Mm

Note.

The bearings are supplied as a set, and in replacement, always replace the bearing as a set.

Crankshaft

1. Check the crankshaft journals, crankpin journals for wear, and scores.

Also check the oil seal contact surfaces.

Check the oil holes for clogging.

2. Check the crankshaft for bend. If the bend exceeds 0.05 mm or 0.002", replace the crankshaft. To measure the bend, perform the following procedures.

Place a dial gauge onto the second or third crankshaft journal, and rotate the crankshaft slowly to read the maximum, and minimum values.

Bend equals: Max. value minus Min. value divided by two.

3. Inspect the crankpin journals for

Fig. 3-30 Measuring X4952

Crankshaft Bend

Fig. 3-30 Measuring X4952

Crankshaft Bend wear, scores , and if the eccentric or taper wear exceeds 0.03 mm (0.0012"), grind the crankpin journals, and use under-size connecting rod bearings. Refer to Connecting Rod Bearing on page 3-20.

4. Inspect the crankshaft journals for wear, scores, and eccentric or taper wear. If the wear exceeds 0.03 mm (0.0012"), grind the journals,and use under-size bearings. Refer to Crankshaft Bearings.

Crankshaft Bearing

The crankshaft bearings are also same micro finished insert type,therefore, the same procedures of inspection, and oil clearance check should be performed as the connecting rod bearings.

These bearings should never be scraped, ground or filed. Also never lap the bearing cap to obtain the proper bearing oil clearance.

1. Check the bearing for proper contact, worn thin, partially melted or heavily scored.

If necessary, replace the bearings.

2. Assemble the crankshaft, and check the crankshaft thrust clearance at the third bearing.

If the clearance exceeds 0.3 mm

(0.118"), replace the crankshaft bearings.

The specified clearance is 0.06 to 0.16 mm (0.0024 ~ 0.0065").

Fig. 3-31 Measuring Thrust V0551

?ankshaft, and arance with a

3. Assemble check the Plastigage.

The oil clearance should be 0.035 to 0.045 mm (0.0014-0.0018"), and the limit is 0 .10 mm (0. 004" ). Tightening torque of crankshaft bearing cap bolts : Front, second & third:

12.5 - 15 m-kg (90 - 108 ft-lb) Rear: 10.5 - 13 m-kg

Caution :

When assembling the bearing caps, install the same shim thickness that were removed from the bearing caps when disassembled. Never turn the crankshaft while the Plastigage is in place.

If the clearance exceeds 0.10 mm (0.004"), replace the bearings with the under-size bearings , and grind the crankshaft journals to fit the bearings.

Replacing the bearings. If a new crankshaft is to be used, always use a standard size bearings.

When the oil clearance exceeds the limit with the standard bearings, use U/S-0.05 bearings. If the oil clearance exceeds 0.10 mm (0.004" ) with U/S-0.05 bearings, grind the crankshaft journals and use U/S-0.25 bearings. The bearings are supplied as a set, and in replacement, always replace the bearings as a set.

Crankshaft journal finished diameter :

Bearing size - STD: Crankshaft journal:

Front

66.97 - 67.00 mm (2.6366 - 2.6378") 68.47 - 68.50 mm (2.6957 - 2.6969") 69.97 - 70.00 mm (2.7547 - 2.7559") 71.47 - 71.50 mm (2.8138 - 2.8150")

Bearing size - U/S-0.25: Crankshaft journal:

66.745 - 66.755 mm (2.6278 - 2.6281") 68.245 - 68.255 mm (2.6868 - 2.6872") 69.745 - 69.755 mm (2.7459 - 2.7463") 71.245 - 71.255 mm (2.8049 - 2.8053")

Bearing size -U/S-0.50: Crankshaft journal:

Fig. 3-32 Measuring Oil

66.505 - 66.515 mm (2.6183 - 2.6187") 68.005 - 68.015 mm (2.6774 - 2.6778") 69.505 - 69.515 mm (2.7364 - 2.7368") 71.005 - 71.015 mm (2.7955 - 2.7959")

Fig. 3-32 Measuring Oil

Bearing size - U/S -0.75: Crankshaft journal: Front 66.245 ~ 66.255 mm

(2.7262 ~ 2.7266") Rear 70.745 ~ 70.755 mm (2.7852 ~ 2.7856")

3. Check the camshaft journals for roundness or taper, and if it exceeds 0.05 mm (0.002"), the camshaft journals should be ground and under-size bearings should be installed.

Refer to Camshaft Bearing on page 3-24.

4. Inspect the cam lobes, and if the lift of the cam lobes are exces-

Bearing s

ize -

U/S

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