GM 19180242
Pistons

An Oil Pan followed by a Cylinder Head must be removed before beginning the Piston connecting rod bearing replacement. A ring ridge needs removal so turn the Crankshaft to place the Piston in the bottom position before using a ridge reamer on top of the Piston while it is covered by a cloth. Proceed by rotating the Crankshaft to its peak stroke position before removing the cloth as well as the debris while preparing to record the connecting rod and cap assembly order. Next remove the connecting rod nuts and cap, discard the bolts and nuts then extract the connecting rod and Piston from the engine block by using (J 41742) and (J-43966-1). Heat the cylinder bores by washing them with hot water and detergent before treating them with oil and drying them with a clean cloth. Place engine oil on pistons together with rings and bores and bearings before fitting pistons into their original location with (J-43966-1), (J 43953) and (J 41742). Strike the Piston top gently with a wooden hammer handle in a way that features the stamped Piston mark aimed at the engine front. Retain (J 43953) against the motor block to let all rings pass into the barrel while you install the connecting rod caps onto their original connecting rods according to marked numbers. Use (J 45059) to achieve 100-degree extra tightening on the last pass after initial equal bolt torquing to 25 nm (18 lb ft). You must check the connecting rod side clearance with a feeler gauge as it should fall within the range of 0.070-0.370 mm (0.0027-0.0145 in). The last step includes adding the Cylinder Head together with the Oil Pan.

Clean the cylinder bores with hot water and detergent or light honing, then swab with engine oil and a clean, dry cloth.