D 350 Pickup L6-359 59L DSL (1989) - Cylinder Block Assembly Specifications
Crankshaft Main Bearing: Testing and Inspection
CRANKSHAFT AND MAIN BEARINGS
Improper maintenance of the lubrication system is the primary cause of reduced main bearing life.
A malfunction of the crankshaft main bearing will usually be detected by reduced oil pressure. As with rod bearings, continued operation with low
oil pressure will lead to a rapid deterioration of the bearings and eventually will produce a knocking sound.
An excessively worn main bearing will be heard when the engine is loaded.
A damaged or worn thrust bearing flange of the upper main bearing shell can be detected by measuring the end play of the crankshaft.