Cylinder Block Assembly: Service and Repair

Legend
1 Oil level gauge guide
2 Cylinder block
3 Rear oil seal retainer
4 Rear oil seal
5 Rear plate
6 Flywheel
7 Rear plate cover
8 Drive plate
9 Drain plug
10 Buffer plate
11 Top ring
12 Oil ring
13 Piston
14 Snap ring
15 Piston pin
16 Connecting rod
17 Connecting rod bearing
18 Connecting rod cap
19 Key
20 Main bearing
21 Thrust bearing
22 Crankshaft
23 Main bearing cap

CAUTION:
- When installing sliding parts such as bearings and pistons, apply engine oil on the sliding surfaces.
- 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 of nuts.
- Do not allow any magnetic materials to contact the ring gear teeth of flywheel or drive plate, and rear plate.





DISASSEMBLY
PISTON AND CRANKSHAFT
1. Place engine on a work stand.
2. Drain coolant and oil.
3. Remove timing chain.





4. Remove pistons with connecting rod.
- When disassembling piston and connecting rod, remove snap ring first. Then heat piston to 60 to 70°C (140 to 158°F) or use piston pin press stand at room temperature.

CAUTION:
- When piston rings are not replaced, make sure that piston rings are mounted in their original positions.
- When replacing piston rings, if there is no punch mark, install with either side up.





5. Loosen main bearing caps in numerical order as shown in image.
6. Remove bearing caps, main bearings and crankshaft.
- Before removing bearing caps, measure crankshaft end play.
- Bolts should be loosened in two or three steps.





INSPECTION
PISTON AND PISTON PIN CLEARANCE
1. Measure inner diameter of piston pin hole "dp".
Standard diameter "dp":
18.987 - 18.999 mm (0.7475 - 0.7480 in)






2. Measure outer diameter of piston pin "Dp".
Standard diameter "Dp":
18.989 - 19.001 mm (0.7476 - 0.7481 in)

3. Calculate piston pin clearance.
Dp - dp = -0.004 to 0 mm (-0.0002 to 0 in)

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





PISTON RING SIDE CLEARANCE
Side clearance:
Top ring
0.040 - 0.080 mm (0.0016 - 0.0031 in)
Max. limit of side clearance:
0.1 mm (0.004 in)

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





PISTON RING END GAP
End gap:
Top ring 0.20-0.40 mm (0.0079 - 0.0157 in)
Oil ring 0.20-0.60 mm (0.0079 - 0.0236 in)
Max. limit of ring gap:
Top ring 0.49 mm (0.0193 in)
Oil ring 0.69 mm (0.0272 in)

If out of specification, replace piston ring. If gap exceeds maximum limit with a new ring, 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 in) per 100 mm (3.94 in) length
Torsion:
Limit 0.3 mm (0.012 in) per 100 mm (3.94 in) 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 10 check the flatness of cylinder block surface. Check along six positions shown in image.
Limit:
0.1 mm (0.004 in)

If out of specification, resurface it. The limit for cylinder block resurfacing is determined by the amount of cylinder head resurfacing.





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 in)
Nominal cylinder block height from crankshaft center:
213.95-214.05 mm (8.4232 - 8.4271 in)

If necessary, replace cylinder block.





PISTON-TO-BORE CLEARANCE
1. Using a bore gauge, measure cylinder bore for wear, out- of-round and taper.
Standard inner diameter:
76.000 - 76.030 mm (2.9921 - 2.9933 in)
Wear limit: 0.2 mm (0.008 in)

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

Out-of-round (X - Y) standard: 0.015 mm (0.0006 in)
Taper (A - B) standard: 0.01 mm (0.0004 in)

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





- If cylinder block or piston is replaced, match piston grade with grade number on cylinder block lower surface.





3. Measure piston skirt diameter.
Piston diameter "A":
Refer to Specifications.
Measuring point "a" (Distance from the bottom):
9.9 mm (0.390 in)

4. Check that piston-to-bore clearance is within specification.
Piston-to-bore clearance = cylinder bore measurement "B" - Piston diameter "A":
0.015 - 0.035 mm (0.0006 - 0.0014 in)

5. Determine piston oversize according to amount of cylinder wear.

Oversize pistons are available for service.

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 in)

7. Install main bearing caps and tighten bolts to the specified torque. This will prevent distortion of cylinder bores.
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 in) or so 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)
Less than 0.005 mm (0.0002 in)
Taper (A - B):
Less than 0.005 mm (0.0002 in)





3. Measure crankshaft runout.
Runout (Total indicator reading):
Less than 0.05 mm (0.0002 in)

BEARING CLEARANCE
- Use Method A or Method B. Method A is preferred because it is more accurate.





