Cylinder Block Assembly: Testing and Inspection

CAUTION: When installing sliding parts (bearings, pistons, etc.), lubricate contacting surfaces with new engine oil.
Place removed parts such as bearings and bearing caps in their proper order and direction.
When installing connecting rod nuts and main bearing cap bolts, apply new engine oil to threads and seating surfaces.
Do not allow any magnetic materials to contact the ring gear teeth of flywheel or drive plate.









Inspection
PISTON AND PISTON PIN CLEARANCE
1. Measure inner diameter of piston pin hole "dp".

Standard diameter"dp":.....20.969 - 20.981 mm (0.8255 - 0.8260 inch)






2. Measure outer diameter of piston pin "Dp".

Standard diameter "Dp": .....20.971 - 20.983 mm (0.8256 - 0.8261 inch)

3. Calculate piston pin clearance.

dp - Dp = 0 to (- 0.004) mm [0 to (- 0.0002) inch]

If it exceeds the above value, replace piston assembly with pin.







Inspection
PISTON RING SIDE CLEARANCE

Side clearance:
Top ring: ......0.040 - 0.080 mm (0.0016 - 0.0031 inch)
2nd ring: ......0.030 - 0.070 mm (0.0012 - 0.0028 inch)
Oil ring: ......0.015 - 0.185 mm (0.0006 - 0.0073 inch)

Max. limit of side clearance:
Top ring: .....0.11 mm (0.0043 inch)
2nd ring: ......0.1 mm (0.004 inch)
Oil ring: ......-

If out of specification, replace piston and/or piston ring assembly.







Inspection
PISTON RING END GAP

End gap:
Top ring: .....0.21 - 0.31 mm (0.0083 - 0.0122 inch)
2nd ring: .....0.50 - 0.60 mm (0.0197 - 0.0236 inch)
Oil ring: .....0.20 - 0.60 mm (0.0079 - 0.0236 inch)
Max. limit of ring gap:
Top ring: ......0.43 mm (0.0169 inch)
2nd ring: ......0.69 mm (0.0272 inch)
Oil ring: ......0.84 mm (0.0331 inch)

If out of specification, replace piston ring. If gap still exceeds the limit even with a new ring, rebore cylinder and use oversized piston and piston rings. Refer to Engine; Specifications; Mechanical.

When replacing the piston, check the cylinder block surface for scratches or seizure. If scratches or seizure are found, hone or replace the cylinder block.






Inspection
CONNECTING ROD BEND AND TORSION


Bend:
Limit .....0.15 mm (0.0059 inch) per 100 mm (3.94 inch) length






Torsion:
Limit .....0.30 mm (0.0118 inch) per 100 mm (3.94 inch) length

If it exceeds the limit, replace connecting rod assembly.






Inspection
CYLINDER BLOCK DISTORTION AND WEAR
1. Clean upper face of cylinder block and measure the distortion.

Limit: ......0.10 mm (0.0039 inch)

2. If out of specification, resurface it. The resurfacing limit is determined by cylinder head resurfacing in engine.

Amount of cylinder head resurfacing is "A".
Amount of cylinder block resurfacing is "B".
The maximum limit is as follows: ......A + B = 0.2 mm (0.008 inch)
Nominal cylinder block height from crankshaft center: .....227.60 - 227.70 mm (8.9606 - 8.9645 inch)

3. If necessary, replace cylinder block.







Inspection
PISTON-TO-BORE CLEARANCE
1. Using a bore gauge, measure cylinder bore for wear, out-of-round and taper.

Standard inner diameter: .....91.500 - 91.530 mm (3.6024 - 3.6035 inch)
Wear limit: .....0.20 mm (0.0079 inch)






If it exceeds the limit, rebore all cylinders. Replace cylinder block if necessary.

Out-of-round (X - Y) standard: .....0.015 mm (0.0006 inch)
Taper (A - B or A - C) standard: ......0.015 mm (0.0006 inch)

2. Check for scratches and seizure. If seizure is found, hone it.









If both cylinder block and piston are replaced with new ones, select piston of the same grade number according to the following table. These numbers are punched on cylinder block and piston in either Arabic or Roman numerals.

Combination of Trade number for cylinder bore and Piston:

3. Measure piston skirt diameter.

Piston diameter "A": Refer to Engine; Specification; Mechanical.
Measuring point "a" (Distance from the top): 49.0 mm (1.929 inch)

4. Check that piston-to-bore clearance is within specification.

Piston-to-bore clearance "B":
0.025 - 0.045 mm (0.0010 - 0.0018 inch) for No. 1, 2 and 6 cylinders (and No. 5 cylinder for VG33ER only)
0.015 - 0.025 mm (0.0006 - 0.0010 inch) for No. 3 and 4 cylinders
0.030 - 0.040 mm (0.0012 - 0.0016 inch) for No. 5 cylinder (VG33E only)

5. Determine piston oversize according to amount of cylinder wear. Oversize pistons are available for service. Refer to Engine; Specifications; Mechanical.

