GM 12646457
Pistons, Green Line

Engine repair technicians start replacement of Piston connecting rod and bearing within a 2.2l engine by removing both the Oil Pan and Cylinder Head. A ridge reamer must be used to remove the ring ridge first by placing the Piston at the bottom stroke with Crankshaft rotation while placing a cloth over it. Use the Crankshaft to lift the Piston stroke and remove the fabric material with debris before making identifying marks for final reinstallation. The processing begins with removal of the connecting rod nuts and cap followed by disposal of the bolts and nuts before extracting the connecting rod and Piston with the j-41742 (Connecting Rod Guide Pin) and j-43966-1 (Connecting Rod Guides). Clean your cylinder bores by hot water soapy solution or light honing until they are free from residue then apply engine oil using a dry clean cloth for swabbing. You must first coat the Piston Ring compressor with engine oil before installing the Piston into its original bore with the help of j-43966-1 (Connecting Rod Guides) and j-43953 (Piston Ring Compressor) as well as j-41742 (Connecting Rod Guide Pin). Use a wooden hammer handle to carefully strike the Piston while maintaining the stamped mark orientation toward engine front. Once the Piston rings enter the bore put the j-43953 (Piston Ring Compressor) against the block and follow by installing the connecting rod caps to their respective rods by matching the prior numbered indicators. The procedure requires new connecting rod bolts and nuts which need proper distribution of torque at 25 nm (18 lb ft) for the first stage before moving to 100 degrees utilization of the j-45049 (Angle Meter) in the last stage. To check the connecting rod side clearance professionals must use a feeler gauge which should show measurements from 0.070-0.370 mm (0.0027-0.0145 in). The final operation should include reinstalling both the Cylinder Head and the Oil Pan.

Before replacing the Piston alongside connecting rod and bearing you must take out the Oil Pan together with the Cylinder Head. The Crankshaft needs to rotate until the Piston reaches its lowest position before placing a cloth on top of the Piston for using a ridge reamer which will eliminate the ring ridge. Once the Crankshaft reaches its top position remove the debris and cotton material. Use a marker to identify connecting rod and cap positions for later reinstallation before you take out connecting rod nuts and cap while discarding both items. The (J-43966-1) tool will help extract connecting rods and Piston pieces from the block. Clean the cylinder bores with hot water solutions of detergent or light honing before using engine oil followed by cleansing with a clean cloth. Use engine oil to coat the Piston along with its rings together with the cylinder bore and bearing surfaces before installing the Piston through its original bore with the (J-43966-1). Lightly tap the Piston top using a wooden hammer handle. Position the Piston stamping toward the front engine direction and apply the (EN-47836) device to the engine block to guide pistons into the bore before putting on connecting rod caps that match the previously noted rod numbers. Use even torque when tightening new connecting rod bolts and nuts to 25 nm (18 lb ft) before continuing with a second tightening sequence of 100 degrees through the use of the (J 45059). Create a side clearance measurement of the connecting rod by using a feeler gauge to verify values between 0.070-0.370 mm (0.0027-0.0145 in). The procedure ends with reinstallation of both the Cylinder Head and the Oil Pan.

The first step to replace a Piston with its connecting rod along with a bearing requires workers to remove both the Oil Pan and the Cylinder Head. The first step requires moving the Crankshaft while watching the Piston to reach the lowest point and placing fabric directly above it. At this position you should utilize a ridge reamer to eliminate the ring ridge. Next turn the Crankshaft to its top stroke position while disposing the cloth and cutting debris before making connecting rod and cap markings for reassembly. You should begin by removing the connecting rod nuts and cap followed by bolt and nut disposal. Proceed with extracting the connecting rod and Piston from the engine block through the usage of connecting rod guides (J-43966-1). Detergent-hot water mixture or light honing should be used to clean cylinder bores while a mixture of engine oil and a clean dry cloth should follow for wiping the bore surfaces. Place engine oil on the Piston as well as the Piston rings and cylinder bore and bearing surfaces before using the connecting rod guides (J-43966-1) to install the Piston correctly into its original bore while gently tapping its top with a wooden hammer handle. Aligning the marked Piston stamp with the front of the engine requires the use of the Piston Ring compressor (EN-47836) to clamp the engine block until all Piston rings reach the cylinder bore. After that, install connecting rod caps on their correct connecting rods while maintaining their prior number alignment. New connecting rod bolts and nuts require even nut tightening to 25 n.m (18 lb ft) first then the angle meter (J 45059) completes the final tightening process to 100 degrees. A feeler gauge should measure the connecting rod side clearance at 0.0027-0.0145 in (0.070-0.370 mm) after which you can install the Cylinder Head before putting on the Oil Pan.

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

The caps must be reassembled to their original rods.

Remove the connecting rod nuts and cap, discard the bolts and nuts, and extract the connecting rod and piston using the J-43966-1.