Note

O Mark and record the locations of the connecting rods and their big end caps so that they can be reassembled in their original positions.

• Remove the connecting rods from the crankshaft.

Connecting Rod Installation

To minimize vibration, a pair of connecting rods (left two rods or right two) should have the same weight mark.

Big End Cap [A] Connecting Rod [B] Weight Mark, Alphabet [C] Diameter Mark [D]

• If the connecting rods, big end bearing inserts, or crankshaft are replaced with new ones, select the bearing insert and check clearance with a plastigage before assembling engine to be sure the correct bearing inserts are installed.

•Apply molybdenum disulfide grease to the upper inneT surface of the connecting rod big end.

•Apply engine oil to the inner surface of upper and lower bearing inserts.

Apply molybdenum disulfide grease [A]. Do not apply grease [B]. Oil [C].

OThe connecting rod big end is bolted using the "plastic region fastening method".

OThis method precisely achieves the needed clamping force without exceeding it unnecessarily, allowing the use of thinner, lighter bolts further decreasing connecting rod weight.

OThere are two types of the plastic region fastening. One is a bolt length measurement method and other is a tightening torque method. Observe one of the following two, but the bolt length measurement method is preferable because this is a more reliable way to tighten the big end nuts.

_ CAUTION

The connecting rod bolts are designed to stretch when tightened. Never reuse the connecting rod bolts. See the table below for correct bolt and nut usage.

(1) Bolt Length Measurement Method

• Be sure to clean the bolts, nuts, and connecting rods thoroughly with high-flash point solvent, because the new connecting rods, bolts, and nuts are treated with an anti-rust solution.

A WARNING

Clean the bolts, nuts, and connecting rods in a well-ventilated area, and take care that there is no spark or flame anywhere near the working area. This includes any appliance with a pilot light Because of the danger of highly flammable liquids, do not use gasoline or low-flash point solvents to clean them.

Immediately dry the bolts and nuts with compressed air after cleaning.

Clean and dry the bolts and nuts completely.

• Install new bolts in reused connecting rods.

• Dent both bolt head and bolt tip with a punch as shown.

• Before tightening, use a point micrometer to measure the length of new connecting rod bolts and record the values to find the bolt stretch.

Connecting Rod [A] Dent here with a punch [B]. Nuts [C]

Fit micrometer pins into dents [D]. •Tighten the big end nuts until the bolt elongation reaches the length specified in the table. •Check the length of the connecting rod bolts.

* If the stretch is more than the usable range, the bolt has stretched too much. An overelongated bolt may break in use.

Bolt Length _ Bolt Length Stretch after tightening before tightening

Connecting Rod Assy

Bolt

Nut

Usable Range of Connecting Rod Bolt Stretch

New

Use the bolts attached to new con-rod.

Attached to new con-rod

0.20 - 0.32 mm

New

Used-

Replace the bolts with new ones.

Used

0.24 - 0.36 mm

New

(2) Tightening Torque Method

*lf you don't have a point micrometer, you may tighten the nuts using the "Tightening Torque Method".

• Be sure to clean the bolts, nuts, and connecting rods thoroughly with high-flash point solvent, because the new connecting rods, bolts, and nuts are treated with an anti-rust solution.

AWARNING

Clean the bolts, nuts, and connecting rods in a well-ventilated area, and take care that there is no spark or flame anywhere near the working area. This Includes any appliance with a pilot light. Because of the danger of highly flammable liquids, do not use gasoline or low-flash point solvents to clean them.

Immediately dry the bolts and nuts with compressed air after cleaning.

Clean and dry the bolts and nuts completely.

• First, tighten the nuts to the specified torque. See the table below.

• Next tighten the nuts 120" more.

OMark [A] the connecting rod big end caps and nuts so that nuts can be turned 120° [B] properly. OTighten the hexagon nut by 2 comers.

Connecting Rod Assy

Bolt

Nut

Torque + Angle N-m (kg-m, ft-lb)

New

Use the bolts attached to new con-rod.

Attached to new con-rod

18 (1.8, 13.0) + 120°

New

20 (2.0,14.5) + 120*

Used

Replace the bolts with new ones

Used

24 (2.4.17.4) + 120*

New

25 (2.6.18.8) + 120'

CAUTION

CAUTION

Since the friction force of the seating surface and thread portion of new nuts is different from that of used ones, the nut tightening torque should be changed as specified in the above table. Be careful not to overtighten the nuts.

Connecting Rod Big End Bearing Insert/Crankpin Wear • Using a plastigage (press gauge) [A], measure the bearing insert/crankpin [B] clearance.

