Table of Contents
Advertisement
•
5.2L/5.9L ENGINE
9 - 55
3.969 T O 3.974-
THE ELLIPTICAL SHAPE OF THE
PISTON SKIRT SHOULD BE .011
(.279 mm) TO .013 (.330 mm) IN.
LESS AT DIAMETER (A) THAN
ACROSS THE THRUST FACES AT
DIAMETER (B)
DIAMETER (D) SHOULD BE
.0000 TO .0005 (.0152 mm)
IN. LARGER THAN (C)
RR09B140
Fig. 3 Piston Measurements—5.9L
Engine
FINISHED
PISTONS
A l l pistons are machined t o t h e same w e i g h t i n
grams, regardless o f oversize, t o m a i n t a i n p i s t o n b a l -
ance. F o r cylinder bores w h i c h have been honed or
bored new pistons are furnished w i t h f i t t e d pins,
available i n standard a n d t h e f o l l o w i n g
oversize:
0.508 m m (0.020 inch).
FITTING
PISTONS
Piston and cylinder w a l l m u s t be clean a n d dry.
Specified clearance between the piston and t h e c y l i n -
der w a l l is 0.0127 t o 0.0381 m m (0.0005 t o 0.0015
inch).
Piston diameter should be measured a t t h e top o f
s k i r t 90° t o piston p i n axis. Cylinder bores should be
measured halfway down the cylinder bore a n d trans-
verse to the engine crankshaft center line.
Pistons a n d cylinder bores should be measured a t
n o r m a l room temperature, 21°C (70°F).
PISTON
PINS
O n both t h e 5.2L and 5.9L engines, the p i s t o n p i n
rotates i n t h e piston only, and i s r e t a i n e d b y t h e
press interference f i t of the piston p i n i n t h e connect-
i n g rod.
FITTING
RINGS
(1) Measure piston r i n g gap about t w o inches f r o m
b o t t o m of cylinder bore i n w h i c h i t is t o be f i t t e d . ( A n
i n v e r t e d piston can be used to push the r i n g s d o w n t o
i n s u r e p o s i t i o n i n g r i n g s squarely i n t h e c y l i n d e r bore
before measuring).
(2) Insert feeler stock i n t h e gap. T h e r i n g gap
should be between 0.254 and 0.508 m m (0.010 a n d
0.020 inch) for compression rings a n d 0.381 t o 1.575
m m (0.015 t o 0.062 inch) for o i l r i n g steel r a i l s i n
standard size bores (for new service rings). M a x i m u m
gap i n 0.127 m m (0.005 inch) O/S bores s h o u l d be
0.907 m m (0.036 inch) for compression r i n g s a n d
1.778 m m (0.070 inch) for o i l r i n g steel rails.
(3) Measure side clearance between piston r i n g and
r i n g l a n d (Fig. 4). Clearance should be 0.038 t o 0.076
m m (0.0015 t o 0.003 inch) for t h e t o p compression
r i n g and t h e intermediate r i n g . Steel r a i l service o i l
r i n g should be free i n groove, b u t should not exceed
0.127 m m (0.005 inch) side clearance.
PISTON RING
FEELER GAUGE
Fig. 4 Measuring
Piston Ring Side
Clearance
(4) O n both the 5.2L and 5.9L engines, the keys on
the spacer expander m u s t be inserted i n t o the hole i n
the o i l r i n g groove over t h e piston p i n front boss
(Fig. 5).
(5) A r r a n g e o i l r i n g r a i l gaps on inboard side of
piston as shown a t top o f (Fig. 5).
(6) I n s t a l l compression r i n g s i n m i d d l e a n d top
grooves; use R i n g I n s t a l l e r Tool C-3586 for 5.2L en-
gines, and Tool C-3562 for 5.9L engines or C-4184 for
both engines. Be sure the identification m a r k (a d r i l l
point, stamped letter O, oval depression or w o r d top)
on each compression r i n g is t o the top o f the piston
when r i n g is installed.
CRANKSHAFT IDENTIFICATION
A crankshaft w h i c h has one or more connecting rod
or m a i n bearing j o u r n a l s undersize w i l l be stamped
w i t h 1/4" letters on t h e m i l l e d f l a t o n t h e N o . 8
crankshaft counterweight on 5.2L crankshafts a n d on
the No. 3 crankshaft counterweight o f t h e 5.9L
crankshafts (Fig. 6).
R X
indicates A L L r o d j o u r n a l s are 0.254 m m
(0.010 inch) undersize; M X indicates A L L m a i n jour-
nals are 0.254 m m (0.010 inch) undersize.
BALANCE OF V8 ENGINE DAMPER, CRANKSHAFT
AND TORQUE CONVERTER
The 5.9L engines have external crankshaft bal-
ance. E x t e r n a l balance is identified b y the off-center
weight cast i n t h e v i b r a t i o n damper h u b a n d t h e
Advertisement
Table of Contents
