Crankshaft Main Bearing

TORQUE SPECIFICATIONS






CRANKSHAFT JOURNAL DIAMETER AND LIMITS

Limits of taper or out-of-round on any crankshaft journals should be held to 0.005 mm (0.0001 in.).

CRANKSHAFT TORQUE







MAIN BEARING SIZE CODES














1. Clean crankshaft bearing points in crankcase, crankshaft bearing caps and crankshaft journal for crankshaft using a chamois leather.
2. After bearing damage has occurred, it may be necessary to remove debris from the connecting rod bores and from the crankshaft and crankcase oil galleries as well as from the crankcase.
a. Do not use a hard object for cleaning.
b. Blow through oil galleries in direction of flow oil with compressed air.




3. The top main bearing halves are assigned to the crankshaft journal by means of a colored coding (on the rear of the main bearing shells) and numbers or chisel punches, which are stamped on the crankcase.

NOTE: Only assigned color and numerical combinations (see table) may be fitted together.





4. The bottom crankshaft bearing shells are assigned to the crankshaft journal of the crankshaft by means of letters (initial letter of the particular color). The colored coding of the lower crankshaft journal is located at its rear. The initial letters of the particular colors are engraved on the crankshaft journal.

NOTE: When installing the crankshaft bearing shells it is important to keep to the order of the colors which is engraved on the crankshaft journal.





5. Arrow identifies direction of travel:
a. First letter r: A crankshaft bearing shell must be inserted in the crankshaft bearing cap with the colored coding red.
b. Second letter b: A crankshaft bearing shell must be inserted in the crankshaft bearing cap with the colored coding blue.
c. Third letter v: A crankshaft bearing shell must be inserted in the crankshaft bearing cap with the colored coding violet.
d. Fourth letter w: A crankshaft bearing shell must be inserted in the crankshaft bearing cap with the colored coding white.