Valve springs can be visually inspected for tension and broken valve stems with seals can be serviced without removal of the cylinder head usually requiring a technician and two specialized tools and compressed air. In emergency when compressed air is not available, a nylon rope can be used so as to stop the valves from falling into the cylinder. To be started by using the removal of
Rocker Arm cover and the spark plug from the cylinder in consideration, or all spark plugs if all the valve stem seals will be replaced. Make the piston at the top dead center of the compression strokes while making the necessary adjustment on the valves, and the adjustment can be done one cylinder after another starting at the firing order sequence. Slip an adapter into the spark plug hole and attach an air hose to a can of compressed air. Take out the bolt, pivot ball and the rocker arm for the bad valve and pull out the
Pushrod. Use compressed air to retain the valve; if there is leakage, another way is to sit the piston at a little before TDC and then put nice nylon rope in the combustion chamber. The parts next need to be protected from falling into the engine, which can be done by using shop rags, then you use a valve spring compressor to remove the keepers and compress the valve spring. Remove the valve stem O-ring seal and the spring retainer shield and examine the valve spring if it is damaged or not. It is wise to cover the valve stem with a rubber band or tape so that it does not fall, and let out the air pressure. Check the valve stem for signs of wear and tear and make sure the same spins freely in the guide. Reapply air pressure to hold the valve in place, oil the valve stem with the engine oil, and in case replace the umbrella type guide seal if at all needed. Mount the spring over the valve and the shield and fit the retainer of the valve spring into its seat to accommodate the new and finer O-ring seal. Place the keepers in the upper groove and use grease for the same if the groove is not able to hold the keepers in place. Pull off all the pressure from the spring tool, detach the hose from the air and take off the adapter from the spark plug hole. Put in the rocker arm(s) and the pushrod(s) and the spark plug(s) together with the wire and put back the rocker arm cover. Take the handles and start the engine checking the area of the rocker arm cover for any signs of oil leakage or any unusual sounds.