Part 1

CYLINDER BLOCK


Inspection


CRANKSHAFT END PLAY





- Measure the clearance between thrust bearings and crankshaft arm when crankshaft is moved fully forward or backward with a dial indicator.

Standard and limit : Refer to EM-143, "Cylinder Block". Specifications

- If the measured value exceeds the limit, replace thrust bearings, and measure again. If it still exceeds the limit, replace crankshaft also.

CONNECTING ROD SIDE CLEARANCE





- Measure the side clearance between connecting rod and crankshaft arm with a feeler gauge.

Standard and limit : Refer to EM-143, "Cylinder Block". Specifications

- If the measured value exceeds the limit, replace connecting rod, and measure again. If it still exceeds the limit, replace crankshaft also.

PISTON TO PISTON PIN OIL CLEARANCE

Piston Pin Hole Diameter





Measure the inner diameter of piston pin hole with an inside micrometer (A).

Standard : Refer to EM-143, "Cylinder Block". Specifications


Piston Pin Outer Diameter





Measure the outer diameter of piston pin with a micrometer (A).

Standard : Refer to EM-143, "Cylinder Block". Specifications


Piston to Piston Pin Oil Clearance
(Piston to piston pin oil clearance) = (Piston pin hole diameter) � (Piston pin outer diameter)

Standard : Refer to EM-143, "Cylinder Block". Specifications

- If the calculated value is out of the standard, replace piston and piston pin assembly.
- When replacing piston and piston pin assembly, Description.

NOTE:
- Piston is available together with piston pin as assembly.
- Piston pin (piston pin hole) grade is provided only for the parts installed at the plant. For service parts, no piston pin grades can be selected. (Only "0" grade is available.)

PISTON RING SIDE CLEARANCE





- Measure the side clearance of piston ring (1) and piston ring groove with a feeler gauge (C).

A : NG
B : OK

Standard and limit : Refer to EM-143, "Cylinder Block". Specifications

- If the measured value exceeds the limit, replace piston ring, and measure again. If it still exceeds the limit, replace piston also.

PISTON RING END GAP
- Check that the cylinder bore inner diameter is within the specification. Disassembly and Assembly.





- Lubricate with new engine oil to piston (1) and piston ring (2), and then insert piston ring until middle of cylinder with piston, and measure the piston ring end gap with a feeler gauge (B).

A : Press-fit
C : Measuring point

Standard and limit : Refer to EM-143, "Cylinder Block". Specifications

- If the measured value exceeds the limit, replace piston ring, and measure again. If it still exceeds the limit, rebore cylinder and use oversize piston and piston rings.

CONNECTING ROD BEND AND TORSION





- Check with a connecting rod aligner.

A : Bend
B : Torsion
C : Feeler gauge

Bend limit
Torsion limit: Refer to EM-143, "Cylinder Block". Specifications

- If it exceeds the limit, replace connecting rod assembly.

CONNECTING ROD BIG END DIAMETER





- Install connecting rod bearing cap without installing connecting rod bearing, and tighten connecting rod bolts to the specified torque. Disassembly and Assembly for the tightening procedure.

1 : Connecting rod

- Measure the inner diameter of connecting rod big end with an inside micrometer.

Standard : Refer to EM-143, "Cylinder Block". Specifications

- If out of the standard, replace connecting rod assembly.

CONNECTING ROD BUSHING OIL CLEARANCE

Connecting Rod Bushing Inner Diameter





Measure the inner diameter of connecting rod bushing with an inside micrometer (A).

Standard : Refer to EM-143, "Cylinder Block". Specifications

Piston Pin Outer Diameter





Measure the outer diameter of piston pin with a micrometer (A).

Standard : Refer to EM-143, "Cylinder Block". Specifications

Connecting Rod Bushing Oil Clearance
(Connecting rod bushing oil clearance) = (Connecting rod bushing inner diameter) � (Piston pin outer diameter)

Standard and limit : Refer to EM-143, "Cylinder Block". Specifications

- If the calculated value exceeds the limit, replace connecting rod assembly and/or piston and piston pin assembly.
- If replacing piston and piston pin assembly, Description.





- If replacing connecting rod assembly, refer to EM-133 "Connecting Rod Bearing" to select the connecting rod bearing.

A : Sample codes
B : Bearing stopper groove
C : Small-end diameter grade
D : Big-end diameter grade
E : Weight grade
F : Cylinder No.
G : Management code
H : Front mark
I : Management code

Factory installed parts grading:





- Service parts apply only to grade "0".

A : RH
B : LH
C : Piston pin grade number
D : Piston grade number
E : Front mark
F : Identification code





CYLINDER BLOCK DISTORTION
- Using a scraper, remove gasket on the cylinder block surface, and also remove engine oil, scale, carbon, or other contamination.

CAUTION:
Be careful not to allow gasket flakes to enter engine oil or engine coolant passages.





