Nissan 12010-03P02 Piston W/Pin

Before installing the piston and connecting rod assemblies, ensure the cylinder walls are clean, the top edge of each cylinder is chamfered, and the crankshaft is in place. Remove the connecting rod cap from the number one connecting rod, take out the old bearing inserts, and wipe the bearing surfaces with a clean, lint-free cloth. Clean the back side of the new upper bearing half and lay it in place in the connecting rod, ensuring the tab fits into the recess without hammering or nicking the bearing face, and do not lubricate at this time. Clean the back side of the other bearing insert and install it in the rod cap, again ensuring the tab fits into the recess without applying lubricant. Position the piston ring gaps correctly and slip a section of plastic or rubber hose over the connecting rod cap bolts. Lubricate the piston and rings with clean engine oil, attach a piston ring compressor, and allow the piston skirt to protrude about one-quarter inch to guide it into the cylinder. Rotate the crankshaft until the number one connecting rod journal is at bottom dead center and apply a uniform coat of engine oil to the cylinder walls. With the dot on top of the piston facing the front of the engine, gently place the piston and connecting rod assembly into the number one cylinder bore, resting the bottom edge of the ring compressor on the engine block, and tap the top edge to ensure contact around the circumference. Clean the number one connecting rod journal on the crankshaft and the bearing faces in the rod. Carefully tap the top of the piston with a wooden hammer handle while guiding the connecting rod into place on the crankshaft journal, maintaining downward pressure on the ring compressor to prevent the piston rings from popping out. If resistance is felt, stop immediately to identify and resolve the issue without forcing the piston. After installation, check the connecting rod bearing oil clearance before permanently bolting the rod cap in place by cutting a piece of Plastigage and laying it on the number one connecting rod journal. Clean the connecting rod cap bearing face, install the rod cap ensuring the mating marks align, and tighten the nuts to the specified torque without rotating the crankshaft. Remove the rod cap carefully to avoid disturbing the Plastigage, compare the width of the crushed material to the scale on the container to obtain the oil clearance, and ensure it matches the specified clearance. If not, double-check the bearing inserts and crankshaft journal diameter for cleanliness. Scrape off any Plastigage material carefully, apply a layer of moly-based grease or engine assembly lube to the bearing faces, and push the piston into the cylinder to expose the bearing insert face. Slide the connecting rod back into place, remove the protective hoses, install the rod cap, and tighten the nuts to the specified torque in three steps. Repeat the procedure for the remaining piston and connecting rod assemblies, keeping everything clean and ensuring the correct piston is used with the dot facing the front of the engine. After all assemblies are installed, rotate the crankshaft by hand to check for binding. Check the connecting rod end play using either a feeler gauge or a dial indicator, comparing measurements to the specified end play. If measurements do not agree, verify the bearing inserts and consider replacing rods or the crankshaft if necessary.

Using a piston ring installation tool, carefully remove the rings from the pistons without nicking or gouging them. Scrape all traces of carbon from the crown of the piston using a hand-held wire brush or fine emery cloth after the majority of deposits have been removed. Avoid using a wire brush mounted in a drill motor, as it can erode the soft piston material. Utilize a piston ring groove cleaning tool to eliminate carbon deposits from the ring grooves; if unavailable, a piece broken off the old ring can suffice, ensuring no metal is removed and the sides of the grooves remain undamaged. After cleaning, use solvent to clean the piston/rod assemblies and dry them thoroughly. If the pistons show no excessive damage or wear and the engine block isn't rebored, new pistons may not be necessary, as normal wear appears as even vertical lines and slight looseness of the top ring. Inspect each piston for cracks around the skirt, pin bosses, and ring lands, and look for scoring, scuffing, holes, or burned areas on the piston crown, which may indicate overheating, abnormal combustion, preignition, or detonation. Corrosion evidenced by pitting suggests coolant leakage into the combustion chamber or crankcase, necessitating correction of the underlying issue. Measure the piston ring side clearance by placing a new piston ring in each groove and using a feeler gauge to check the gap, ensuring to compare readings with specified clearances; excessive clearance indicates the need for new pistons. For piston-to-bore clearance, measure the cylinder bore and piston diameters, subtracting the piston diameter from the bore diameter to compute clearance, and compare with specifications; if greater, rebore the block and install new oversize pistons and rings. Assess piston-to-rod clearance by twisting the piston and rod in opposite directions; noticeable play suggests excessive wear, necessitating replacement of the assemblies. Finally, check connecting rods for cracks and damage by temporarily removing rod caps, inspecting bearing surfaces for nicks or scratches, and after checking, replace old bearings and secure the caps.

Protect the crankshaft journal and cylinder wall by slipping a short length of plastic or rubber hose over each connecting rod cap bolt during piston and rod removal.