The engine must be removed from the vehicle for the following procedure, so ensure you have the proper tools and equipment before beginning. Start by removing the timing chains and sprockets, taking care not to disturb the crankshaft from TDC on the compression stroke of the No. 1 cylinder. Next, remove the intake manifold and the exhaust manifolds, followed by the upper and lower oil pans. Proceed to remove the timing chain, camshafts, and lifters. Using a breaker bar and the appropriate sized Allen-head socket, loosen the cylinder head bolts in 1/4-turn increments until they can be removed by hand, ensuring to loosen them in reverse order of the tightening sequence to avoid warping or cracking the head. Discard the bolts and obtain new ones for reassembly, then lift the cylinder head off the engine block, prying carefully if it is stuck. Remove all external components from the head for thorough cleaning and inspection. When installing the cylinder head, ensure the mating surfaces of the cylinder head and block are perfectly clean, using a gasket scraper to remove all traces of carbon and old gasket material, followed by cleaning with brake system cleaner. If oil is present on the mating surfaces, the gasket may not seal correctly, leading to leaks. Stuff the cylinders with clean shop rags to keep out debris and use a vacuum cleaner to remove any material that falls into the cylinders. Check the block and head mating surfaces for nicks, deep scratches, and other damage, using a file for slight damage or considering machining for excessive damage. Use a tap of the correct size to chase the threads in the head bolt holes and clean them with compressed air. Inspect the head gasket surface of the head and the intake and exhaust manifold surfaces for any signs of damage, corrosion, cracks, or surface irregularities. Reinstall any components that were removed from the head, position the new cylinder head gasket over the dowel pins on the block, and carefully set the head on the block without disturbing the gasket. Before installing the new cylinder head bolts, apply a small amount of clean engine oil to the threads and the underside of the bolt heads, then install the bolts and tighten them finger tight. Tighten all the bolts in several steps to the specified torque. Remove all traces of old sealant from the rear timing chain cover and the cover bolts, then apply a bead of RTV sealant to the timing chain cover sealing surfaces to the block and heads, and install new O-rings in the front of the engine block and timing chain covers. Install the camshafts, then the timing chains and sprockets, with the remaining installation steps being the reverse of removal. If any part of the valve train was replaced, check and adjust the valve clearance. After the engine has been installed, change the engine oil filter, then add oil and coolant. Finally, start the engine and check for oil and coolant leaks.
Posted by NissanPartsDeal Specialist 
