Cylinder Block; Cylinder Bores; Measuring Cylinder Bore With Bore Gauge; Normal Cylinder Bore Wear Pattern - Jeep J-10 Series 1982 Technical & Service Manual

Installation
(1) With upper main bearing inserts installed, posi
tion replacement crankshaft in block.
(2) Install main bearing caps (with lower bearing
inserts), but do not tighten cap bolts. Oil bearings prior
to assembly.
(3) Move connecting rods (with upper bearing in
serts installed) and pistons into place.
(4) Install rod bearing caps (with bearing inserts),
but do not tighten nuts. Apply oil to bearings prior to
assembly.
(5) With rubber mallet, strike both ends of crank
shaft to center thrust bearing. Rearward first, forward
last.
(6) Tighten main bearing caps (65 foot-pounds, 88
N«m), then measure crankshaft end play. It should be
between 0.0015 inch (0.038 mm) and 0.0085 inch (0.216
mm).
(7) Tighten connecting rod bearing caps (30 foot
pounds, 40 N«m).
(8) Measure bearing clearances using Plastigage
method.
(9) Install key from original crankshaft in replace
ment crankshaft keyway.
(10) Install crankshaft timing gear and ALIGN TIM
ING MARKS ON TIMING GEARS BY ROTATING
CRANKSHAFT, IF NECESSARY.
(11) Install timing case cover using replacement seal
and gaskets.
(12) Install oil pump assembly and oil pan using re
placement rear seal in rear main bearing cap and re
placement front seal for timing case cover. Press front
seal tips into holes in timing case cover.
(13) Coat front cover oil seal contact area of vibra
tion damper hub with oil and push into position.
(14) Install fan pulley and fan.
NOTE: The fan assembly and pulley must be installed
with the drive belt(s) in position on pulley.
(15) Install spark plugs.
(16) Remove engine from stand.
(17) Install engine in vehicle.
CYLINDER BLOCK
The cylinder block is manufactured from cast iron and
has 4 in-line cylinders that are numbered from front to
rear, 1 through 4. Five main bearings support the crank
shaft, which is retained by recessed bearing caps that
are machined with the block for proper alignment and
clearances.
The cylinders are completely encircled by coolant
jackets. (For details of engine cooling system, refer to
Chapter 1C—Cooling Systems.)
Cylinder Bores
Inspect cylinder bores for out-of-round or excessive
taper with an accurate Cylinder Measurement Gauge
ENGINES 1B-25
Tool J-8087, or equivalent. Measure at top, middle and
bottom of bore (fig. 1B-40).
Measure cylinder bore parallel and at right angles to
the centerline of the engine to determine out-of-round-
ness. Variation in measurement from top to bottom of
cylinder indicates the taper in the cylinder. Figure 1B-41
illustrates the areas in the cylinder bore where wear
-
80304
Fig. 1B-40 Measnrlng Cylinder Bore Witt Bera Gauge
normally occurs. If dimension A is larger than dimen
sion B by 0.002 inch (0.051 mm) or more, it indicates the
necessity for cylinder boring and installing replacement
rings and pistons. Cylinder bores can be measured by
setting the cylinder measurement gauge dial at zero in
the cylinder bore at the location of desired measure
ment. Lock dial indicator at zero before removing from
cylinder bore, and measure across the gauge contact
points with outside micrometer (with the gauge at the
same zero setting when removed from the cylinder).
2-1/4
Fig. 1B-41 Normal Cylinder Bore Wear Pattern
90891