- Worn pushrod tubes: The pushrod tubes guide the pushrods from the camshaft to the rocker arms. If the pushrod tubes are worn, they can allow the pushrods to move around excessively, which can cause the rocker arms to come out of adjustment.
- Worn rocker arm shafts: The rocker arm shafts are the shafts that the rocker arms pivot on. If the rocker arm shafts are worn, they can allow the rocker arms to move around excessively, which can cause them to come out of adjustment.
- Worn rocker arms: The rocker arms themselves can also become worn, which can cause them to come out of adjustment.
- Incorrectly adjusted valve clearances: If the valve clearances are not correctly adjusted, it can cause the rocker arms to come out of adjustment.
If you have checked the adjustment screw and nut and they are fine, you should inspect the pushrod tubes, rocker arm shafts, and rocker arms for wear. If any of these components are worn, they should be replaced. You should also check the valve clearances and adjust them if necessary.
Here are some additional tips for troubleshooting a rocker arm that keeps going out of adjustment:
- Make sure that the engine is running at the correct idle speed. If the engine is idling too slowly, it can cause the rocker arms to come out of adjustment.
- Check the engine oil level and condition. If the engine oil is low or dirty, it can cause the rocker arms to come out of adjustment.
- Make sure that the fuel mixture is correct. If the fuel mixture is too lean, it can cause the engine to run hot, which can lead to the rocker arms coming out of adjustment.
If you have followed all of these steps and the rocker arm still keeps going out of adjustment, you may need to take the engine to a qualified mechanic for further diagnosis and repair.
