1D-124 Engine Mechanical: For J20 Engine
Main bearing clearance
Check clearance by using gauging plastic according to
the following procedure.
1) Remove lower crankcase.
2) Clean bearings and main journals.
3) Place a piece of gauging plastic (1) to full width of
bearing (parallel to crankshaft) on journal, avoiding
oil hole.
4) Install lower crankcase to cylinder block referring to
“Main Bearings, Crankshaft and Cylinder Block
Removal and Installation: For J20 Engine”.
NOTE
Do not rotate crankshaft while gauging
plastic is installed.
5) Remove lower crankcase and using scale (2) on
gauging plastic envelop (1), measure gauging plastic
width at its widest point. If clearance exceeds its
limit, replace bearing. Always replace both upper
and lower inserts as a unit.
A new standard bearing may produce proper
clearance. If not, it will be necessary to regrind
crankshaft journal for use of 0.25 mm undersize
bearing.
After selecting new bearing, recheck clearance.
Main Bearing Clearance
Standard: 0.032 – 0.050 mm (0.0013 – 0.0019 in.)
Limit: 0.063 mm (0.0024 in.)
Selection of main bearings
STANDARD BEARING:
If engine is under the following conditions, select a new
standard bearing as followings and install it.
• Bearing is in malcondition.
• Bearing clearance is cut of specification.
• Crankshaft or cylinder block is replaced.
1) First check journal diameter. As shown in figure,
crank web No.2 has stamped numbers.
Six kinds of numbers (“4” through “9”) represent the
following journal diameters.
Journal diameter
Stamped numbers on crank web No.2 (3) represent
journal diameters marked with an arrow in figure
respectively. For example, stamped number “5”
indicates that corresponding journal diameter is
58.0000 – 58.0029 mm (2.28346 – 2.28357 in.).
I2RH01140187-01
I2RH01140188-01
Stamped numbers
Journal diameter
4
58.0030 – 58.0060 mm
(2.28358 – 2.28369 in.)
5
58.0000 – 58.0029 mm
(2.28346 – 2.28357 in.)
6
57.9970 – 57.9999 mm
(2.28334 – 2.28345 in.)
7
57.9940 – 57.9969 mm
(2.28323 – 2.28333 in.)
8
57.9910 – 57.9939 mm
(2.28311 – 2.28322 in.)
9
57.9880 – 57.9909 mm
(2.28299 – 2.28310 in.)
1. Crankshaft pulley side
2. Flywheel side
1
2
3
I4RH01140047-01
www.CarGarage.ir
www.CarGarage.ir
www.CarGarage.ir
