Crankshaft: Service and Repair
CRANKSHAFT, FLYWHEEL AND DRIVE PLATEREMOVAL AND INSTALLATION
Removal Steps 1-29:
INSPECTION
CRANKSHAFT OIL CLEARANCE (PLASTIC GAUGE METHOD)
1. Remove oil from the crankshaft journals and crankshaft bearings.
2. Install the crankshaft.
3. Cut the plastic gauge to the same length as the width of the bearing and place it on the journal in parallel with its axis.
4. Install the crankshaft bearing cap carefully and tighten the bolts to the specified torque.
5. Carefully remove the crankshaft bearing cap.
6. Measure the width of the plastic gauge at its widest part by using a scale printed on the plastic gauge package.
Standard value: 0.02-0.05 mm (0.0008-0.0020 in.)
Limit: 0.1 mm (0.004 in.)
CYLINDER BLOCK
1. Visually check for scratches, rust, and corrosion. Use also a flaw detecting agent for the check. If defects are evident, correct, or replace.
2. Using a straightedge and feeler gauge, check the block top surface for warpage. Make sure that the surface is free from gasket chips and other foreign matter.
Standard value: 0.05 mm (0.0020 in.)
Limit: 0.1 mm (0.004 in.)
3. If the distortion is excessive, correct within the allowable limit or replace.
Grinding limit: 0.2 mm (0.008 in.)
*Includes/combined with cylinder head grinding.
Cylinder block height (when new):
274.9-275.1 mm (10.823-10.831 in.) (4G61)
283.9-284.1 mm (11.177-11.185 in.) (4G63)
289.9-290.1 mm (11.413-11.421 in.) (4G64)
4. Check cylinder walls for scratches and seizure. If defects are evident, correct (rebore to an oversize) or replace.
5. Using a cylinder gauge, measure the cylinder bore and cylindricity. If worn badly, correct the cylinder to an oversize and replace the piston and piston rings. Measure at the points shown in illustration.
Standard value:
Cylinder l.D.
82.3 mm (3.24 in.) (4G61)
85.0 mm (3.35 in.) (4G63)
86.5 mm (3.41 in.) (4G64)
Cylindricity 0.01 mm (0.0004 in.)
BORING CYLINDER
1. Oversize pistons to be used should be determined on the basis of the largest bore cylinder.
Piston size identification
NOTE: Size mark is stamped on the piston top.
2. Measure outside diameter of piston to be used. Measure it in thrust direction as shown.
3. Based on the measured piston O.D. calculate the boring finish dimension.
Boring finish dimension = Piston O.D. + (clearance between piston O.D. and cylinder) - 0.02 mm (0.0008 in.) (honing margin)
4. Bore all cylinders to the calculated boring finish dimension.
CAUTION: To prevent distortion that may result from temperature rise during honing, bore cylinders, working from No. 2 to No.4 to No.1 to No.3.
5. Hone to final finish dimension (piston O.D. + clearance between piston O.D. and cylinder).
6. Check the clearance between piston and cylinder.
Clearance between piston and cylinder:
0.01-0.03 mm (0.0004-0.0012 in.) (4G63 SOHC)
0.03-0.05 mm (0.0012-0.0020 in.) (4G63 DOHC TIC)
0.02-0.04 mm (0.0008-0.0016 in.) (4G61, 4G63 DOHC, 4G64)
NOTE: When boring cylinders, finish all of four cylinders to the same oversize. Do not bore only one cylinder to an oversize.
INSTALLATION SERVICE POINTS
A CRANKSHAFT BEARING IDENTIFICATION
1. The upper bearings (on the cylinder block side) for Nos. 1, 2, 4 and 5 journals are provided with oil groove.
2. The lower bearings (on the cap side) for Nos. 1, 2, 4 and 5 journals are not provided with oil groove.
3. No.3 bearings are flanged and provided with no groove. Common bearings are used on the cap side and cylinder block side.
B BEARING CAP INSTALLATION
1. Check the bearing cap for the identification mark before it is installed.
2. After installing the bearing caps, make sure that the crankshaft turns smoothly and the end play is correct. If the end play exceeds the limit, replace crankshaft bearings.
Standard value: 0.05-0.18 mm (0.0020-0.0071 in.)
Limit: 0.25 mm (0.0098 in.)
C INSTALLATION SERVICE POINTS
D OIL SEPARATOR INSTALLATION
1. Force the oil separator into the oil seal case so that the oil hole in the separator is directed downward (arrow in illustration).