6. Cylinder bore size is determined by adding piston-to-bore clearance to piston diameter "A".

Rebored size calculation: D = A + B - C
D:......Bored diameter
A:......Piston diameter as measured
B:......Piston-to-bore clearance
C:......Honing allowance 0.02 mm (0.0008 inch)

7. Install main bearing caps, and tighten to the specified torque to prevent distortion of cylinder bores in final assembly.

8. Cut cylinder bores.
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 inch) or so in diameter at a time.

9. Hone cylinders to obtain specified piston-to-bore clearance.
10. Measure finished cylinder bore for out-of-round and taper.
Measurement should be done after cylinder bore cools down.


Inspection
CRANKSHAFT
1. Check crankshaft main and pin journals for score, wear or cracks.






2. With a micrometer, measure journals for taper and out-of-round.

Out-of-round (X - Y): .....Less than 0.005 mm (0.0002 inch)
Taper (A - B): ......Less than 0.005 mm (0.0002 inch)






3. Measure crankshaft runout.

Runout (Total indicator reading): .....Less than 0.10 mm (0.0039 inch)



NOTE: Either of the following two methods may be used, however, method A gives more reliable results and is preferable.






Inspection
BEARING CLEARANCE
Method A (Using bore gauge & micrometer)

Main Bearing
1. Set main bearings in their proper positions on cylinder block and main bearing cap.
2. Install main bearing cap to cylinder block.
Tighten all bolts in correct order in two or three stages.






3. Measure inner diameter "A" of each main bearing.






4. Measure outer diameter "Dm" of each crankshaft main journal.
5. Calculate main bearing clearance.

No.1 main bearing clearance (A- Dm):
Standard .....0.030 - 0.048 mm (0.0012 - 0.0019in)
Limit ......0.060 mm (0.0024 inch)
No. 2, 3 and No. 4 main bearing clearance (A- Dm):
Standard .....0.038 - 0.065 mm (0.0015 - 0.0026 inch)
Limit .....0.080 mm (0.0031 inch)

6. If it exceeds the limit, replace bearing.
7. If clearance cannot be adjusted within the standard of any bearing, grind crankshaft journal and use undersized bearing.






a. When grinding crankshaft journal, confirm that "L" dimension in fillet roll is more than the specified limit.

"L": .....0.1 mm (0.004 inch)

b. For grinding crankshaft to specifications, and available service parts. Refer to Engine; Specifications; Mechanical.






8. If crankshaft is reused, measure main bearing clearances and select thickness of main bearings.
If crankshaft is replaced with a new one, it is necessary to select thickness of main bearings as follows:

a. 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.






b. Grade number of each crankshaft main journal is punched on the respective crankshaft. These numbers are punched in either Arabic or Roman numerals.
c. Select main bearing with suitable thickness according to the table.

No. 1 main bearing grade number (Identification color):

Except No. 1 main bearing grade number (Identification color):

Connecting Rod Bearing (Big End)
1. Install connecting rod bearing to connecting rod and cap.
2. Install connecting rod cap to connecting rod.
Tighten bolts to the specified torque.

3. Measure inner diameter "C" of each bearing.






4. Measure outer diameter "Dp" of each crankshaft pin journal.
5. Calculate connecting rod bearing clearance.

Connecting rod bearing clearance (C - Dp):
Standard .....0.024 - 0.064 mm (0.0009 - 0.0025 inch)
Limit .....0.090 mm (0.0035 inch)

6. If it exceeds the limit, replace bearing.
7. If clearance cannot be adjusted within the standard of any bearing, grind crankshaft journal and use undersized bearing. Refer to Engine; Specifications; Mechanical.



CAUTION: Do not turn crankshaft or connecting rod while plastigage is being inserted.
When bearing clearance exceeds the specified limit, ensure that the proper bearing has been installed. Then if excessive bearing clearance exists, use a thicker main bearing or undersized bearing so that the specified bearing clearance is obtained.









Method B (Using plastigage)
CONNECTING ROD BUSHING CLEARANCE (SMALL END)
1. Measure inner diameter "C" of bushing.
2. Measure outer diameter "Dp" of piston pin.
3. Calculate connecting rod bushing clearance.

Connecting rod bushing clearance = C - Dp
Standard: .....0.005 - 0.017 mm (0.0002 - 0.0007 inch)
Limit: .....0.023 mm (0.0009 inch)

If it exceeds the limit, replace connecting rod assembly or connecting rod bushing and/or piston set with pin.







Inspection
FLYWHEEL/DRIVE PLATE RUNOUT

Runout (Total indicator reading):
Flywheel (M/T model) .....Less than 0.15 mm (0.0059 inch)
Drive plate (A/T model) ......Less than 0.15 mm (0.0059 inch)

CAUTION: Be careful not to damage the ring gear teeth.
Check the drive plate for deformation or cracks.
Do not allow any magnetic materials to contact the gear teeth.
Do not surface flywheel or drive plate. Replace as necessary.