Genuine Nissan Timing Chain

Nissan Pathfinder Timing Chain Parts Questions & Experts Answers

• Q: How to properly remove and install the timing chain and associated components during an engine timing system service on Nissan Pathfinder?

  A: Ensure the engine is completely cool before commencing this procedure. Removal of components for timing system work should only be attempted by experienced individuals, as errors can result in severe engine damage. Prior to initiating this process, verify your competence or seek professional guidance if uncertain. Begin by relieving fuel pressure and disconnecting the battery. Remove the engine cover, drivebelts, idler pulley brackets, and spark plugs while positioning the number one piston at TDC on the compression stroke. Raise the vehicle's front, secure it on jackstands, and drain the cooling system and engine oil. Proceed to remove the crankshaft sensor, Crankshaft Pulley, air conditioning compressor, air conditioning compressor bracket, upper and lower Oil Pans, upper and lower intake manifold plenums, valve covers, cooling fan, radiator, power steering pump, fan pulley bracket, power steering pump bracket, alternator, and water bypass pipe, marking and detaching hoses as needed. Remove Camshaft and variable valve timing (VVT) sensors from the front timing chain cover, along with the VVT actuator covers, and loosen the cover bolts. Detach the wiring harness from cover brackets and remove the front timing chain cover, ensuring the number one piston remains at TDC. Release tension on the primary timing chain, remove the primary tensioner, tensioner pivot arm/chain guide, and upper timing chain guides. Secure the secondary timing chain tensioners and remove camshaft sprocket bolts before disengaging the primary timing chain from the sprockets. Carefully mark and remove camshaft sprockets and secondary timing chains, taking care not to damage the sensor ring. Remove the crankshaft sprocket and lower timing chain guide, and inspect components for wear. Verify the correct timing chains, counting links and comparing new and old chains. If secondary tensioners were removed, reinstall them and ensure the camshafts have dowels facing up. Install the secondary timing chains and sprockets with timing marks aligned, then remove stopper pins from secondary chain tensioners. Install the primary timing chain on the crankshaft sprocket, water pump sprocket, and primary camshaft sprockets, aligning colored chain links with sprocket marks, and install upper timing chain guides. Install primary tensioner arm/chain guide and timing chain tensioner assembly, making sure the number one piston remains at TDC and timing marks align. Tighten camshaft sprocket bolts, clean and seal front timing chain cover, and install cover bolts, tightening in proper sequence. Place new O-rings in WT orifices and apply sealant to variable valve timing actuator covers, installing them over dowels on front timing chain cover. Reattach the wiring harness and bolts for the front timing chain cover. Install power steering pump bracket and fan pulley bracket if necessary. Complete the installation by following the reverse removal process, adhere to sealant manufacturer recommendations, allow sealant to cure, replace the oil filter, refill oil and coolant, start the engine, and inspect for leaks. Note that timing chain noise may be present temporarily, but it should subside as air is bled from the primary timing chain tensioner's high-pressure chamber.
• Q: How to replace the timing chains in this engine on Nissan Pathfinder?

  A: The timing chain assembly of this engine comprises a lower chain connecting the crankshaft sprocket to an idler sprocket on the Cylinder Head and an upper chain linking the idler sprocket to the two camshaft sprockets. Replacement of these timing chains, although rare as they should last the engine's lifetime, is a complex procedure necessitating the removal of the Oil Pan. To remove the upper timing chain, drain the cooling system, removing the valve cover, power steering pump, upper idler pulley, and camshaft sprockets. Then, proceed to the lower timing chain by first removing the upper timing chain. Remove the distributor, various hoses, and the Crankshaft Pulley/vibration damper, ensuring the engine remains at TDC for the No. 1 piston throughout. Drain the engine oil and remove the oil pan and oil pump pick-up if desired. Take off the lower timing chain cover, tensioner, tension arm, chain guide, oil slinger, and oil pump drive gear. Note that it's more convenient to cut the head gasket flush with the cylinder head if the head needs removal. Inspect components for wear and damage and proceed to installation by aligning the silver-colored link on the lower timing chain with the crankshaft sprocket mark and following a meticulous process involving the idler sprocket, chain guide, tensioner arm, and tensioner to ensure correct tensioning. Apply RTV sealant and install the lower timing chain cover securely. After reassembling various components, including camshaft sprockets and upper timing chain, applying RTV sealant and installing the upper timing chain cover, refill fluids, and run the engine while checking for leaks.