Inspection / Repair
CYLINDER HEAD
1. Measure the cylinder head for distortion in the six directions as shown.
Distortion: 0.10 mm (0.004 inch) max.
2. Inspect for the following and repair or replace.
1) Sunken of valve seats
2) Damaged intake and exhaust manifold contact surfaces
3) Excessive camshaft oil clearances and end play
3. If the cylinder head distortion exceeds specification, grind the surface or replace the cylinder head.
Grinding: 0.15 mm (0.006 inch) max.
4. If the cylinder head height is not within specification, replace it.
Height: 133.4 - 133.6 mm (5.252 - 5.259 inch)
5. Measure the intake and exhaust contact surfaces for distortion in the six directions as shown.
Distortion: 0.10 mm (0.0039 inch) max.
6. If distortion exceeds specification, grind the surface or replace the cylinder head.
Grinding: 0.15 mm (0.006 inch) max.
VALVE MECHANISM
Valve and Valve Guide
1. Measure the valve head margin thickness. Replace the valve if necessary.
Margin thickness
IN: 0.9 mm (0.0354 inch) min.
EX: 1.0 mm (0.0394 inch) min.
2. Measure the valve length. Replace the valve if necessary.
Length
Standard
IN: 93.91 mm (3.697 inch)
EX: 94.99 mm (3.740 inch)
Minimum
IN: 93.41 mm (3.678 inch)
EX: 94.49 mm (3.720 inch)
3. Measure the valve stem diameter in X and Y directions at three points (A,B and C) as shown. Replace the valve if necessary.
Diameter
IN: 5.970 - 5.985 mm (0.2351 - 0.2356 inch)
EX: 5.965 - 5.980 mm (0.2349 - 0.2354 inch)
Minimum
IN: 5.920 mm (0.2331 inch)
EX: 5.915 mm (0.2329 inch)
4. Measure the valve guide inner diameter in X and Y directions at three points (A, B and C) as shown. Replace the guide if necessary.
Inner diameter
IN: 6.01 - 6.03 mm (0.2367 - 0.2374 inch)
EX: 6.01 - 6.03 mm (0.2367 - 0.2374 inch)
5. Calculate the valve stem-to-guide clearance. Subtract the valve stem outer diameter from the inner diameter of the corresponding valve guide.
Clearance
IN: 0.025 - 0.060 mm (0.0010 - 0.0023 inch)
EX: 0.030 - 0.065 mm (0.0012 - 0.0025 inch)
Maximum: 0.20 mm (0.008 inch)
6. If the clearance exceeds the maximum, replace the valve and/or valve guide.
7. Measure the valve guide projection height (dimension (A)). Replace the guide if necessary.
Dimension (A)
IN: 14.7 - 15.3 mm (0.579 - 0.602 inch)
EX: 12.2 - 12.8 mm (0.481 - 0.503 inch)
Replacement of valve guide
NOTE: The intake and exhaust valve guides are the same.
1. Remove the valve guide from the combustion chamber side by using the Special Service Tool (SST).
2. Assemble the SST so that the depth L is as specified.
Depth L
IN: 14.7 - 15.3 mm (0.579 - 0.602 inch)
EX: 12.2 - 12.8 mm (0.481 - 0.503 inch)
3. Tighten the nut.
4. Tap the valve guide in from the side opposite the combustion chamber until the SST contacts the cylinder head.
5. Verify that the valve guide projection height is within specification.
Height
IN: 14.7 - 15.3 mm (0.579 - 0.602 inch)
EX: 12.2 - 12.8 mm (0.481 - 0.503 inch)
6. If not, repeat steps 1 - 4.
Valve seat
1. If necessary, resurface the valve seat by using a 45° valve seat cutter and/or resurface the valve face.
2. Apply a thin coat of Prussian blue to the valve face.
3. Check the valve seating by pressing the valve against the seat.
1) If blue does not appear 360° around the valve face, replace the valve.
2) If blue does not appear 360° around the valve seat, resurface the seat.
4. Measure the seat contact width.
Width: 0.8 - 1.4 mm (0.032 - 0.055 inch)
5. Verify that the valve seating position is at the center of the valve face.
1) If the valve seating position on the valve face is too high, correct the valve seat with a 75° cutter.
2) If the valve seating position of the valve face is too low, correct the valve seat with a 45° cutter.
6. Seat the valve to the valve seat by using a lapping compound.
7. Check the sinking of the valve seat.
1) Measure the protruding length (dimension L) of the valve stem.
