Inspect the main bearings as follows:

Nut

Capscrew

pulley

Lockwasher

Key

Bearing cap

Gear

Bearing shell

5. k e y

10.

Crankshaft

Figure 3-18. Crankshaft assembly.

(8) Remove the capscrews (6) and lock-

diameter of the main bearing journals is 2.4984-

washers (7), and remove the bearing caps (8) and

2.4994 inches. The specified diameter of the

bearing shells (9). Remove the crankshaft (10).

connecting rod journal is 2.1214-2.1224 inches.

(5) Inspect the main bearings as follows:

b. Cleaning, Inspection and Repair.

(a) Replace any bearing shells that are

(11) Clean ail parts with a cleaning solvent.

scored, c h i p p e d , p i t t e d , o r w o r n b e y o n d t h e

(2) Clean the crankshaft oil passages with a

specified limits. Bright spots on the backs of the

solvent and blow out with compressed air.

shells indicates bearings have shifted in their

(3) inspect the c r a n k s h a f t j o u r n a l s f o r

supports and must be replaced.

scoring. chipping, cracking, or signs of overheating.

(b) Insert a 1 / 32 inch diameter soft lead

if the crankshaft has overheated (usually indicated

wire or a plastic strip manufactured for this pur-

by discolored or blue bearing journal surfaces), or is

scored or excessively worn. recondition or replace

pose across the center of each lower bearing shell by

removing and replacing one bearing cap at a time.

as required. Examine the bearing journals for

crarks if overheating has occured.

Tighten the bearing capscrews to 110 to 120 ft lbs,

(4) Measure the crankshaft main bearing and

crushing the wire or strip to a shim thickness

connecting rod journals at several places on their

between the shells and the crankshaft journals.

diameter to check for roundness. The specified

Remove the bearing caps and measure the

3-21