Specifications
NOTE: On one side of the big end of the con-rod
there is a two-digit number which refers to the
weight category. On the other side of the big end
there is a four digit number on both the rod and the
cap. These numbers must both face the camshaft
as well as the recess on the piston crown (Fig. 118).
Lightly heat the piston in oven. Insert piston pin in
position and secure it with provided snap rings.
The Four digit numbers marked on con rod
big end and rod cap must be on the same side
as the camshaft (Fig. 118). After having coated
threads with Molyguard, tighten con rod bolts to 29
N·m (21 ft. lbs.) plus 60°.
INSPECTION—PISTON PIN
(1) Measure the diameter of piston pin in the cen-
ter and both ends.
(2) Piston pin diameter is 29.990 to 29.996mm
(1.1807 to 1.1809 in.).
INSPECTION—CRANKSHAFT JOURNALS
(1) Using a micrometer, measure and record crank-
shaft connecting rod journals, take reading of each
journal 120° apart. Crankshaft journal diameter is
53.84 to 53.955mm (2.1196 to 2.1242 in.).
(2) Crankshaft journals worn beyond limits or
show signs of out of roundness must be reground or
replaced. Minimum reground diameter is 53.69mm
(2.1137 in.).
BEARING-TO-JOURNAL CLEARANCE
Compare internal diameters of connecting rod with
crankshaft journal diameter. Maximum clearance
between connecting rod and crankshaft journals .022
to .076mm (.0008 to .0029 in.).
CYLINDER WALL LINER ASSEMBLY
INSPECTION
The cylinder walls should be checked for out-of-
round and taper with dail bore gauge. The cylinder
bore out-of-round is 0.100 mm (.0039 inch) maximum
and cylinder bore taper is 0.100 mm (0.0039 inch)
maximum. If the cylinder walls are badly scuffed or
scored, new liners should be installed and honed, and
new pistons and rings fitted.
Measure the cylinder bore at three levels in direc-
tions A and B (Fig. 120). Top measurement should be
10 mm ( 3/8 inch) down and bottom measurement
should be 10 mm ( 3/8 inch.) up from bottom of bore.
Fig. 117 Connecting Rod Identification
Fig. 118 Piston and Connecting Rod Assembly
Fig. 119 Bearing Clearance
9 - 56 ENGINE WJ
CLEANING AND INSPECTION (Continued)