BRACKET AS 7W7078 - Caterpillar

Probable Causes
Incorrect bridge and/or valve lash
Insufficient lubrication
Problem in the cylinder head and/or related components
Problem with the bolts for the precombustion chamberRecommended Actions
Valve Bridge and Valve Lash
Check the valve bridge and valve lash according to Systems Operation/Testing and Adjusting, "Engine Timing Procedures".Insufficient Lubrication
Inspect the valve train for sufficient lubrication. The passages for the engine oil must be clean.Cylinder Head and Related Components
Measure the cylinder compression. Refer to the engine's Operation and Maintenance Manual, "Cylinder Pressure - Measure/Record".Inspect the components of the valve train: valves, valve springs, locks and valve rotators.Inspect the contact surfaces of the rocker arm and valve bridge.Inspect the pushrods.Check for free movement of the valves. If the valves do not move freely, look for these conditions:
A valve stem is bent.
The camshaft lifters are damaged or the lifters are worn.
The camshaft is damaged or the camshaft is worn.
A retaining bolt for a rocker shaft is loose or the bolt is broken.Replace components that are worn and/or damaged.If a camshaft is replaced, new valve lifters must be installed.Bolts for the Precombustion Chamber
Inspect the bolts for the precombustion chamber. Make sure that the bolts are not loose or broken. Replace the bolts, if necessary.