Cylinder Block Assembly: Service and Repair
DISASSEMBLY
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.
PISTON AND CRANKSHAFT
1. Place engine on a work stand.
2. Drain coolant and oil.
3. Remove oil pan.
4. Remove timing chain.
5. Remove water pump.
6. Remove cylinder head.
7. Remove pistons with connecting rods.
8. Remove bearing caps 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": 20.993 - 21.005 mm (0.8265 - 0.8270 inch)
2. Measure outer diameter of piston pin "Dp".
Standard diameter "Dp": 20.989 - 21.001 mm (0.8263 - 0.8268 inch)
3. Calculate piston pin clearance.
dp - Dp = -0.002 - 0.01 mm (-0.0001 to 0.0004 inch)
If it exceeds the above value, replace piston assembly with pin.
PISTON RING SIDE CLEARANCE
Side clearance:
Top ring: 0.04 - 0.08 mm (0.0016 - 0.0031 inch)
2nd ring: 0.03 - 0.07 mm (0.0012 - 0.0028 inch)
Max. limit of side clearance: 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: 0.28 - 0.52 mm (0.0110 - 0.0205 inch)
2nd ring: 0.45 - 0.69 mm (0.0177 - 0.0272 inch)
(R or T is punched on the ring.)
0.55 - 0.70 mm (0.0217 - 0.0276 inch)
(N is punched on the ring.)
Oil ring: 0.20 - 0.69 mm (0.0079 - 0.0272 inch)
Max. limit of ring gap: Refer to Piston Ring, Engine; Specifications.
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. Refer to Piston Ring, Engine; Specifications.
^ When replacing the piston, check cylinder block surface for scratches or seizure. If scratches or seizure are 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
1. Clean upper face of cylinder block.
Use a reliable straightedge and feeler gauge to check the flatness of cylinder block surface. Check along six positions shown in figure.
Limit: 0.1 mm (0.004 inch)
2. If out of specification, resurface it.
The limit for cylinder block resurfacing is determined by 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 inch)
Nominal cylinder block height from crankshaft center: 246.95 - 247.05 mm (9.72241- 9.7264 inch)
3. 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:
Refer to Cylinder Block Assembly; Specifications.
Wear limit: 0.2 mm (0.008 inch)
Out-of-round (X - Y) standard: 0.015 mm (0.0006 inch)
Taper (A - B) standard: 0.010 mm (0.0004 inch)
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 cylinder block and piston are replaced, match piston grade with grade number on cylinder block upper surface.
3. Measure piston skirt diameter.
Piston diameter "A":
Refer to Piston, Engine; Specifications.
Measuring point "a" (Distance from the top):
Approximately 48 mm (1.89 inch)
4. Check that piston-to-bore clearance is within specification.
Piston-to-bore clearance "B": 0.020 - 0.040 mm (0.0008 - 0.0016 inch)
5. Determine piston oversize according to amount of cylinder wear.
Oversize pistons are available for service. Refer to Piston, Engine; Specifications.
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 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 inch) 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):
Main journal: Less than 0.01 mm (0.0004 inch)
Crank pin: Less than 0.005 mm (0.0002 inch)
Taper (A - B):
Main journal: Less than 0.01 mm (0.0004 inch)
Crank pin: Less than 0.005 mm (0.0002 inch)
3. Measure crankshaft runout.
Runout (Total indicator reading): Less than 0.10 mm (0.0039 inch)
BEARING CLEARANCE
^ Use Method A or Method B. Method A is preferred because it is more accurate.
Method A (Using bore gauge and 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.
Main bearing clearance = A - Dm
Standard: 0.020 - 0.047 mm (0.0008 - 0.0019 inch)
Limit: 0.1 mm (0.004 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. Refer to Crankshaft; Specifications for grinding crankshaft and available service parts.