Dimension L: 41.5 mm (1.634 inch)
2) If L is as below, it can be used as it is.
41.5 - 42.0 mm (1.634 - 1.653 inch)
3) If L is more than below, replace the cylinder head.
43.1 mm (1.697 inch) max.
Valve spring
1. Check the following pressure. Replace the valve spring if necessary.
Standard
IN: 37.0 mm (1.457 inch) with a set load of 237.6 - 268.8 Nm (53.29 - 60.30 lbs.)
EX: 38.7 mm (1.524 inch) with a set load of 233.0 - 263.6 Nm (52.25 - 59.13 lbs.)
2. Measure the out-of-square of the spring. Replace the valve spring if necessary.
Out-of-square: 1.63 mm (0.064 inch) max.
CAMSHAFT
1. Visually inspect the helical gears and the friction gear.
2. If a problem is found with the helical gear, replace the camshaft assembly.
3. If a problem is found with the friction gear, replace the friction gear as follows.
1) Secure the camshaft cast hexagon in a vise protected with-aluminum plates.
2) Loosen the locknut and remove the friction gear.
3) Align the matching marks and assemble the new friction gear.
Tightening torque:
69 - 78 Nm (51 - 57 ft. lbs.)
4. Set the No. 1 and No. 5 journals on V-blocks.
Measure the camshaft runout at the No. 2 - No. 4 journals. Replace the camshaft if necessary.
Runout: 0.02 mm (0.0008 inch) max.
5. Measure the cam lobe height at the two points (A and B) as shown. Replace the camshaft if necessary.
Height
6. Measure the journal diameters in X and Y directions at four points (A and B) as shown. Replace the camshaft if necessary.
Journal diameter
7. Measure the camshaft oil clearance with the HLA removed.
1) Install the camshafts so that the intake camshaft gear mark and exhaust camshaft gear mark align.
2) Position Plastigage atop each journal in the journal axial direction.
3) Do not rotate the camshaft when measuring the oil clearance.
4) Install the thrust caps.
5) Install the camshaft caps.
CAUTION: Remove the thrust caps only after removing all camshaft caps. Otherwise, the thrust caps can be damaged.
6) Loosen the camshaft cap bolts in five or six steps in the order shown.
7) Remove the camshaft caps.
8) Measure the oil clearance. If the oil clearance exceeds the maximum, replace the camshaft or the cylinder head.
Oil clearance
No.1, No. 5: 0.040 - 0.081 mm (0.0016 - 0.0031 inch)
No.2 - No. 4: 0.070 - 0.111 mm (0.0028 - 0.0043 inch)
Maximum
No.1, No. 5: 0.120 mm (0.0047 inch)
No.2 - No. 4: 0.150 mm (0.0059 inch)
8. Measure the camshaft end play. Replace the camshaft or the cylinder head if necessary.
End play: 0.05 - 0.10 mm (0.0020 - 0.0039 inch)
Maximum: 0.14 mm (0.0055 inch)
HLA
1. With the HLA filled with engine oil, hold (A) and press (B) by hand. If (B) moves, replace the HLA-do not attempt to repair it.
2. Measure the HLA bores in X and Y directions at two points (A and B) as shown.
Distortion: 30.000 - 30.025 mm (1.1811 - 1.1820 inch)
3. Measure the HLA diameters in X and Y directions at two points (A and B) as shown.
Diameter: 29.959 - 29.975 mm (1.1795 - 1.1801 inch)
4. Calculate the clearance between the HLA diameter and the related HLA bore. Replace the HLA and/or cylinder head if necessary.
Clearance:
0.025 - 0.066 mm (0.00099 - 0.00259 inch)
Maximum:
0.180 mm (0.0071 inch)
CYLINDER BLOCK
1. Measure the cylinder block decks for distortion in six directions as shown. Replace the cylinder block if necessary.
Distortion: 0.15 mm (0.0059 inch) max.
2. Measure the cylinder bores in X and Y directions at three points (A,B and C) as shown.
Cylinder bore
Base the boring diameter on the diameter of an oversize piston. All cylinders must be the same diameter.
Maximum: 0.15 mm (0.0059 inch)
1) If the cylinder bore exceeds the maximum, replace the cylinder block or rebore the cylinder to oversize.
2) If the difference between measurements A and C exceeds the maximum taper, replace the cylinder block or rebore the cylinder to oversize.
Taper: 0.022 mm (0.0009 inch) max.
