Connecting Rod Bearing
CONNECTING ROD BEARING HOUSING DIAMETER (BIG END)
^ Install the connecting rod cap without the connecting rod bearing installed. After tightening the connecting rod nut to the specified torque, measure the connecting rod bearing housing big end inner diameter using an inside micrometer.
Standard: 55.000 - 55.013 mm (2.1654 - 2.1659 inch)
CONNECTING ROD BUSHING OIL CLEARANCE (SMALL END)
Inner Diameter of Connecting Rod (Small End)
^ Measure inner diameter of piston pin bushing.
Standard
Grade No. 0: 22.000 - 22.006 mm (0.8661 - 0.8664 inch)
Grade No. 1: 22.006 - 22.012 mm (0.8664 - 0.8666 inch)
Outer Diameter of Piston Pin
^ Measure outer diameter of piston pin.
Standard
Grade No. 0: 21.989 - 21.995 mm (0.8657 - 0.8659 inch)
Grade No. 1: 21.995 - 22.001 mm (0.8659 - 0.8662 inch)
Connecting Rod Bushing Oil Clearance (Small End)
(Connecting rod small end oil clearance) = (Inner diameter of connecting rod small end) (Outer diameter of piston pin)
Standard: 0.005 - 0.017 mm (0.0002 - 0.007 inch)
Limit: 0.030 - mm (0.0012 inch)
^ If the measured value exceeds the standard, replace the connecting rod assembly and/or piston and piston pin assembly.
^ If replacing the piston and piston pin assembly, refer to the Table for Selective Fitting for Piston to select the piston corresponding to the applicable bore grade of the cylinder block to be used.
Factory installed parts grading:
^ Service parts apply only to grade 0.
BEARING CLEARANCE
^ Use either of the following two methods, however method A gives more reliable results and so is the preferred method.
Method A (Using Bore Gauge and Micrometer)
Main Bearing
1. Set the main bearings in their proper positions on the cylinder block and the main bearing cap.
2. Install the main bearing caps and bearing beam to the cylinder block. Tighten all bolts in the numerical order as specified.
3. Measure the inner diameters A of each main bearing as shown.
4. Measure the outer diameters Dm of each crankshaft main journal as shown.
5. Calculate the main bearing clearance.
Main bearing clearance = A - Dm
Standard: 0.035 - 0.045 mm (0.0014 - 0.0018 inch)
Limit: 0.065 mm (0.0026 inch)
^ If it exceeds the limit, replace the bearing.
^ If clearance cannot be adjusted using any standard bearing grade, grind crankshaft journal and use an undersized bearing.
^ When grinding the crankshaft journal, confirm that the L dimension in the fillet role is more than the specified limit.
L: 0.1 mm (0.004 inch)
6. If the crankshaft or the cylinder block is replaced with a new one, select thickness of the main bearings as follows:
a. The grade number of each cylinder block main journal is punched on the respective cylinder block. These numbers are punched in either Arabic or Roman numerals. If measured diameter is out of the grade punched, decide suitable grade from available main bearings.
b. The grade number of each crankshaft main journal is punched on the crankshaft end. These numbers are punched in either Arabic or Roman numerals. If measured diameter is out of grade punched, decide the suitable grade from available main bearings.
c. Select the main bearing suitable thickness according to the following table:
Connecting Rod Bearing (Big End)
1. Install the connecting rod bearing to the connecting rod and cap.
2. Install the connecting rod cap to the connecting rod. Tighten to specification.
3. Measure the inner diameter C of each connecting rod (big end) as shown.
4. Measure the outer diameter Dp of each crankshaft pin journal.
5. Calculate the connecting rod bearing clearance.
Connecting rod bearing clearance = C - Dp
Standard: 0.034 - 0.059 mm (0.0013 - 0.0023 inch)
Limit: 0.070 mm (0.0028 inch)
6. If the calculated clearance exceeds the specified limit, replace the bearings.
7. If the clearance cannot be adjusted within the standard of any bearing, grind the crankshaft journal and use undersized bearings.
8. If the crankshaft is replaced with a new one, select the connecting rod bearings according to the following table:
Connecting Rod Bearing Grade Number (Identification Color)
These numbers are punched in either Arabic or Roman numerals.
Method B (Using Plastigage)
^ Remove oil and dust on the crankshaft pin and the surfaces of each bearing completely.
^ Cut a Plastigage slightly shorter than the bearing width, and place it in crankshaft axial direction, avoiding oil holes.
^ Install the connecting rod bearings to the connecting rod cap, and tighten the connecting rod nuts to the specified torque.
CAUTION: Never rotate the crankshaft.
^ Remove the connecting rod cap and bearings, and using the scale on the Plastigage bag, measure the Plastigage width.
NOTE: The procedure when the measured value exceeds the repair limit is same as that described in Method A (Using Bore Gauge and Micrometer).
CONNECTING ROD BEARING:
CONNECTING ROD BEARING
Undersize:
Undersize
BEARING CLEARANCE:
BEARING CLEARANCE