NOTE

0 Tighten the connecting rod big end nuts to the specified torque (see

Connecting Rod Installation). O Do not move the connecting rod and crankshaft during clearance measurement.

Connecting Rod Big End Bearing Insert/Crankpin Clearance Standard: 0.036 - 0.066 mm Service Limit 0.10 mm

*lf clearance is within the standard, no bearing replacement is required. *lf clearance is between 0.066 mm and the service limit (0.10 mm), replace the bearing inserts with inserts painted blue [C]. Check insert/crankpin clearance with the plastigage. The clearance may exceed the standard slightly, but it must not be less than the minimum in order to avoid bearing seizure. *lf the clearance exceeds the sen/ice limit, measure the diameter of the crankpins.

Crankpin Diameter

Standard: 34.984 ~ 35.000 mm Service Limit: 34.96 mm

*lf any crankpin has worn past the service limit, replace the crankshaft with a new one.

*lf the measured crankpin diameters are not less than the sen/ice limit, but do not coincide with the original diameter markings on the crankshaft, make new marks on it.

Crankpin Diameter Marks

A: Crankpin Diameter Marks, "O" mark or no mark.

• Measure the connecting rod big end bore diameter, and mark each connecting rod big end in accordance with the bore diameter.

Bore Diameter Mark (Around Weight Mark) [A]: "O" or no mark.

NOTE

O Tighten the connecting rod big end nuts to the specified torque (see

Connecting Rod Installation). O The mark already on the big end should almost coincide with the measurement.

Connecting Rod Big End Bore Diameter Marks None 38.000 ~ 38.008 mm

•Select the proper bearing insert in accordance with the combination of the connecting rod and crankshaft coding. • Install the new inserts in the connecting rod and check insert/crankpin clearance with the plastigage.

Con-rod Big End Bore Diameter' Marking

Crankpin Diameter Mark

Bearing Insert

Size Color

Part Number

None

O

Brown

92028-1714

None

None

Colorless

92028-1713

O

O

O

None

Blue

92028-1712

Crankshaft Main Bearing Insert/Journal Wear • Using a plastigage (press gauge) [A], measure the bearing insert/journal [B] clearance.

NOTE

O Tighten the crankcase bolts to the specified torque (see Crankcase Assembly).

O Do not turn the crankshaft during clearance measurement. OJournal clearance less than 0.025 mm can not be measured by plastigage, however, using genuine parts maintains the minimum standard clearance.

Crankshaft Main Bearing insert/Journal Clearance Standard: 0.020 ~ 0.044 mm Service Limit 0.07 mm

*lf clearance is within the standard, no bearing replacement is required. *lf clearance is between 0.044 mm and the service limit (0.07 mm), replace the bearing inserts with inserts painted blue [CJ. Check insert/journal clearance with the plastigage. The clearance may exceed the standard slightly, but it must not be less than the minimum in order to avoid bearing seizure. *lf clearance exceeds the service limit, measure the diameter of the crankshaft main journal.

Crankshaft Main Journal Diameter Standard: 32.984 ~ 33.000 mm Service Limit 32.96 mm

*lf any journal has worn past the service limit, replace the crankshaft with a new one.

*lf the measured journal diameters are not less than the service limit but do not coincide with the original diameter markings on the crankshaft, make new marks on it.

Crankshaft Main Journal Diameter Marks None 32.984 - 32.992 mm

□: Crankshaft Main Journal Diameter Marks, "1" mark or no mark

• Measure the main bearing bore diameter, and mark the upper crankcase half in accordance with the bore diameter. O: Crankcase Main Bearing Bore Diameter Marks, "O" mark or no mark.

NOTE

O Tighten the crankcase bolts to the specified torque (see Crankcase Assembly).

OThe mark already on the upper crankcase half should almost coincide with the measurement.

cm cm

Crankcase Main Bearing Bore Diameter Marks O 36.000 - 36.008 mm

•Select the proper bearing insert in accordance with the combination of the crankcase and crankshaft coding. • Install the new inserts in the crankcase halves and check insert/journal clearance with the plastigage.

Crankcase Main

Bearing Bore Diameter Marking

Crankshaft Main Journal Diameter Marking

Bearing Insert'

Size Color

Part Number

Journal Nos.

O

1

Brown

92028-1717

1,3, 5

92028-1720

2,4

None

1

Colorless

92028-1716

1,3, 5

O

None

92028-1719

2,4

None

None

Blue

92028 1715

1,3, 5

92028-1718

2,4

*The bearing inserts for Nos. 2 and 4 journals have an oil groove, respectively.

*The bearing inserts for Nos. 2 and 4 journals have an oil groove, respectively.

0 0

Post a comment