by placing them in a sleeve, square them up in the bore with a piston, and measure the gap with a feeler
gage. The piston ring gap should not be less than 0.015 inches.
(4) Check the piston pin to connecting rod bushing clearance. This should be from 0.0007 to 0.0012 inches. If
this clearance is more than 0.0012 inches, press out the bushing in an arbor press (par. 179) and install a
new bushing.
(5) Roll each piston ring in its groove and check the side clearance in several locations. Refer to figure 104 for
correct ring position. The side clearance for each ring is as follows: Top groove ring (10, fig. 104), 0.0020 to
0.0045 inch; second groove ring (9), third groove ring (7), and oil control ring (6), 0.0015 to 0.0035 inch. Do
not use a ring whose side clearance is greater than the maximum.
c. Reassembly and Installation (fig. 104).
(1) Press new piston pin bushing (12) into the connecting rod (3). Use an arbor press (par. 179) for this
purpose.
(2) Install the piston rings (6, 7, 9, and 10) with a piston ring expander (par. 179) spreading the gap only enough
to slide them into place. Start with the oil control ring (6) and proceed to the top of the piston. Put the
expander (8) in the third ring groove before installing the third groove ring (7). Heat the piston (5) in warm
water, locate the piston T-slot and connecting rod (3) in their original relative position, then insert the piston
pin (11) with a very light tap. Put in the pin retainers (4).
(3) Put the connecting rod bolts (13) through their connecting rod holes. Coat the cylinder walls with clean
engine oil. Place piston ring compressor (par. 179) over the top of the piston and apply enough pressure to
compress the rings so the piston is snug. Insert the piston assembly into the cylinder bore. Check to see
that the side of the connecting rod with the least chamfer faces the adjacent connecting rod, and the T-
slotted side of all pistons face towards the engine bank. Guide the piston into the bore with the ring
compressor, releasing the tension enough to allow the piston to enter the bore without binding of the rings.
(4) Clean the backs of the bearing shells (2), lubricate their surfaces with engine oil, and install them in the
connecting rod. Position the connecting rods on the crankshaft.
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