2.
Remove scale, sealing compound and carbon deposits completely. After cleaning the oil passages, apply compressed air to verify that the passagesare not clogged.
Check the cylinder head for cracks, damage and coolant leakage. If cracked, replace the cylinder head.
Remove scale, sealing compound and carbon deposits completely. After cleaning the oil passages, apply compressed air to verify that the passagesare not clogged.
Check the cylinder head surface for flatness in the direction as shown in the illustration. If flatness exceeds service limit in any direction, either replace the cylinder head or machine the cylinder head matching surfacelightly.
Flatness of cylinder head gasket surface |
Standard : 0.03 mm (0.0012 in.) |
for width 0.09 mm (0.0035 in.) for length) |
0.012 mm (0.00047 in.) / 51 x 51 |
Using a wire brush, clean the valve thoroughly.
Check each valve for wear, damage and distortion of the head and the stem at B Position. Replace, if necessary. If stem end, A, is hollowed out or worn, resurface as necessary. This correction must be limited to aminimum. Also resurface the valve face.
Replace the valve if the margin has decreased to less than the service limit.
Margin |
[Standard] |
Intake : 1.6 mm (0.063 in.) |
Exhaust : 1.3 mm (0.0512 in.) |
Check the free height of each valve spring. If they exceed the service limit, replace the springs.
Using a square, test the squareness of each spring. If a spring is excessively out- of-square, replace it.
Valve spring |
[Standard] |
Free height : 39.14 mm(1.54 in.) |
Load : 21.4 kg / 32 mm (47.2 lb / 1.26 in.) |
Out of square : 1.5° or less |
[Limit] |
Free height : 38.14 mm (1.50 in.) |
Out of square : 4° |
Valve stem - to - guide clearance |
[Standard] |
Intake : 0.022 - 0.067 mm (0.00086 - 0.0026 in.) |
Exhaust : 0.05 - 0.095 mm (0.0020 - 0.0037 in.) |
[Limit] |
Intake : 0.1 mm (0.0040 in) |
Exhaust : 0.15 mm (0.0059 in.) |
