Crankshaft: Service and Repair
CYLINDER BLOCK
How to Select Piston and Bearing
DESCRIPTION
- The identification grade stamped on each part is the grade for the dimension measured in new condition.
This grade cannot apply to reused parts.
- For reused or repaired parts, measure the dimension accurately. Determine the grade by comparing the measurement with the values of each selection table.
- For details of the measurement method of each part, the reuse standards and the selection method of the selective fitting parts, use the applicable procedures.
HOW TO SELECT PISTON
When New Cylinder Block is Used
- Check the cylinder bore grade on rear left side of cylinder block (L), and select piston of the same grade.
A : Correction stamp
B : Standard stamp
C : Cylinder No. 1 bore grade
D : Cylinder No. 2 bore grade
E : Cylinder No. 3 bore grade
F : Cylinder No. 4 bore grade
G : No. 1 main bearing housing grade
H : No. 2 main bearing housing grade
I : No. 3 main bearing housing grade
J : No. 4 main bearing housing grade
K : No. 5 main bearing housing grade
White Arrow Indicates Engine front
- If there is a correction stamp mark on the cylinder block, use it as a correct reference.
When Cylinder Block is Reused
1. Measure the cylinder bore inner diameter. Refer to Inspection.
2. Determine the bore grade by comparing the measurement with the values under the cylinder bore inner diameter of the "Piston Selection Table".
3. Select piston of the same grade.
A : Identification code
B : Front mark
C : Piston grade number
D : Pin grade number
Piston Selection Table
NOTE:
- Piston is available together with piston pin as an assembly.
- There is no piston pin (piston pin hole) grade.
HOW TO SELECT CONNECTING ROD BEARING
When New Connecting Rod and Crankshaft are Used
1. Apply connecting rod big end diameter grade stamped (C) on connecting rod side face to the row in the "Connecting Rod Bearing Selection Table".
A : Oil hole
B : Cylinder number
D : Small end diameter grade
E : Front mark
2. Apply crankshaft pin journal diameter grade stamped on crankshaft front side to the column in the "Connecting Rod Bearing Selection Table".
A : No. 1 pin journal diameter grade
B : No. 2 pin journal diameter grade
C : No. 3 pin journal diameter grade
D : No. 4 pin journal diameter grade
E : No. 1 main journal diameter grade
F : No. 2 main journal diameter grade
G : No. 3 main journal diameter grade
H : No. 4 main journal diameter grade
I : No. 5 main journal diameter grade
3. Read the symbol at the cross point of selected row and column in the "Connecting Rod Bearing Selection Table".
4. Apply the symbol obtained to the "Connecting Rod Bearing Grade Table" to select connecting rod bearing.
When Crankshaft and Connecting Rod are Reused
1. Measure the dimensions of the connecting rod big end diameter and crankshaft pin journal diameter individually. Refer to Inspection and Inspection.
2. Apply the measured dimension to the "Connecting Rod Bearing Selection Table".
3. Read the symbol at the cross point of selected row and column in the "Connecting Rod Bearing Selection Table".
4. Apply the symbol obtained to the "Connecting Rod Bearing Grade Table" to select connecting rod bearing.
Connecting Rod Bearing Selection Table
Connecting Rod Bearing Grade Table
Undersize Bearings Usage Guide
- When the specified connecting rod bearing oil clearance is not obtained with standard size connecting rod bearings, use undersize (US) bearings.
- When using undersize (US) bearing, measure the connecting rod bearing inner diameter with bearing installed, and grind the crankshaft pin so that the connecting rod bearing oil clearance satisfies the standard.
CAUTION:
In grinding crankshaft pin to use undersize bearings, keep the fillet R [1.5 - 1.7 mm (0.059 - 0.067 in)] (A).
HOW TO SELECT MAIN BEARING
When New Cylinder Block and Crankshaft are Used
1. "Main Bearing Selection Table" rows correspond to main bearing housing grade on rear left side of cylinder block (L).
A : Correction stamp
B : Standard stamp
C : Cylinder No. 1 bore grade
D : Cylinder No. 2 bore grade
E : Cylinder No. 3 bore grade
F : Cylinder No. 4 bore grade
G : No. 1 main bearing housing grade
H : No. 2 main bearing housing grade
I : No. 3 main bearing housing grade
J : No. 4 main bearing housing grade
K : No. 5 main bearing housing grade
White Arrow Indicates Engine front
- If there is a correction stamp mark on cylinder block, use it as a correct reference.
2. Apply main journal diameter grade stamped on crankshaft front side to column in the "Main Bearing Selection Table".
A : No. 1 pin journal diameter grade
B : No. 2 pin journal diameter grade
C : No. 3 pin journal diameter grade
D : No. 4 pin journal diameter grade
E : No. 1 main journal diameter grade
F : No. 2 main journal diameter grade
G : No. 3 main journal diameter grade
H : No. 4 main journal diameter grade
I : No. 5 main journal diameter grade
3. Read the symbol at the cross point of selected row and column in the "Main Bearing Selection Table".
CAUTION:
There are two main bearing selection tables. One is for No. 1, 4 and 5 journals and the other is for No. 2 and 3 journals. Make certain to use the appropriate table. This is due to differences in the specified clearances.
4. Apply the symbol obtained to the "Main Bearing Grade Table" to select main bearing.
NOTE:
Service part is available as a set of both upper and lower.
When Cylinder Block and Crankshaft are Reused
1. Measure the dimensions of the cylinder block main bearing housing inner diameter and crankshaft main journal diameter individually. Refer to Inspection and Inspection.
2. Apply the measured dimension to the "Main Bearing Selection Table".
3. Read the symbol at the cross point of selected row and column in the "Main Bearing Selection Table".
CAUTION:
There are two main bearing selection tables. One is for No. 1, 4 and 5 journals and the other is for
No. 2 and 3 journals. Make certain to use the appropriate table. This is due to differences in the specified clearances.
4. Apply the symbol obtained to the "Main Bearing Grade Table" to select main bearing.
NOTE:
Service part is available as a set of both upper and lower.
Main Bearing Selection Table (No. 1, 4 and 5 journals)
Main Bearing Selection Table (No. 2 and 3 journals)
Main Bearing Grade Table (All Journals)
Use Undersize Bearing Usage Guide
- When the specified main bearing oil clearance is not obtained with standard size main bearings, use undersize (US) bearing.
- When using undersize (US) bearing, measure the main bearing inner diameter with bearing installed, and grind main journal so that the main bearing oil clearance satisfies the standard.
CAUTION:
In grinding crankshaft main journal to use undersize bearings, keep the fillet R [1.5 - 1.7 mm (0.059 - 0.067 in)] (A).
