Part 2
DISASSEMBLY
1. Remove the connecting rod cap.
2. Remove the connecting rod bearing.
NOTE: Arrange the removed connecting rod, connecting rod cap and bearing in order, to prevent confusion.
3. Remove the piston rings using piston ring expander.
4. Remove the oil ring by hand.
NOTE: Arrange the removed piston rings in proper order, to prevent confusion.
5. Remove the snap ring.
ASSEMBLY
Tightening torque:N-m (kgf-m, ft-lb)
T: 53 (5.4, 39. 1)
1. Apply oil to the surface of the connecting rod bearings, and install the bearings on the connecting rods and connecting rod caps.
2. Position each connecting rod with the marking side facing forward.
3. Install the connecting rod cap. Make sure the arrow mark on connecting rod cap facing front during installation.
CAUTION:
^ Each connecting rod has its own mating cap. Make sure that they are assembled correctly by checking their matching number.
^ When tightening the connecting rod bolts, apply oil on the threads and flange end.
Tightening torque: 53 N-m (5.4 kgf-m, 39.1 ft-lb)
4. Install the oil ring spacer, upper rail and lower rail by hand.
5. Install the second ring and top ring using piston ring expander.
INSPECTION
CYLINDER BLOCK
1. Check for cracks or damage. Use liquid penetrant tester on the important sections to check for fissures. Check that there are no marks of gas leaking or water leaking on gasket installing surface.
2. Check the oil passages for clogging.
3. Inspect the cylinder block surface that mates with cylinder head for warping by using a straight edge. If the warping exceeds the limit, replace the cylinder block.
Warping limit. 0.02 mm (0.0008 in)
Standard height of cylinder block. 202 mm (7.95 in)
CYLINDER AND PISTON
1. The cylinder bore size is stamped on the front upper face of the cylinder block.
NOTE:
^ Measurement should be performed at a temperature of 20 degrees C (68 degrees F).
^ Standard sized pistons are classified into two grades, "A" and "B". These grades should be used as guide lines in selecting a standard piston.
Standard diameter.
A: 89.205 - 89.215 mm (3.5120 - 3.5124 in)
B: 89.195 - 89.205 mm (3.5116 - 3.5120 in)
2. How to measure the inner diameter of each cylinder:
Measure the inner diameter of each cylinder in both the thrust and piston pin directions at the heights as shown in the figure, using a cylinder bore gauge.
NOTE: Measurement should be performed at a temperature of 20 degrees C (68 degrees F).
Cylindricality.
Standard 0.030 mm (0.0012 in)
Out-of-roundness:
Standard 0.010 mm (0.0004 in)
3. When the piston is to be replaced due to general or cylinder wear, determine a suitable sized piston by measuring the piston clearance.
4 How to measure the outer diameter of each piston:
NOTE: Measure the outer diameter of each piston at the height as shown in the figure. (Thrust direction)
NOTE: Measurement should be performed at a temperature of 20 degrees C (68 degrees F).
Piston grade point H. 37.3 mm (1) 4685 in)
Piston outer diameter.
Standard
A: 89.205 - 89.215 mm (3.5120 - 3.5124 in)
B: 89.195 - 89.205 mm (3.5116 - 3.5120 in)
0.25 mm (0.0098 in) oversize
89.445 - 89.465 mm (3.5215 - 3.5222 in)
0.50 mm (0.0197 in) oversize
89.695 - 89.715 mm (3.5313 - 3.5321 in)
5. Calculate the clearance between cylinder and piston.
NOTE: Measurement should be performed at a temperature of 20 degrees C (68 degrees F).
Cylinder to piston clearance at 20 degrees C (68 degrees F).
Standard -0.010 - 0.010 mm (-0.0004 - 0.0004 in)
6. Boring and honing:
1. If the value of cylindrically, out-of-roundness, or cylinder-to-piston clearance measured is out of standard or if there is any damage on the cylinder wall, rebore it to use an oversize piston.
CAUTION:
^ When any of the cylinders needs reboring, other cylinders must be bored at the same time, and replaced with oversize pistons.
^ Do not perform boring on one cylinder only. Do not replace only a single cylinder for an oversize piston.
2. If the cylinder inner diameter exceeds the limit after boring and honing, replace the cylinder block.
Cylinder inner diameter boring limit (diameter): To 89.715 mm (3.5321 in)
NOTE: Immediately after reboring, the cylinder diameter may differ from its real diameter due to temperature rise. Thus, pay attention to this when measuring the cylinder diameter.
