Tracker Off-Road XTR1000 Service Manual page 51

SNO-658A
Measuring Piston Pin Bore Diameter
NOTE: It may be necessary to use Piston Pin Puller

to remove the piston pins.
1. Insert an inside dial indicator into the piston-pin
bore. Take two measurements to ensure accuracy.
2. Piston pin bore must be within 21.003-21.013 mm
(0.8269-0.8273 in.).
SNO-291
Measuring Piston Pin Diameter
Measure the piston pin diameter at each end and in the
center. Measurement must be within 20.990-20.995 mm
(0.8264-0.8266 in.). If measurement is not within specifi-
cations, the piston pin must be replaced.
SNO-292
Installing Piston Rings
1. Install the piston rings according to the illustration
below. Stagger the end gaps of the upper and lower
thin oil rings until they are on directly opposite sides
of the piston.
50
SNO-293A
NOTE: Be sure to install the piston rings so that the

manufacturer marks (A) face up.
2. Rotate the rings until the ring end gaps are 120° from
one another.
SNO-294A
CAUTION
Incorrect installation of the piston rings will result in
engine damage.
CRANKSHAFT RUNOUT
1. Support the crankshaft using a set of V Blocks; use a
dial indicator to read crankshaft runout.
NOTE: The contact point of the dial indicator

should be on either side of the oil port hole of the cen-
ter crankshaft journal and to the outside of the oil
port hole on the MAG and PTO end of the crank-
shaft.
2. Rotate the crankshaft slowly.
3. The reading must be 0.03 mm (0.0012 in.) or crank-
shaft repairing/replacing will be necessary.
MEASURING CRANKSHAFT MAIN/ROD
JOURNALS (Bearing Surfaces)
1. Using a micrometer, measure each main and con-
necting rod bearing journal from along its length and
90° from the first measurement. Measurement must
be within 36.976-37.000 mm (1.4557-1.4567 in.)
diameter for the crankshaft main journal and
37.976-38.000 mm (1.4951-1.4961 in.) diameter for
connecting rod journal.