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 main journal in crankshaft.
5. Calculate main bearing clearance.
Main bearing clearance = A - Dm
Standard: 0.018 - 0.042 mm (0.0007 0.0017 in)
Limit: 0.1 mm (0.004 in)

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





When grinding crank pin and crank journal:
- Grind until clearance is within specified standard bearing clearance.
- Fillets should be finished as shown in the image.
R: 2.3 - 2.5 mm (0.091 - 0.098 in)

Refer to specifications for standard bearing clearance and available spare parts.





6. If the crankshaft or cylinder block is replaced, 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 image.





For example:
Cylinder block main journal grade number: 1
Crankshaft main journal grade number: 2
Main bearing grade number = 1 + 2 = Yellow

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: 0.010 - 0.035 mm (0.0004 - 0.0014 in)
Limit: 0.1 mm (0.004 in)

If it exceeds the limit, replace bearing.
If clearance cannot be adjusted using any standard bearing grade, grind crankshaft journal and use undersized bearing.








- If a new bearing, crankshaft or connecting rod is replaced, select connecting rod bearing according to the image.





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. Then if excessive bearing clearance exists, use a thicker main bearing or undersized bearing so that the specified bearing clearance is obtained.

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 in)
Limit:
0.023 mm (0.0009 in)

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





REPLACEMENT OF CONNECTING ROD BUSHING
(Small end)
1. Drive in small end bushing until it is flush with end surface of rod.

Be sure to align the oil holes.

2. Ream the bushing so that clearance with piston pin is within specification.
Clearance between connecting rod bushing and piston pin: 0.005 - 0.017 mm (0.0002 - 0.0007 in)





FLYWHEEL/DRIVEPLATE RUNOUT
Runout (Total indicator reading):
Flywheel (M/T models)
Less than 0.15 mm (0.0059 in)
Drive plate (A/T models)*
Less than 0.2 mm (0.008 in)
*Measuring points: Approximately 115 mm
(4.53 in) from crankshaft center

CAUTION:
Do not allow any magnetic materials to contact the ring gear teeth and rear plate.





ASSEMBLY
PISTON
1. Install new snap ring on one side of piston pin hole.





2. Heat piston to 60 to 70°C (140 to 158°F) and assemble piston, piston pin, connecting rod and new snap ring.
- Align the direction of piston and connecting rod.
- Numbers stamped on connecting rod and cap correspond to each cylinder.
- After assembly, make sure connecting rod swings smoothly.





3. Set piston rings as shown.

CAUTION:
- When piston rings are not replaced, make sure that piston rings are mounted in their original position.
- When piston rings are being replaced and no punch mark is present, piston rings can be mounted with either side up.

- Align piston rings so that end gaps are positioned as shown.

CRANKSHAFT
1. Set main bearings in their proper positions on cylinder block and main bearing cap.
- Confirm that correct main bearings are used.





2. Install crankshaft and main bearing caps and tighten bolts to the specified torque.
- Apply new engine oil to the bolt thread and seat surface.
- Prior to tightening bearing cap bolts, place bearing cap in its proper position by shifting crankshaft in the axial direction.





- Tighten bearing cap bolts gradually in two or three stages. Start with center bearing and move outward as shown in image.
- After securing bearing cap bolts, make sure crankshaft turns smoothly by hand.





3. Measure crankshaft end play.
Crankshaft end play:
Standard
0.060 - 0.180 mm (0.0024 - 0.0071 in)
Limit
0.3 mm (0.012 in) If beyond the limit, replace thrust bearing with a new one.





4. Install connecting rod bearings in connecting rods and connecting rod caps..
- Confirm that correct bearings are used.
- Install bearings so that oil hole in connecting rod aligns with oil hole of bearing.





5. Install pistons with connecting rods.
a. Install them into corresponding cylinders with Tool.
- Make sure connecting rod does not scratch cylinder wall.
- Make sure connecting rod bolts do not scratch crankshaft pin journals.
- Arrange so that front mark on piston head faces engine front.





b. Install connecting rod caps.

Apply new engine oil to bolt threads and nut seating surfaces.
Tighten connecting rod cap nuts in the following procedure:
1) Tighten to 13.72 to 15.68 Nm (1.399 to 1.599 kg-m, 10.120 - 11.566 ft-lb).
2) Turn nuts to 35 to 40 degrees clockwise with an angle wrench. If an angle wrench is not available, tighten nuts to 23 to 28 Nm (2.3 to 2.9 kg-m, 17 to 21 ft-lb).





6. Measure connecting rod side clearance.
Connecting rod side clearance:
Standard
0.200 - 0.470 mm (0.0079 - 0.0185 in)
Limit
0.50 mm (0.0197 in)
If beyond the limit, replace connecting rod and/or crankshaft.





7. Install rear oil seal retainer.
a. Before installing rear oil seal retainer remove old liquid gasket from cylinder block and retainer.
b. Apply a continuous bead of liquid gasket to rear oil seal retainer.
- Apply around inner side of bolt holes.