Genuine Nissan Armada Valve Stem Oil Seal

Nissan Armada Valve Stem Oil Seal Parts Questions & Experts Answers

• Seal-Oil,Valve
  13207-3Z000
  Q: How can broken valve springs and defective valve stem seals be replaced without removing the cylinder heads on Nissan Armada?

  A: Broken valve springs and defective valve stem seals can be replaced without removing the Cylinder Heads, typically requiring two special tools and a compressed air source. Begin by removing the valve cover(s) and the camshafts and lifters from the affected cylinder head. Remove the spark plug from the cylinder with the defective component, and if replacing all valve stem seals, remove all spark plugs. Turn the crankshaft until the piston in the affected cylinder is at Top Dead Center on the compression stroke, working on one cylinder at a time following the firing order. Thread a long adapter into the spark plug hole and connect an air hose from a compressed air source, using a long spark plug adapter with a length of hose attached. Apply compressed air to the cylinder and stuff shop rags into the cylinder head holes around the valves to prevent parts and tools from falling into the engine. Use a valve spring compressor to compress the spring, releasing the valve stem keepers and lifting them out with a magnet or needle-nose pliers. Remove the spring retainer and valve spring, then the valve stem seal. Wrap a rubber band or tape around the top of the valve stem to prevent it from falling into the combustion chamber, then release the air pressure. Inspect the valve stem for damage, ensuring it doesn't bind in the guide; if it does, the cylinder head will need to be removed for repair. Reapply air pressure to retain the valve in the closed position, then remove the tape or rubber band. Lubricate the valve stems with engine oil and install new valve stem seals, using a special tool or a deep socket and hammer to seat them. Install the valve spring over the valve with the more closely-wound coils and paint mark toward the cylinder head, followed by the valve spring retainer. Compress the valve springs and position the keepers in the groove, applying a small dab of grease to hold them in place. Remove the pressure from the spring tool and ensure the keepers are seated, then disconnect the air hose and remove the adapter from the spark plug hole. Reinstall the camshaft and lifters, then the timing chain, followed by the valve covers. Finally, install the spark plug(s), ignition coils, and the upper and lower intake plenum as necessary, start the engine, and check for oil leaks and unusual sounds from the valve cover area.