Crankshaft And Crankshaft Bearing

Clean the crankshaft completely, and check it for cracks using liquid penetrant tester. Replace if faulty.
Measure the bend of crankshaft. If it exceeds the limit, correct or replace it.
NOTE: If a suitable V-block is not available, install #1 and #5 crankshaft bearing on cylinder block, position the crankshaft on these bearings, and then measure the crankshaft bend using a dial gauge.

Crankshaft bend limit: 0.035 mm (0.0014 in)

Fig 1: Measuring Crankshaft
Courtesy of SUBARU OF AMERICA, INC.

Inspect the crank journal and crank pin for wear. If they are not within the standard, replace the bearing with a suitable (undersize) one, and replace or readjust crankshaft as necessary. When grinding the crank journal or crank pin, finish them to the specified dimensions according to the undersize bearing to be used.

Crank pin

Out-of-roundness: 0.003 mm (0.0001 in)

Cylindricality: 0.004 mm (0.0002 in)

Grinding limit: To 51.750 mm (2.0374 in) dia.

Crank journal

Out-of-roundness: 0.005 mm (0.0002 in)

Cylindricality: 0.006 mm (0.0002 in)

Grinding limit: To 59.758 mm (2.3527 in) dia.

Fig 2: Inspecting Crank Journal And Crank Pin

Courtesy of SUBARU OF AMERICA, INC.

CRANK JOURNAL OUTER DIAMETER SPECIFICATION

Unit: mm (in)
		Crank journal outer diameter		Crank pin outer diameter
		#1, #3	#2, #4, #5	Crank pin outer diameter
Standard	Journal O.D.	59.992 - 60.008 (2.3619 - 2.3625)	59.992 - 60.008 (2.3619 - 2.3625)	51.984 - 52.000 (2.0466 - 2.0472)
Standard	Bearing size (Thickness at center)	1.998 - 2.011 (0.0787 - 0.0792)	2.000 - 2.013 (0.0787 - 0.0793)	1.492 - 1.501 (0.0587 - 0.0591)
0.03 (0.0012) Undersize	Journal O.D.	59.962 - 59.978 (2.3607 - 2.3613)	59.962 - 59.978 (2.3607 - 2.3613)	51.954 - 51.970 (2.0454 - 2.0461)
0.03 (0.0012) Undersize	Bearing size (Thickness at center)	2.017 - 2.020 (0.0794 - 0.0795)	2.019 - 2.022 (0.0795 - 0.0796)	1.510 - 1.513 (0.0594 - 0.0596)
0.05 (0.0020) Undersize	Journal O.D.	59.942 - 59.958 (2.3599 - 2.3605)	59.942 - 59.958 (2.3599 - 2.3605)	51.934 - 51.950 (2.0446 - 2.0453)
0.05 (0.0020) Undersize	Bearing size (Thickness at center)	2.027 - 2.030 (0.0798 - 0.0799)	2.029 - 2.032 (0.0799 - 0.0800)	1.520 - 1.523 (0.0598 - 0.0600)
0.25 (0.0098) Undersize	Journal O.D.	59.742 - 59.758 (2.3520 - 2.3527)	59.742 - 59.758 (2.3520 - 2.3527)	51.734 - 51.750 (2.0368 - 2.0374)
0.25 (0.0098) Undersize	Bearing size (Thickness at center)	2.127 - 2.130 (0.0837 - 0.0839)	2.129 - 2.132 (0.0838 - 0.0839)	1.620 - 1.623 (0.0638 - 0.0639)

Measure the thrust clearance of crankshaft at center bearing by using thickness gauge. If the thrust clearance is not within the standard, replace the bearing.
Crankshaft thrust clearance:

Standard: 0.030 - 0.115 mm (0.0012 - 0.0045 in)

Fig 3: Checking Crankshaft Thrust Clearance
Courtesy of SUBARU OF AMERICA, INC.
Inspect individual crankshaft bearings for signs of flaking, seizure, melting and wear.
Measure the oil clearance on each crankshaft bearing using plastigauge. If the measured value is out of standard, replace the defective bearing with an undersize one, and replace or grind to correct the crankshaft as necessary.
Crankshaft oil clearance:

Standard: 0.010 - 0.030 mm (0.0004 - 0.0012 in)