Crankshaft and Cylinder Block
REMOVAL AND INSTALLATION
INSTALLATION SERVICE POINTS
]]A[[ CRANKSHAFT BEARING INSTALLATION
1. When replacing the bearings, crankshaft and/or cylinder block, read off the identification mark on the crankshaft and cylinder block (as illustrated), and select a bearing according to the following table.
2. Install bearings having an oil groove to the cylinder block.
3. Install bearings having no oil groove onto the bearing caps.
4. Install the thrust bearings at the No. 3 upper bearing with the grooved side toward the crankshaft web.
]]B[[ BEARING CAP/BEARING CAP BOLT INSTALLATION
1. Install the bearing cap so their arrow is positioned on the timing belt side.
2. When reusing the bearing cap bolt, measure that its shank length dose not exceed the specified limit. Replace the bolt if this measurement exceeds the limit.
Limit: maximum 71.1 mm (2.799 inches)
3. Apply engine oil to the bolt thread and flange of the bolt.
4. Tighten the bearing cap bolts to 25 Nm (18 ft. lbs.) torque in the sequence shown.
5. Make a paint mark on the head of each bolt.
6. Make a paint mark on the bearing cap at the position 90 degree angle to 100 degree angle from the paint mark on the bolt head in the direction of tightening the bolt.
7. Give a 90 degree angle to 100 degree angle turn to the bolt in the tightening sequence. Make sure that the paint mark on the bolt and that on the bearing cap are in alignment.
CAUTION:
^ If the bolt is turned less than 90 degree angle, proper fastening performance may not be expected. When tightening the bolt, therefore, be careful to give a sufficient turn to it.
^ If the bolt is over tightened (exceeding 100 degree angle), loosen the bolt completely and then retighten it by repeating the tightening procedure from step (1).
8. Check that the crankshaft rotates smoothly.
9. Measure the end play in the crankshaft. If the measurement exceeds the specified limit, replace the crankshaft bearings.
Standard value: 0.05 - 0.25 mm (0.0020 - 0.0098 inch)
Limit: 0.4 mm (0.016 inch)
]]C[[ REAR OIL SEAL INSTALLATION
Using special tools MD998776 and MB990938, press-fit the oil seal in the case.
]]D[[ SEALANT APPLICATION TO OIL SEAL CASE
1. Apply the sealant Mitsubishi Genuine Part number MD970389 or equivalent to the oil seal case.
2. Apply a small amount of engine oil to the entire circumference of the oil seal lip section, and place the oil seal case on the cylinder block.
]]E[[ DRIVE PLATE BOLT/FLYWHEEL BOLT INSTALLATION
1. Remove all the remaining sealant from bolts and thread holes of crankshaft.
2. Apply engine oil to the flange of bolt.
3. Apply engine oil into the thread holes of crankshaft.
4. Apply 3M(TM) AAD part number 8672 or equivalent to the drive plate bolt or flywheel bolt.
5. Tighten the bolts to specified torque.
Tightening torque: 98 ± 5 Nm (72 ± 3 ft. lbs.)
INSPECTION
CRANKSHAFT JOURNAL OIL CLEARANCE (PLASTIGAGE METHOD)
1. Remove oil from the crankshaft journal and the crankshaft bearing.
2. Install the crankshaft.
3. Cut the Plastigage to the same length as the width of 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 Plastigage at its widest part by using a scale printed on the Plastigage package.
Standard value: 0.02 - 0.04 mm (0.0008 - 0.0016 inch)
Limit: 0.1 mm (0.004 inch)
CYLINDER BLOCK
1. Visually check for cracks, rust, and corrosion, and inspect the cylinder block using a flaw detecting agent. Rectify defects where possible or replace the cylinder block.
2. Ensure that the top surface is free of gasket chips and other foreign material. Check the cylinder block top surface for distortion using a straight edge and feeler gauge.
Standard value: 0.05 mm (0.0020 inch) or less
Limit: 0.1 mm (0.004 inch)
3. If the distortion is excessive, correct within the allowable limit or replace.
Grinding limit: 0.2 mm (0.008 inch)
The total thickness of the stock allowed to be removed from cylinder block and mating cylinder head 0.2 mm (0.008 inch) at maximum.
Cylinder block height (when new): 286.7 mm (11.287 inches)
4. Check the cylinder walls for cracks and seizure marks. If defects are evident, bore all the cylinders to oversize or replace the cylinder block.
5. Using a cylinder gauge, measure each cylinder bore and cylindricity. If any cylinder is severely worn, bore all the cylinders to oversize and replace the piston and piston rings accordingly. Take measurements at the points shown.
Standard value:
Cylinder bore inside diameter: 81.5 mm (3.21 inches)
Cylindricity: 0.01 mm (0.0004 inch) or less
BORING CYLINDER
1. Oversize pistons should be based on the largest bore cylinder.
Piston size identification
NOTE: The size mark is stamped on the piston top.
2. Measure the outside diameter of piston to be used. Measure it in thrust direction as shown.
3. Based on the measured piston outside diameter (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 inch) (honing margin)
4. Bore each cylinders to the calculated boring finish dimension.
CAUTION: To prevent distortion caused by heat increased during boring, bore the cylinders in the following order: No. 2, No. 4, No. 1, No. 3.
5. Hone the cylinders to the final finish dimension (Piston O.D. + Piston-to-cylinder clearance).
6. Check the clearance between piston and cylinder.
Standard value: 0.02 - 0.04 mm (0.0008 - 0.0016 inch)
NOTE: When boring cylinders, finish all of four cylinders to the same oversize. Do not bore only one cylinder to an oversize.