Inspection

Components

PISTON AND PISTON PIN CLEARANCE





1. Measure inner diameter of piston pin hole "dp".
Standard diameter"dp":
Grade No. 0 21.993 - 21.999 mm (0.8659 - 0.8661 inch)
Grade No. 1 21.999 - 22.005 mm (0.8661 - 0.8663 inch)





2. Measure outer diameter of piston pin "Dp".
Standard diameter "Dp":
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)
3. Calculate interference fit of piston pin to piston.
Dp - dp = 0.002 - 0.006 mm (0.0001 - 0.0002 inch)
If it exceeds the above value, replace piston assembly with pin.

PISTON RING SIDE CLEARANCE





Side clearance:
Top ring 0.045 - 0.080 mm (0.0018 - 0.0031 inch)
2nd ring 0.030 - 0.070 mm (0.0012 - 0.0028 inch)
Oil ring 0.065 - 0.135 mm (0.0026 - 0.0053 inch)

Maximum limit of side clearance:
Top ring 0.11 mm (0.0043 inch)
2nd ring 0.1 mm (0.004 inch)

If out of specification, replace piston ring. If clearance exceeds maximum limit with new ring, replace piston.

PISTON RING END GAP





End gap:
Top ring 0.23 - 0.33 mm (0.0091 - 0.0130 inch)
2nd ring 0.33 - 0.48 mm (0.0130- 0.0189 inch)
Oil ring 0.20 - 0.80 mm (0.0079 - 0.0315 inch)

Maximum limit of ring gap:
Top ring 0.54 mm (0.0213 inch)
2nd ring 0.80 mm (0.0315 inch)
Oil ring 0.95 mm (0.0374 inch)

If out of specification, replace piston ring.

If gap still exceeds the limit even with a new ring, do the following. Rebore cylinder and use oversized piston and piston rings.
^ When replacing the piston, check the cylinder block surface for scratches or seizure. If scratches or seizure is found, hone or replace the cylinder block.

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.

CYLINDER BLOCK DISTORTION AND WEAR





^ Clean upper surface of cylinder block.
Use a reliable straightedge and feeler gauge to check the flatness of cylinder block surface.
Check along six positions shown in the figure.
Distortion limit: 0.10 mm (0.0039 inch)
^ If out of specification, resurface it. The limit for cylinder block resurfacing is determined by cylinder head resurfacing in engine.
Resurfacing limit:
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: 214.95 - 215.05 mm (8.4626 - 8.4665 inch)
^ If necessary, replace cylinder block.

PISTON-TO-BORE CLEARANCE








1. Using a bore gauge, measure cylinder bore for wear, out-of-round and taper.
Cylinder bore inner diameter





If it exceeds the limit, rebore all cylinders. Replace cylinder block if necessary.
Out-of-round (Difference between X and Y): Limit 0.015 mm (0.0006 inch)
Taper (Difference between A and C): Limit 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 punched on cylinder block rear position. These numbers are punched in either Arabic or Roman numerals.





3. Measure piston skirt diameter.
Measuring point "a" (Distance from the top): 41.0 mm (1.61 inch)
4. Check that piston-to-bore clearance is within specification.
Piston-to-bore clearance "B": 0.010 - 0.030 mm (0.0004- 0.0012 inch)
5. Determine piston oversize according to amount of cylinder wear. Oversize pistons are available for service.
^ If oversize piston is used, use oversize piston ring also.

6. Cylinder bore size is determined by adding piston-to-bore clearance to piston diameter "A".
Rebored size calculation: D = A + B - C
where,
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.
Otherwise, cylinder bores may be distorted 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.

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):
Standard 0.002 mm (0.0001 inch)
Taper (A - B):
Standard 0.002 mm (0.0001 inch)





3. Measure crankshaft runout.
Runout (Total indicator reading): Limit 0.10 mm (0.0039 inch)

BEARING CLEARANCE
^ Use either of the following two methods, however, method "A" gives more reliable results and is preferable.

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 and bearing beam to cylinder block. Tighten all bolts in correct order.
3. Measure inner diameters "A" of each main bearing.





4. Measure outer diameters "Dm" of each crankshaft main journal.
5. Calculate 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 bearing.
^ If clearance cannot be adjusted using any standard bearing grade, 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. Refer to grinding crankshaft and available service parts.
6. If crankshaft or cylinder block is replaced with a new one, 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 Alphabet.
If measured diameter is out of grade punched, decide suitable grade.





b. Grade number of each crankshaft main journal is punched on the respective crankshaft. These numbers are punched in either Arabic or Alphabet.
If measured diameter is out of grade punched, decide suitable grade using table.
c. Select main bearing with suitable thickness according to the table.





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 connecting rod.





4. Measure outer diameter "Dp" of each crankshaft pin journal.
5. Calculate 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 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.





8. If crankshaft is replaced with a new one, select connecting rod bearing according to the table.
Connecting rod bearing grade number (Identification color):
These numbers are punched in either Arabic or Roman numerals.





Method B (Using Plastigage)





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. If incorrect bearing clearance exists, use a thicker or undersized main bearing to ensure specified clearance.

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: 0.030 mm (0.0012 inch)
If it exceeds the limit, replace connecting rod assembly or connecting rod bushing and/or piston set with pin.

FLYWHEEL/DRIVE PLATE RUNOUT





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

CAUTION:
^ Do not disassemble the flywheel.
^ Be careful not to damage the signal plate, especially the teeth.





^ Check the drive plate and signal plate for deformation or cracks.
^ Never place the flywheel assembly with the signal plate facing down.
^ Keep any magnetized objects away from the signal plate.
^ Do not allow any magnetic materials to contact the signal plate teeth.
^ Do not resurface flywheel. Replace as necessary.

MOVEMENT AMOUNT OF FLYWHEEL (M/T MODELS)

NOTE:
^ Inspection for double mass flywheel only.
^ Do not disassemble double mass flywheel.

Flywheel Deflection
^ Measure deflection of flywheel contact surface to the clutch with a dial gauge.





^ Measure deflection at 210 mm (8.27 inch) diameter
Standard: 0.45 mm (0.0177 inch) or less
Limit: 1.3 mm (0.051 inch) or less
^ When measured value exceeds the limit, replace it with a new one.

Movement Amount in Rotation Direction
^ Check the movement amount in the following procedure.

1. Install a bolt to clutch cover mounting hole, and place a torque wrench on the extended line of the flywheel center line.
^ Tighten bolt at a force of 9.8 Nm (1 kg-m, 87 inch lbs.) to keep it from loosening.





2. Put a mating mark on circumference of the two flywheel masses without applying any load (Measurement standard points).
3. Apply a force of 9.8 Nm (1 kg-m, 87 inch lbs.) in each direction, and mark the movement amount on the mass on the transmission side.
4. Measure dimensions of movement amounts A and B on circumference of the flywheel on the transmission side.
Standard: 24 mm (0.94 inch) or less
^ When measured value is outside the standard, replace flywheel.