GM 96067709 Piston Kit, Std Mark 2

The piston/connecting rod assemblies should be removed after the cylinder head, the oil pan and the oil pickup have been taken out. Use your fingernail to determine if there is a ridge or not at the upper limit of ring travel (about 1/4-inch down from the top of each cylinder). If a ridge has formed due to carbon deposits or cylinder wear it must be removed completely with a special ridge reamer tool. Follow all directions given by the manufacturer of the tool. It is important to remove these ridges before attempting to remove piston/connecting rod assemblies as failure to do so may cause piston breakage. Turn engine upside down so that crankshaft faces upwards once all ridges are removed from cylinders. Check end play with feeler gauges before removing connecting rods. Slide them between first connecting rod and crankshaft throw until play is removed from feeler gauge(s). End play equals thickness of feeler gauge(s). When end play exceeds its service limit, new rods will have to be used. The installation of new rods (or new crankshaft) may cause this value to fall below minimum specified. Repeat steps for other connecting rods. Look for identification marks on the connecting rods and caps. If they are not marked clearly then use a small center punch to make an appropriate number of indentations on each rod and cap (1, 2, 3 or 4 depending on which cylinder it belongs to). Loosen each nut on the connecting rod cap nut by half-turns until they can be unscrewed by hand safely. Remove bearing insert and number one connecting rod cap. Do not let bearing insert slip out of cap. To prevent nicking or gouging the crankshaft journal and cylinder wall while piston is being removed, place a short length of plastic or rubber hose over each connecting rod cap bolt. Through the top of engine push out both bearing insert and connecting rod/piston assembly. Use a wooden hammer handle to push on the upper bearing surface in the connecting rod. If ridge is still present in a cylinder, repeat steps for other cylinders. After removal, reassemble connecting rod caps and bearing inserts in their respective connecting rods and install cap nuts finger tight. The old bearing inserts should be left in place until reassembly to prevent accidental nicking or gouging of the connecting rod bearing surfaces. Don't separate the pistons from their connecting rods.

Before installing the piston/connecting rod assemblies, it's important to ensure that the cylinder walls are clean and that the top edge of each cylinder is chamfered. Additionally, the crankshaft must be in place.