Toyota 90080-31043 Engine Valve Stem Oil Seal

Malfunctioning valve springs and valve stem seals can usually be replaced with the cylinder head still on the engine; usually, doing so requires the use of two specialty tools and a source of compressed air. To start with, you should pull off the valve cover with the assistance of a ratchet; secondly, eliminate the timing chain, the camshafts and the lifters of the cylinder head. If replacing all valve stem seals, the remove all spark plugs or if fixing a single cylinder, rip out the spark plug. Rotate the crankshaft until the piston in the problematic cylinder is at TDC on the compression stroke, proceed with one cylinder at a time based on the firing sequence. Insert an adapter into the spark plug hole and tap the socket end of an air hose connected with a compressed air can. Use compressed air to close the valves within the cylinder to keep the valve tight in its position and jam shop rags into the cylinder head opening around the valves in order to avoid an ingress of the remnants into the engine. Strike the top of each valve spring retainer lightly with a hammer and then rotate a valve spring retainer around which you can see small notches to unlock the keepers from them Then, use the valve spring compressor to compress the spring and remove the keepers. Be certain to use the correct type of valve spring compressor that screws on top of the cylinder head. Take of the valve spring and retainer, therefore if air pressure cannot hold the valve shut, it will close on the face or seat thereby requiring the head to be off to do the necessary repair. Take off the old valve stem seals distinguishing between the intake and the exhaust ones, then, having squeezed in the air, wind the top of the valve stem with the help of a rubber band or a piece of tape so that the stem fails not to fall down into the combustion chamber. Feel the lead of the valve stem to check for binding, if the stem rotates in the guide with binding, then either the valve was bent or the guide is bad and would necessitate head removal. Apply pressure in the air to hold the valve closed, and coat the valve stem with the engine oil, then fit a new and suitable seal onto the valve guide. Place the valve spring and the spring retainer over the valve, then place your thumb on the opened end of a keep in the groove and push it to the other end of the groove while applying small amount of grease on the keepers to easily fit it. After tightening the bolt on the keepers, deflate the pressure of the spring tool and drop it out, disconnecting the air hose and withdrawing the adapter from the spark plug hole. Next, replace the camshaft, lifters, the timing chain, and the valve cover, then the spark plugs and ignition coils, after that, start the engine and look for oil leaks and strange sounds coming from the valve cover area.