- Measure the distortion on the cylinder block upper face at some different points in six directions (C), (D), (E), (F), (G), and (H) with a straightedge (A) and a feeler gauge (B).

Limit : Refer to EM-143, "Cylinder Block". Specifications

- If it exceeds the limit, replace cylinder block.

MAIN BEARING HOUSING INNER DIAMETER





- Install lower cylinder block (2) without installing main bearings, and tighten lower cylinder block bolts to the specified torque. Disassembly and Assembly for the tightening procedure.
- Measure the inner diameter of main bearing housing with a bore gauge.

Standard : Refer to EM-143, "Cylinder Block". Specifications

- If out of the standard, replace cylinder block (1) and lower cylinder block as assembly.

NOTE:
Cylinder block cannot be replaced as a single part, because it is machined together with lower cylinder block.

PISTON TO CYLINDER BORE CLEARANCE

Cylinder Bore inner Diameter





- Using a bore gauge, measure cylinder bore for wear, out-of-round and taper at six different points on each cylinder. [(A) and (B) directions at (C), (D) and (E)] is in longitudinal direction of engine.

f : 10 mm (0.39 in)
g : 60 mm (2.36 in)
h : 125 mm (4.92 in)
Standard and limit : Refer to EM-143, "Cylinder Block". Specifications





- If the measured value exceeds the limit, or if there are scratches and/or seizure on the cylinder inner wall, hone or rebore the inner wall.
- Oversize piston is provided. When using oversize piston, rebore cylinder so that the clearance of the piston-to-cylinder bore satisfies the standard.

CAUTION:
When using oversize piston, use oversize pistons for all cylinders with oversize piston rings.

Oversize (O/S) : 0.2 mm (0.008 in)

Piston Skirt Diameter





Measure the outer diameter of piston skirt with a micrometer (A).

Measure point
Standard: Refer to EM-143, "Cylinder Block". Specifications

Piston-to-Cylinder Bore Clearance





Calculate by piston skirt diameter and cylinder bore inner diameter
[direction (B), position (D)].

A : Direction A
C : Position C
E : Position E
f : 10 mm (0.39 in)
g : 60 mm (2.36 in)
h : 125 mm (4.92 in)

(Clearance) = (Cylinder bore inner diameter) � (Piston skirt diameter).

Standard and limit : Refer to EM-143, "Cylinder Block". Specifications

- If the calculated value exceeds the limit, replace piston and piston pin assembly. Specifications.

Reboring Cylinder Bore
1. Cylinder bore size is determined by adding piston to cylinder bore clearance to piston skirt diameter.

Rebored size calculation: D = A + B - C where,
A: Piston skirt diameter as measured
B: Piston to cylinder bore clearance (standard value)
C: Honing allowance 0.02 mm (0.0008 in)
D: Bored diameter

2. Install lower cylinder block, and tighten to the specified torque. Otherwise, cylinder bores may be distorted in final assembly.
3. Cut cylinder bores.

NOTE:
- When any cylinder needs boring, all other cylinders must also be bored.
- Do not cut too much out of cylinder bore at a time. Cut only 0.05 mm (0.0020 in) or so in diameter at a time.
4. Hone cylinders to obtain the specified piston to cylinder bore clearance.
5. Measure finished cylinder bore for the out-of-round and taper.

NOTE:
Perform measurement after cylinder bore cools down.

CRANKSHAFT MAIN JOURNAL DIAMETER
- Measure the outer diameter of crankshaft main journals with a micrometer.

Standard : Refer to EM-143, "Cylinder Block". Specifications

- If out of the standard, measure the main bearing oil clearance. Then use undersize bearing. Service and Repair.

CRANKSHAFT PIN JOURNAL DIAMETER





- Measure the outer diameter of crankshaft pin journal with a micrometer (A).

Standard : Refer to EM-143, "Cylinder Block". Specifications

- If out of the standard, measure the connecting rod bearing oil clearance. Then use undersize bearing. Connecting Rod Bearing.

CRANKSHAFT OUT-OF-ROUND AND TAPER





- Measure the dimensions at four different points as shown in the figure on each main journal and pin journal with a micrometer.
- Out-of-round is indicated by the difference in the dimensions between (d) and (c) at (a) and (b).
- Taper is indicated by the difference in the dimensions between.

Limit : Refer to EM-143, "Cylinder Block". Specifications

- If the measured value exceeds the limit, correct or replace crankshaft.
- If corrected, measure the bearing oil clearance of the corrected main journal and/or pin journal. Then select the main bearing and/
or connecting rod bearing. Service and Repair and/or Connecting Rod Bearing.

CRANKSHAFT RUNOUT





- Place V-block on precise flat table, and support the journals on both ends of crankshaft.
- Place a dial indicator straight up on the No. 3 journal.
- While rotating crankshaft, read the movement of the pointer on a dial indicator. (Total indicator reading)

Standard and limit : Refer to EM-143, "Cylinder Block". Specifications

- If it exceeds the limit, replace crankshaft.