3) If the difference between measurements X and Y exceeds the maximum out-of-round, rebore the cylinder to oversize.
Out-of-round: 0.020 mm (0.0008 inch) max.
4) If the upper part of a cylinder wall shows uneven wear, remove the ridge with a ridge reamer.
OIL JET
Apply compressed air of 216 - 274 kPa (32 - 39 psi) to the oil jet.
If air does not pass through the oil jet, replace it.
PISTON, PISTON RING, AND PISTON PIN
Piston
1. Measure the diameter of each piston at a right angle 90° to the piston pin, 16.5 mm (0.65 inch) below the oil ring groove lower edge.
Piston Diameter Chart
2. Measure the piston-to-cylinder clearance.
Clearance: 0.028 - 0.056 mm (0.0012 - 0.0022 inch)
Maximum: 0.13 mm (0.0051 inch)
3. If the clearance exceeds the maximum, replace the piston or rebore the cylinders to fit oversize pistons.
4. If the piston is replaced, the piston rings must also be replaced.
Piston and piston ring
1. Measure the piston groove clearance around the entire circumference by using a new piston ring.
Clearance
Top: 0.020 - 0.065 mm (0.0008 - 0.0025 inch)
Second: 0.030 - 0.065 mm (0.0012 - 0.0025 inch)
Oil: 0.025 - 0.052 mm (0.0010 - 0.0020 inch)
Maximum: 0.15 mm (0.0059 inch)
2. If the clearance exceeds the maximum, replace the piston
3. Insert the piston ring into the cylinder by hand and use the piston pin to push it to the bottom of the ring travel.
4. Measure each piston ring end gap.
5. If the clearance exceeds the maximum, replace the piston ring if necessary.
End gap
Top: 0.15 - 0.03 mm (0.0060 - 0.0118 inch)
Second: 0.25 - 0.40 mm (0.0099 - 0.0157 inch)
Oil rail: 0.20 - 0.70 mm (0.0079 - 0.0275 inch)
Maximum: 1.0 mm (0.0394 inch)
Piston and piston pin
1. Measure the piston pin bore in X and Y directions at eight points (A,B,C and D) as shown.
Diameter:
19.988 - 20.000 mm (0.7870 - 0.7874 inch)
2. Measure the piston pin diameter in X and Y directions at eight points (A, B, C and D) as shown.
Diameter:
19.974 - 19.980 mm (0.7864 - 0.7866 inch)
3. Calculate the piston pin-to-piston clearance.
Clearance: 0.008 - 0.026 mm (0.0004 - 0.0010 inch)
4. If the clearance exceeds specification, replace the piston and/or piston pin.
CONNECTING ROD
1. Measure the connecting rod small end bore.
Diameter: 19.943 - 19.961 mm (0.7852 - 0.7858 inch)
2. Calculate the interference between the small end bore and piston pin. Replace the connecting rod if necessary.
Interference: 0.013 - 0.037 mm (0.0006 - 0.0014 inch)
If the connecting rod is replaced, the connecting rod cap and bolts must also be replaced because they are a matched set.
3. Measure the connecting rod bending. Replace the connecting rod if necessary.
Bend: 0.05 mm (0.0020 inch) /50 mm (1.9685 inch)
Length (Center to Center):
137.80 - 137.90 mm (5.4252 - 5.4291 inch)
CRANKSHAFT
1. Set the crankshaft No. 1 and No. 4 journals on V-blocks.
2. Measure the crankshaft runout at the No.2 and No.3 journals. Replace the crankshaft if necessary.
Runout: 0.015 mm. (0.0006 inch) max.
3. Measure each journal diameter in X and Y directions at two points (A and B) as shown.
Main journal
Diameter:
61.938 - 61.955 mm (2.4385 - 2.4391 inch)
Out-of-round: 0.05 mm (0.002 inch) max.
Crank pin journal
Diameter:
52.940 - 52.955 mm (2.0843 - 2.0848 inch)
Out-of-round: 0.05 mm (0.002 inch) max.
4. If the diameter is less than the specification, replace the crankshaft or grind the journals to match undersize bearings.
Undersize bearing: 0.25 mm (0.01 inch)
Main journal diameter undersize
Crank pin journal diameter undersize
TIMING BELT AUTO TENSIONER
1. Measure the auto tensioner rod projection (a). Replace the auto tensioner if necessary.
Projection (A) (Free length):
14 - 16 mm (0.56 - 0.62 inch)
2. Check the auto tensioner for oil leakage. Replace the auto tensioner if necessary.