Crankshaft/Connecting Rod Bearing - Selection
BULLETIN NUMBER ISSUE DATE GROUPSB86-01-003 July 18, 1986 ENGINE
MODELS AFFECTED
1986 Impulse (JR) Turbo models (4ZC1 engine).
SERVICE INFORMATION
Crankshaft main and connecting rod bearing inserts are available in varying thicknesses. This Service
Bulletin contains an explanation of the bearing insert color coding and the size markings on the engine block, crankshaft and connecting rods.
SERVICE PROCEDURE
CRANKSHAFT:
CRANKSHAFT BEARING SELECTION
When installing new crankshaft bearings or replacing old bearings, refer to the selection table below.
CRANKSHAFT:
Crankshaft bearing
Select and install the new connecting rod bearings, paying close attention to the cylinder body journal hole diameter size mark (1) and the crankshaft journal diameter size mark (2).
mm (in.)
(1) Cylinder Body Crankshaft Journal Crankshaft Bearing Oil Clearance
Size Mark Journal Diameter Size Mark (Reference)
(2) Size mark Diameter (Upper & Lower)
- 55.928-55.935 Blue 0.025-0.050
1 59.990-60.000 (2.2035-2.2038) (0.0010-0.0019)
(2.3636-2.3640)
- - 55.920-55.927 0.025-0.050
(2.2032-2.2035)
Black (0.0010-0.0019)
- 55.928-55.935 0.023-0.047
2 59.980-59.989 (2.2035-2.2038) (0.0009-0.0018)
(2.3632-2.3635)
- - 55.920-55.927 0.023 -0.047
(2.2032 -2.2035) Brown (0.0009-0.0018)
Under size 55.670-55.685
0.25 59.980-60.000 (2.1934-2.1940)
0.025-0.084
(2.3632-2.3640) Stamp of size (0.0010-0.0033)
Under size 55.420-55.435
0.50 (2.1835-2.1841)
CONNECTING ROD:
Connecting rod bearing selection
Select and install the now connecting rod bearings, paying close attention to the connecting rod big end diameter size mark.
Note: Take care not to confuse the alignment mark and the size mark during the installation procedure.
(1) Big end Bore Crankshaft Connecting Rod Color of Oil Clearance
Size Mark Diameter Pin Diameter Bearing Thickness Size Mark
A 51.996-52.000 1.513-1.517 Blue 0.022-0.049
- (2.0486-2.0488) (0.0596-0.0597) (0.0009-0.0019)
B 51.988-51.995 1.509-1.513 Black 0.022-0.052
(2.0483-2.0486) (0.0594-0.0596) (0.0009-0.0020)
C 51.983-51.987 1.505-1.509 Brown 0.025-0.052
(2.0481-2.0482) 48.925-48.940 (0.0592-0.0594) (0.0010-0.0020)
Under Size (1.9276-1.9282) 1.623-1.635
0.25 51.983-52.000 (0.0639-0.0644)
Stamp of 0.025-0.079
Under Size (2.0481-2.0482) 1.748-1.760 Size Mark (0.0010-0.0031)
0.50 (0.0688-0.0693)