Cylinder Block Assembly: Service and Repair
When installing buffer rods, adjust the length between bolts of buffer rods as shown.
WARNING:
a. Situate vehicle on a flat and solid surface.
b. Place chocks at front and back of rear wheels.
c. Do not remove engine until exhaust system has completely cooled off. Otherwise, you may burn yourself and/or fire may break out in fuel line.
d. For safety during subsequent steps, the tension of wires should be slackened against the engine.
e. Before disconnecting fuel hose, release fuel pressure from fuel line.
f. Before removing front axle from transaxle, place safety stands under designated front supporting points.
g. Be sure to hoist engine and transaxle in a safe manner.
h. For engines not equipped with engine slingers, attach proper slingers and bolts.
CAUTION:
^ When lifting engine, be careful not to strike adjacent parts, especially accelerator wire casing, brake lines, and brake master cylinder.
^ In hoisting the engine, always use engine slingers in a safe manner.
^ In removing drive shaft, be careful not to damage grease seal of transaxle.
CAUTION:
^ When Installing sliding parts such as bearings and pistons be sure to apply engine oil on the sliding surfaces.
^ Place removed parts such as bearings and bearing caps in their proper order and direction.
^ When tightening connecting rod bolts and main bearing cap bolts, apply engine oil to thread portion of bolts and seating surface of nuts.
Disassembly
PISTON AND CRANKSHAFT
1. Place engine on a work stand.
2. Remove timing belt.
3. Drain coolant and remove water pump.
4. Drain oil.
5. Remove oil pan and oil pump.
6. Remove cylinder head.
7. Remove pistons.
^ When disassembling piston and connecting rods 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.
8. Remove bearing cap and crankshaft.
^ Before removing bearing cap, 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":
20.999 - 20.981 mm (0.8255 - 0.8280 in)
2. Measure outer diameter of piston pin "Dp".
Standard diameter "Dp":
20.971 - 20.983 mm (0.8258 - 0.8281 in)
3. Calculate piston pin clearance.
dp - Dp = 0 to -0.004 mm (0 to -0.0002 in)
If it exceeds the above value, replace piston assembly with pin.
PISTON RING SIDE CLEARANCE
Side clearance:
Top ring
0.040- 0.973 mm (0.0016 - 0.0029 in)
2nd ring
0.030- 0.063 mm (0.0012 - 0.0025 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
0.21-0.44 mm (0.0083 - 0.0173 in)
2nd ring
0.18-0.44 mm (0.0071 - 0.0173 in)
Oil ring
0.20-0.76 mm (0.0079 - 0.0299 in)
Max. limit of ring gap:
1.0 mm (0.039 in)
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.
CONNECTING ROD BEND AND TORSION
Bend:
Limit 0.1 mm (0.004 in) per 100 mm (3.94 in) length
Torsion:
Limit 0.30 mm (0.0118 in) per 100 mm (3.94 in) length
If it exceeds the limit, replace connecting rod assembly.
CYLINDER BLOCK DISTORTION AND WEAR
1. Clean upper face of cylinder block and measure the distortion.
Limit:
0.10 mm (0.0039 in)
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 in)
Nominal cylinder block height from crankshaft center:
227.60-227.70 mm (8.9608-8.9645 in)
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:
87.000-87.030 mm (3.252 - 3.284 in)
Wear limit:
0.20 mm (0.0079 in)
Out-of-round X - Y) limit:
0.015 mm (0.0008 in)
Taper (A - B) limit:
0.015 mm (0.0008 in)
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 one, select piston of the came grade number punched on cylinder block upper surface.
3. Measure piston skirt diameter.
Piston diameter "A":
Measuring point "a" (Distance from the bottom):
18 mm (0.71 in)
4. Check that piston-to-bore clearance is within specification.
Piston-to-bore clearance "B":
0.015 - 0.035 mm (0.0008 - 0.0014 in)
5. Determine piston oversize according to amount of cylinder wear.
Note: Oversize pistons are available for service.
6. Cylinder bore size is determined by adding piston-to-bore clearance to piston diameter "A".
Rebore 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 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 in) 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)
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 0.10 mm (0.0039 in)
BEARING CLEARANCE
^ Either of the following two methods may be used, 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 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
0.028 - 0.055 mm (0.0011 - 0.0022 in)
Limit
0.090 mm (0.0035 in)
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 in)
b. Refer to Specifications for grinding crankshaft and available service parts.
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.
b. Grade number of each crankshaft main journal is punched on the respective crankshaft.
c. Select main bearing with suitable thickness according to the image.
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
0.014 - 0.054 mm (0.0008 - 0.0021 in)
Limit
0.090 mm (0.0035 in)
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 7 of "BEARING CLEARANCE - Main bearing".
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 md bushing clearance = C - Dp
Standard: 0.005 - 0.017 mm (0.0002 - 0.0007 in)
Limit: 0.028 mm (0.0009 in)
If it exceeds the limit, replace connecting rod assembly or connecting rod bushing 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. After driving in small end bushing, ream the bushing so that clearance between connecting rod bushing and piston pin is the specified value.
Clearance between connecting and bushing and piston pin:
0.005 - 0.017 mm (0.0002 - 0.0007 in)
FLYWHEEL/DRIVE PLATE RUNOUT
Runout (Total Indicator reading):
Flywheel (M/T model)
Less than 0.15 mm (0.0059 in)
Drive plate (A/T model)
Less than 0.15 mm (0.0059 in)
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 pins 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 in image.
CRANKSHAFT
1. Set main bearings in their proper positions on cylinder block and main bearing cap.
^ Confirm that correct main bearings are used. Refer to "inspection".
2. Install crankshaft and main bearing caps and tighten bolts to the specified torque.
^ 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 sequentially.
^ After securing bearing cap bolts. make sure crankshaft turns smoothly by hand.
3. Measure crankshaft end play.
Crankshaft end play:
Standard
0.050 - 0.170 mm (0.0020 - 0.0067 in)
Limit
0.30 mm (0.0118 in)
If beyond the limit, replace bearing with a new one.
4. install connecting rod bearings in connecting rods and connecting rod caps.
^ Confirm that correct bearings are used. Refer to "Inspection".
^ 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.
^ Be careful not to scratch cylinder wall by connecting rod.
^ Arrange so that front mark on piston head faces toward front of engine.
b. Install connecting rod bearing caps. Tighten connecting rod bearing cap nuts to the specified torque.
Tighten: Connecting rod bearing nut
(1)
Tighten to 14 to 18 N.m (1.4 to 1.6 kg-m, 10 to 12 ft-lb).
(2)
Turn nuts 60 to 65 degrees clockwise. If an angle wench is not available, tighten nuts to 38 to 44 N.m, (3.9 to 4.5 kg-m, 28 to 38 ft-lb).
6. Measure connecting rod side clearance. Connecting rod aide clearance:
Standard
0.20-0.35 mm (0.0079 - 0.0138 in)
Limit
0.40 mm (0.0157 in)
If beyond the limit. replace connecting rod and/or crankshaft.