TUBE AS 2039048 - Caterpillar

(1) Crown assembly.(2) Connecting rod. Install connecting rod and piston group with number on tab groove side of connecting rod to be positioned toward opposite side of engine from camshaft.(3) Piston skirt. Top And Intermediate RingThe 1U6431 Keystone Piston Ring Groove Gauge is necessary for measuring ring grooves in keystone style pistons. For correct use of the gauge group, see the instruction card that is with the gauge group.Install piston rings with "UP" side toward top of piston.(4) Top Ring has the mark "UP-1".(5) Intermediate ring has the mark "UP-2".Clearance between ends of piston ring when installed in a cylinder liner with a bore size of 137.16 mm (5.400 in):Top ring ... 0.724 0.190 mm (.0285 .0075 in)Intermediate ring ... 1.080 0.190 mm (.0425 .0075 in)Increase in clearance between ends of piston rings for each 0.03 mm (.001 in) increase in cylinder liner bore size ... 0.08 mm (.003 in) Oil Control Ring(6) Install oil control ring with the gap in the spring 180 degrees away from the gap in the ring. White portion of spring must be visible at the ring end gap.Width of groove in piston for piston ring (new) ... 3.210 0.010 mm (.1264 .0004 in)Thickness of piston ring (new) ... 3.137 0.013 mm (.1235 .0005 in)Clearance between groove and piston ring (new) ... 0.051 0.025 mm (.0020 .0010 in)Maximum permissible clearance (worn) ... 0.15 mm (.006 in)Clearance between ends of piston ring when installed in a cylinder liner with a bore size of 137.16 mm (5.400 in) ... 0.572 0.190 mm (.0225 .0075 in)Increase in clearance between ends of piston ring for each 0.03 mm (.001 in) increase in cylinder liner bore size ... 0.08 mm (.0003 in) Piston Pin Bore(7) Pin bore diameter in piston crown bearing ... 55.047 0.008 mm (2.1672 .0003 in) Pin bore diameter in piston skirt ... 55.013 0.004 mm (2.1659 .0002 in)Pin diameter ... 55.000 0.005 mm (2.1654 .0002 in)Thoroughly lubricate pin with clean engine oil before assembling to piston group and connecting rod.