PISTON AND PISTON PIN
1. Check the piston and piston pin for breaks, cracks or wear. Replace if faulty.
2. Check the piston ring groove for wear or damage. Replace if faulty.
3. Make sure that the piston pin can be inserted into the piston pin hole with a thumb at 20 degrees C (68 degrees F). Replace if faulty.
Standard clearance between piston pin and hole in piston:
Standard 0.004 - 0.008 mm (0.0002 - 0.0003 in)
4. Check the snap ring installation groove (A) on the piston for burr. If necessary, remove burr from the groove so that the piston pin can lightly move.
5. Check the piston pin snap ring for distortion, cracks and wear.
PISTON RING
1. If the piston ring is broken, damaged or worn, or if its tension is insufficient, or when the piston is replaced, replace the piston ring with a new part of the same size as piston.
NOTE:
^ The top ring and second ring have the mark to determine the direction to install on them. When installing the ring to piston, face this mark to the top side.
^ Oil ring consists of the upper rail, expander and lower rail. When installing on the piston, be careful of the direction of each rail.
2. Squarely place the piston ring and oil ring in cylinder, and measure the piston ring gap with a thickness gauge.
3. Fit the piston ring straight into the piston ring groove, then measure the clearance between piston ring and piston ring groove with a thickness gauge.
NOTE: Before measuring the clearance, clean the piston ring groove and piston ring.
CONNECTING ROD
1. Replace the connecting rod, if the large or small end thrust surface is damaged.
2. Check for bend or twist using a connecting rod aligner. Replace the connecting rod if it has the bend or twist.
3. Install the connecting rod fitted with bearing to crankshaft and measure the thrust clearance. If the thrust clearance exceeds the standard or uneven wear is found, replace the connecting rod.
Connecting rod thrust clearance:
Standard 0.070 - 0.330 mm (0.0028 - 0.0130 in)
4. Inspect the connecting rod bearing for scar, peeling, seizure, melting, wear, etc.
5. Measure the oil clearance on each connecting rod bearing using plastigauge. If any oil clearance is not within the standard, replace the defective bearing with a new part of standard size or undersize as necessary. (See the table below.)
Connecting rod oil clearance:
Standard 0.016 - 0.043 mm (0.0006 - 0.0017 in)
6. Inspect the bushing at connecting rod small end, and replace if worn or damaged.
7. Measure the piston pin clearance at connecting rod small end. If the measured value is not within the standard, replace it with a new part.
Clearance between piston pin and bushing:
Standard 0 - 0.022 mm (0 - 0.0009 in)
8. The replacement procedure for the connecting rod small end bushing is as follows.
1. Remove the bushing from connecting rod with ST and press.
2. Press the bushing with ST after applying oil on the periphery of bushing.
ST 18350AA000 CONNECTING ROD BUSHING REMOVER AND INSTALLER
3. Make two 3 mm (0.12 in) holes in the pressed bushing by aligning with the pre-manufactured holes on the connecting rod, and ream the inside of the bushing.
4. After completion of reaming, clean the bushing to remove chips.
CRANKSHAFT AND CRANKSHAFT BEARING
1. Clean the crankshaft completely, and check it for cracks using liquid penetrant tester. Replace if defective.
2. Check the crankshaft for bend, and repair or replace if needed. Repair or replace if bended.
NOTE: If a suitable V-block is not available, install #1 and #5 crankshaft bearing on cylinder block, position the crankshaft on these bearings, and then check the crankshaft bend using a dial gauge.
3. Inspect the crank journal and crank pin for wear. If they are not within the specification, replace the bearing with a suitable (undersize) one, and replace or readjust crankshaft as necessary. When grinding the crank journal or crank pin, finish them to the specified dimensions according to the undersize bearing to be used.
Crank pin and crank journal.
Out-of-roundness 0.005 mm (0.0002 in)
Cylindricality 0.006 mm (0.0002 in)
4. Measure the thrust clearance of crankshaft at center bearing by using thickness gauge. If the thrust clearance is not within the standard, replace the bearing.
Crankshaft thrust clearance:
Standard 0.030 - 0.115 mm (0.0012 - 0.0045 in)
5. Inspect individual crankshaft bearings for signs of flaking, seizure, melting and wear.
6. Measure the oil clearance on each crankshaft bearing using plastigauge. If the measured value is out of standard, replace the defective bearing with an undersize one, and replace or recondition the crankshaft as necessary.
Crankshaft oil clearance:
Standard 0.010 - 0.030 mm (0.0004 - 0.0012 in)