Whenever lifters are installed in a job and the engine is first started, it is recommended that the rocker arm cover be placed in position on cylinder head to prevent oil from being sprayed by the fan. Then run the engine from 1200 to 1500 RPM for 20 minutes or until such time as the lifters assume normal operation. Most jobs will quiet down within a short period of time. If the noise is still prevalent at the end of the 20 minute period, begin to look for trouble as out lined in Section 12.
After all the lifters are filled with oil, close the hood and sit in the driver’s seat. Then vary the throttle opening and listen for valve lifter noise. The engine has an audible valve train noise from approximately 500 to 1200 RPM which may be confused with valve lifter noise if the rocker arm cover is off and the hood is opened. If no valve lifter noise can be heard while sitting in the driver’s seat, the job can be considered satisfactory.
If the noise level appears to be excessively high, remove the rocker arm cover and pour penetrating oil on the valve cap to determine whether or not the noise is caused by a sticky valve. As was explained previously, cocked valve springs, sticking valves, eccentric valve seats, etc. will emit a noise similar to that of a defective valve lifter. If the noise is not eliminated or if the noise level is not changed by the application of penetrating oil, rotate the valve springs. In cases of eccentric valve seating it will be necessary to grind the valves in order to eliminate the noise.
General valve train noise is acceptable as long as it is not annoying while sitting in the driver’s seat with the rocker arm cover on and the hood closed.