Replace Your Worn Rocker Arm Shaft in 10 Easy Steps
Rocker arm shafts have one function, and that is to hold the rocker arm in place with enough strength to open the valves. Shafts in good condition ensure smooth movements and less friction. That's why damaged rocker arm shafts must be replaced in order to avoid more friction that can significantly reduce your vehicle’s mileage. Not only will a broken rocker arm shaft affect the mileage, it will also give a loud noise when the engine is turned on. When you experience a loud noise from your engine, make sure to check the shafts too and replace them immediately.
Difficulty level: Moderate
Things you’ll need:
•Clean fuel oil
•New rocker arm shafts
Step 1: Make sure that the negative battery cable is disconnected, then clean the dirt and grime off the valve rocker cover before removing it.
Step 2: Disconnect the fuel pipes. Before removing them, however, make sure to cover right away the injector fuel inlet and outlet openings with caps. This should keep these components free of dirt and other foreign particles.
Step 3: Align the rocker arms and the injector horizontally by cranking the engine using a starting motor. Turning the crankshaft is an alternative method for this step. When using a wrench and barring tool, bar the crankshaft in a right-hand direction. Going the opposite will loosen the crankshaft bolt.
Step 4: The rocker arm shaft is connected to the cylinder head by the rocker arm shaft brackets. Loosen the bolts that secure the brackets in place in order to remove the shaft.
Step 5: Before taking out the shaft, make sure to fold the rocker arms to give room for the shaft. It is also important not to force the arms when folding them back while the shaft is still connected. Doing this may damage other components like the push rods.
Step 6: To completely assess the problem that causes the loud noise from your engine, remove the rocker arms as well. Loosen all the necessary nuts attached to the push rods and clevises before unscrewing the arms from the rods.
Step 7: Get rid of dirt, grime, and other foreign particles found on your rocker arm shaft, as well as the bolts and brackets for it. Use a clean fuel oil.
Step 8: Ensure that the rocker arms and shaft bolts are thoroughly cleaned and dried to effectively spot signs of wear. Using a small wire is necessary when cleaning small passages while a can of compressed air is advised to dry these parts.
Step 9: Carefully inspect the rocker arm shaft for damages.
Step 10: Measure the rocker arm shaft diameter and compare it with the rocker arm diameter to get the oil clearance. Keep in mind that the oil clearance must not exceed 0.004 inches and the allowable clearance is from 0.0006 inches to 0.0024 inches.
The entire process of removing the rocker arm shaft should take experienced DIYers about 30 minutes more or less.