BTBide the

3. Connecting rod alignment.

Inspect the connecting rod for twist or bent condition using a feeler gauge, and a connecting rod aligner .

a. Remove the connecting rod bearings from the connecting rod and cap, then install the piston pin in the upper end of the connecting rod.

b. Place the connecting rod on the arbor of the aligning ficture, and tighten the connecting rod cap nuts.

c. Place the "V" block on the top of the piston pin, and slide it a-gainst the face plate. If all three points of "V" block contact the face plate, the connecting rod a-lignment is satisfactory.

d. If any of the three points on the "V" block fails to contact the face plate, and the clearancc at these points excccds more than 0.1 mm (0.004"), the connecting rod should be corrccted.

e. In such a case, correct the bend or twist until all three points on the "V" block contact the face plate properly.

e. In such a case, correct the bend or twist until all three points on the "V" block contact the face plate properly.

Fig. 3-29 Measuring Connecting

Rod for Bend W0483 &• Twist W0484

Fig. 3-29 Measuring Connecting

Rod for Bend W0483 &• Twist W0484

Connecting Rod Bearing

1. The connecting rod bearings are of the insert type, micro finished with high quality and close tolerance, and these bearings should never be scraped , ground or filed . Also never insert any shim or lap the bearing cap.

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

If necessary, replace the bearings.

3. Check the oil clearance in the following manner with a Plastigage . Clean the connecting rod bearing , and the crankpin journal.

Place the Plastigage full width of the crankpin journal, parallel to the crankshaft avoiding the oil hole of the crankpin journal. Install the connecting rod and cap, then tighten the connecting rod nuts with a torque wrench to 4.8 - 7 . 6 m-kg (35 - 55 ft-lb) torque. Never turn the connecting rod or the crankshaft.

Remove the cap taking care not to move the Plastigage. Measure the width of the compressed Plastigage at the widest point using a Plastigage scale printed on the cover. The oil clearanCc should be 0.02 to 0.06 mm (0.0008 - 0.0024"), and the limit is 0.10 mm (0 .004" ). If the clearance exceeds 0 .10 mm (0.004"), replace the bearings with the undersize bearings, and grind the crankpin journals to fit the bearings.

4. Replacing the bearings.

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

When the bearing oil clearance exceeds the limit with the standard bearings, use U/S-0.05 bearings. If the oil clearance exceeds with the. U/S-0.05 bearings, grind the crankpin journals, and use U/S-

0.25 bearings. Even after grinding the crankpin journals to the regular dimension, always check the oil clearance before installation.

Crankpin journal finished diameter: Bearing size - STD: Crankpin journal '•

Bearing size U/S-0.25 Crankpin journal:

53.74 ~ 53.75 mm (2.1157 ~ 2.1161") Bearing size U/S-0.50: Crankpin journal:

53.49 ~ 53.50 mm (2.1059 ~ 2.1063") Bearing size U/S-0.75: Crankpin journal:

53.24 ~ 53.25 mm (2.0961 - 2.0965") Bearing size U/S-1.00: Crankpin journal '■

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