Inspection

CYLINDER BLOCK

Inspection


PISTON AND PISTON PIN CLEARANCE

Inner Diameter of Piston Pin Hole





- Measure the inner diameter of piston pin hole (dp).





Outer Diameter of Piston Pin





- Measure outer diameter of piston pin (Dp).















Piston and Piston Pin Interference Fit
Standard Interference Fit = (Dp) - (dp)





- If clearance is exceeds specification, replace either or both of piston/piston pin assembly and connecting rod assembly with reference to specification of each part.

PISTON RING SIDE CLEARANCE

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- Measure side clearance of piston ring and piston ring groove with feeler gauge.





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

PISTON RING END GAP






- Insert piston ring until it is in the middle of the cylinder bore and measure the end gap.





- If out of specification, replace piston ring.

CONNECTING ROD BEND AND TORSION
















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





CONNECTING ROD BUSHING OIL CLEARANCE (SMALL END)

Inner Diameter of Connecting Rod (Small End)





- Measure inner diameter of piston pin bushing.





Outer Diameter of Piston Pin





- Measure outer diameter of piston pin.





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)





- 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, use the Table for
Selective Fitting for Piston to select the piston corresponding to the applicable bore grade of the cylinder block to be used. Follow the
"PISTON-TO-CYLINDER BORE CLEARANCE" procedure.
Factory installed parts grading:
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Service parts apply only to grade 0.
Unit: mm (in)






CYLINDER BLOCK DISTORTION






- Using a scraper, remove any old gasket material on the cylinder block surface and remove any oil, scale, carbon, or other contamination.

CAUTION:
Be careful not to allow gasket flakes to enter the oil or coolant passages.
- Measure the distortion on the block upper face at different points in six directions.





- If out of specification, resurface the cylinder block. The allowable amount of resurfacing is dependent on the amount of any cylinder head resurfacing. The resurfacing limit is [amount of cylinder head resurfacing] + [amount of cylinder head resurfacing] = 0.2 mm (0.008 in).





INNER DIAMETER OF MAIN BEARING HOUSING

- Install the main bearing caps with the main bearings removed, and tighten the bolts to the specified torque.





- Using a bore gauge, measure the inner diameter of the main bearing housing (A).





- If out of the standard, replace the cylinder block and main bearing caps as an assembly.
NOTE:
These components cannot be replaced as a single unit, because they were processed together.

PISTON-TO-CYLINDER BORE CLEARANCE

1.Using a bore gauge, measure cylinder bore for wear, out-of-round and taper at (A), (B) and (C). The X axis is in the longitudinal direction of the engine.
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Cylinder bore inner diameter















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










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.










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





- The piston-to-bore clearance is measured at the (B) level in the cylinder as shown.
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5.Cylinder bore size is determined by adding piston-to-bore clearance to piston diameter (A).





6.Install main bearing caps, and tighten to the specified torque. Otherwise, cylinder bores may be distorted after boring.
7.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 in) or so in diameter at a time.
8.Hone cylinders to obtain specified piston-to-bore clearance.
9.Measure finished cylinder bore for out-of-round and taper.
-Measurement should be done after cylinder bore cools down.

CRANKSHAFT






1.Check the crankshaft main and pin journals for scoring, wear, or cracks.
2.Measure the journals for taper and out-of-round.










3.Measure crankshaft runout.
a.Place a V-block on a precise flat table to support the journals on the both ends of the crankshaft.
b.Place a dial gauge straight up on the No. 3 journal.
c.While rotating the crankshaft, read the movement of the pointer on the dial gauge.





BEARING CLEARANCE

- Use either of the following two methods, however method (A) gives more reliable results and so is the preferred method.
)
Main Bearing
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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. Refer to "Disassembly and Assembly" Disassembly and Assembly.





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)





- 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.





6.If the crankshaft or the cylinder block is replaced with a new one, select thickness of the main bearings as follows:
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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:





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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. Refer to "Disassembly and Assembly" Disassembly and Assembly.





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.





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.





- 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:
Do not 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)".

DRIVE PLATE RUNOUT

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Use a suitable tool to measure the runout (Total Indicator Reading)
as shown.





CAUTION:
- The signal plate is built into the drive assembly. Be careful not to damage the signal plate, particularly the teeth.





- Check the drive plate and signal plate for deformation or cracks.
- Keep all magnetized objects away from the signal plate, particularly the teeth.

OIL JET

- Check nozzle for deformation and damage.
- Blow compressed air from nozzle, and check for clogs.
- If it is not operating properly, replace oil jet.

OIL JET RELIEF VALVE






- Using a clean plastic stick, press check valve in oil jet relief valve.
Make sure that valve moves smoothly with proper reaction force.
- If it is not operating properly, replace oil jet relief valve.