:otch fIt to the
piston and ate nom available separatety
-
Piston
pins will not become loose enough tu cause
a
knnck or tappiug until after very high mileages
sod in such cases a new pi emit and pIll assembly
shoutd be :nstalled.
24 Measuritig Piston Clearance
Piston should he measured for size I /3' beluw
the upper cross slot and at rIght angles to piston
pill. Cylinders shollld he Ineasored t-t/4'' from
he roil. ,:ros swi
5
e to the cyl iluder tulock
The clearame :'l:et,ld be .OfIIi7'' to .0011'' in this
position a; 'i F0 Subtract .11101'' from measure-
meult for e,vers: 6
shave 711°F.
At the Kactory. a system of letters stamped no
the top face of ml IC block, either to the night n r left
of each cylinder hire, tIc! , u ot cc the c 3 ira dat sizes
as shown below;
Letter Cylinder Sizes
Pi.stou Sizes
A 3.8115-33127
3.Stta-3.sIl8
B 3.B127-3 8114 38118-38110
C 3.8129-3.8131
3.8120 -3.8121
U
38131-38133 3.3122-38124
E 3.8 t,B:3-.S h135 3312,1-38 t26
H
3.8135-3.8137
3 .8t16-S .8118
J
3.8t37-3.8130 3,8128-.3.8I30
K 3.8 t39-3.8141 3.8130-3.3132
L
3,814t-3fl43 3.8132-3.8134
M 3.81 433 8145
3.8134-3.3136
The rl,sm't i,ldicl:e a
tel:
c',li.::'jcr
.IIzc,s I: 5T1
he
rahi,;c'
of .':i;I''
. '
Pt:c'rc
:tr'
t',..:e,:tv size;,
ever, ,,e a_Ic'' let,::r is t'nhicr'-'' or ''-''.if lie
letter is su,;uiil:e.d no utic left
.'.,,'
the cri:ndcr, it
If letter is stauiiped to the right of cvii,:der,
ii is
''_''
I 'lm'r:,k-es it
rlc,iu-ou:c
0!
iI .i;i':Ii,- .,a,22
'',,i:;
:::,mnerly 'it,iIe_I.
Foe- servici'- one, punt::n .s:ure ft,mnIe.:o,_:, it, the'L''
or'fT' code
,I7,os
only
if
a
double letter ''AA'', appears eIther to the
left or raght of the cylInder it indicates that the
cylinder has been bored to .010'' over ;he dia
meter i,idieaued by the iettec In the chart. Ftec
example, a cvlir:ricr ',r:th ihe letters ''CC'' stamped
Ola the block to the left of the cylinder would
have a &amnL'ter ot 3.8129'' * .1110'' or 3.8229''
and a pls:on diurneter 0138214''
Replaceusieuit pistons ate furnished by the iac
-
to my
I :a rts
Dei,a rE mont
iii
the ft' 110w ctg sizes;
Stamldard
.011'' oversIze
.010'' oversfze
.0 30' eve ra i
7,:'
Piston diameters, as gIven in rUe specification
table, call be measured wIth, a large micrometer,
:1.5
silewr, in l7ig. IL' -25.
Before ordering pisto:us for replacement, It
is cx trenis ly uiipo r ta ! u
I
to dc-ut', rot 'to t
Ije
size of
the cylinder bores by actual measuremeust. Actual
measurement at the timie of replacemeuut is rIot only
certain way to a v:,,id errors in nrdering.
Fig.
0-24 Inutnlli.ig
P11101,
Pin in Piston nod
Cnnuwctiuug
Rod