2. Excessive "blueing" or "coking" of oil along the
complete length of the shaft (A) indicates a possible
lack of lubrication caused by an engine failure, or
improper operation, such as hot shutdowns.
Checking for Oil "Coking" on Shaft
TURBOCHARGER BENCH TEST
1. Mount the turbocharger in a vise.
2. Rotate the shaft, using both hands, to check rotation
and clearance. The shaft should turn freely, however,
there may be a slight amount of drag.
Checking Shaft Rotation and Clearance
Continued on next page