LINK GP-STEERING 3369370 - Caterpillar

Do not damage contact surfaces when marks are put on lifters.
When a new camshaft is installed, use new lifters. When a lifter has worn to fit the cam of one shaft, do not install it to run against the cam of a new or different camshaft. New lifters can be installed with a used camshaft if necessary.
In addition to correct installation of lifters, they must have good lubrication when the engine is first started. During engine assembly, be sure to put enough engine oil on the lifter assemblies, the cams of the camshaft, and all bearing surfaces to give the necessary lubrication. This will prevent damage to friction surfaces at the time the engine is started, before oil can flow through the system.
These rules, when carefully followed, will extend the service life of camshafts and valve lifters for maximum engine performance.