8. If crankshaft is reused, measure main bearing clearance and select thickness of main bearing.
If 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 crankshaft. These numbers are punched in either Arabic or Roman numerals.
c. Select main bearing with suitable thickness according to the following example or table.
For example:
Main journal grade number: 1
Crankshaft journal grade number: 2
Main bearing grade number = 1 + 2 = 3 (Yellow)
Main bearing grade number and 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: 0.010 - 0.035 mm (0.0004 - 0.0014 inch)
Limit: 0.09 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 step 5 of "BEARING CLEARANCE".
8. If crankshaft is replaced, select connecting rod bearing according to the following table.
Connecting rod bearing grade number:
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. 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.
C - Dp = 0.005 - 0.017 mm (0.0002 - 0.0007 inch) (Standard)
0.023 mm (0.0009 inch) (Limit)
If out of specification, replace connecting rod assembly and/or piston set with 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. Rear the bushing until clearance with piston pin is within specification.
Clearance between connecting rod bushing and piston pin: 0.005 - 0.017 mm (0.0002 - 0.0007 inch)
FLYWHEEL/DRIVE PLATE RUNOUT
Runout (Total indicator reading):
Flywheel (M/T model): Less than 0.15 mm (0.006 inch)
Drive plate (A/T model): Less than 0.15 mm (0.006 inch)
CAUTION:
^ Be careful not to damage the ring gear teeth.
^ Check the drive plate for deformation and cracks.
^ Do riot allow any magnetic materials to contact the ring gear teeth.
^ Do not resurface the flywheel. Replace as necessary.
ASSEMBLY
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.
PISTON
1. Heat piston to 60 to 70°C (140 to 158°F) and assemble piston, piston pin and connecting rod.
^ 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.
2. Set piston rings as shown.
CAUTION:
^ When piston rings are not replaced, make sure that piston rings are mounted in their original positions.
^ When piston rings are being replaced and no punchmark is present, piston rings can be mounted with either side up.
3. 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 caps.
^ Confirm that correct main bearings are used.
^ Apply new engine oil to bearing surfaces.
2. Install crankshaft and main bearing caps and tighten bolts to the specified torque.
^ Apply new engine oil to the bolt threads 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 figure.
^ After securing bearing cap bolts, make sure crankshaft turns smoothly by hand.
3. Measure crankshaft end play.
Crankshaft end play:
Standard: 0.05 - 0.18 mm (0.0020 - 0.0071 inch)
Limit: 0.3 mm (0.012 inch)
If beyond the limit, replace No. 3 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.
^ Apply new engine oil to bearing surfaces, bolt threads and seating surfaces.
5. Install pistons with connecting rods.
a. Install them into corresponding cylinders with Tool.
^ Arrange so that front mark on piston head faces toward front of engine.
^ Make sure connecting rod does not scratch cylinder wall.
^ Make sure connecting rod bolts do not scratch crankshaft journals.
^ Apply new engine oil to piston rings and sliding surface of piston.
b. Install connecting rod bearing caps.
Tighten connecting rod bearing car) nuts using the following procedure.
Connecting rod bearing nut:
(1) Tighten to 14 - 16 Nm (1.4 - 1.6 kg-m, 10 - 12 ft. lbs.).
(2) Tighten bolts 60 +5/-0 degrees clockwise with an angle wrench.
If an angle wrench is not available, tighten them to 38 - 44 Nm (3.9 - 4.5 kg-m, 28 - 33 ft. lbs.).
6. Measure connecting rod side clearance.
Connecting rod side clearance:
Standard: 0.2 - 0.4 mm (0.008 - 0.016 inch)
Limit: 0.6 mm (0.024 inch)
If beyond the limit, replace connecting rod and/or crankshaft.
OIL SEAL INSTALLING DIRECTION
^ Install new oil seal in the direction shown.
REPLACING PILOT BUSHING
1. Remove pilot bushing (M/T) or pilot convertor (A/T).
2. Install pilot bushing (M/T) or pilot convertor (A/T).