Part 1
ROCKER ARMS AND CAMSHAFT
Removal
Follow removal steps outlined in illustration.
Removal Service Point
[A] Rocker Arm And Rocker Arm Shaft Removal.
1. Install the special tools to the rocker arm to hold the lash adjuster.
2. Loosen the rocker arm shaft bolts.
3. Remove the rocker arms and shaft as an assembly.
Installation
Installation in reverse order as removal.
Installation Service Points
]A[ Lash Adjuster Installation.
1. Immerse the lash adjuster in clean diesel fuel.
2. Using the special tool (air bleed wine), move the plunger up and down 4 or 5 times while pushing down lightly on the check ball in order to bleed out the air.
3. Insert the lash adjuster to rocker arm, being careful not to spill the diesel fuel. Then use the special tool to prevent the adjuster for falling while installing it.
]B[ Rocker Arm Shaft Installation.
1. Install the rocker arm shafts, place the end with notched side toward the timing belt side as shown.
]C[ Rocker Arms And Rocker Arm Shaft Installation.
1. Move the rocker arms in the directions shown in the illustration before tightening the rocker arm shaft bolts.
NOTE: Move the rocker arms until they touch the rocker arm shaft mounting bosses on the cylinder head.
]D[ Rocker Arm Spring Installation.
1. Insert the rocker arm spring at an angle to the spark plug guide and then install it so that it is at a right angle to the guide
2. Remove the special tools from rocker arms.
]E[ Oil Seal Installation.
Inspection
Camshaft
1. Measure the cam height and replace the camshaft if any height exceeds the specified limit.
Standard value:
Intake: 37.11 mm (1.46 inch)
Exhaust: 37.15 mm (1.46 inch)
Limit:
Intake: 36.61 mm (1.44 inch)
Exhaust: 36.65 mm (1.44 inch)
Lash Adjuster Leak Down Test
CAUTION:
1. The lash adjuster is a precision part. Keep it free from dust and other foreign matters.
2. Do not disassemble the lash adjusters.
3. When cleaning the lash adjusters, use clean diesel fuel only.
1. Immerse the lash adjuster in clean diesel fuel.
2. While lightly pushing down the inner steel ball using the special tool, move the plunger up and down four or five times to bleed air.
Use of the retainer facilitates the air bleeding of the rocker arm mounted type lash adjuster.
3. Remove the special tool and press the plunger. If the plunger is hard to push in, the lash adjuster is normal. If the plunger can be readily pushed in all the way, bleed the lash adjuster again and test again. If the plunger is still loose, replace the lash adjuster.
CAUTION: Upon completion of air bleeding, hold the lash adjuster upright to prevent the inside diesel fuel from spilling.
4. After air bleeding, set the lash adjuster on the special tool.
5. After the plunger has gone down somewhat 0.2 - 0.5 mm (0.008 - 0.020 inch), measure the time taken for it to go down 1 mm (0.04 inch). Replace if the measured time is out of specification.
Standard value:
4 - 20 seconds/1 mm (0.04 inch)
[Diesel fuel at 15 - 20° C (50 - 68° F)]
CYLINDER HEAD AND VALVES
Removal
Follow removal steps outlined in illustration.
Removal Service Points
[A] Cylinder Head Bolt Removal.
1. Loosen the cylinder head bolts using the special tool.
[B] Retainer Lock Removal.
1. Tag removed valves, springs and other components, noting their cylinder numbers and locations to facilitate reassembly. Store these components safely.
[C] Valve Stem Seal Removal.
Installation
Installation in reverse order as removal.
Installation Service Points
]A[ Valve Stem Seal Installation.
1. Install the valve spring seat.
2. Install a new valve stem seal using the special tool shown in the illustration.
CAUTION:
1. Do not reuse removed valve stem seals.
2. The valve stem seal must be installed using the correct special tool. Incorrect installation could result in oil leaking past the valve guide.
]B[ Valve Spring Installation.
1. Install the valve spring so that the painted end is on the rocker arm side.
]C[ Retainer Lock Installation.
1. The valve spring, if excessively compressed, causes the bottom end of retainer to be in contact with the stem seal, and damage it.
]D[ Cylinder Head Bolt Installation.
1. Before reusing the cylinder head bolt, measure that its shank length does not exceed the specified limit. Replace the bolt if this measurement exceeds the limit.
Limit: Maximum 96.4 mm (17.23 inch)
2. Fit the washer as shown.
3. Apply engine oil to the bolt thread and washer.
4. Tighten the bolts in the sequence shown until each is torqued to 74 Nm (54 ft. lbs.).
5. Loosen all bolts fully.
6. Retighten the bolts in the sequence shown until each is torqued to 20 Nm (15 ft. lbs.).
7. Make paint marks on the cylinder head bolt heads and cylinder head as shown.
8. In accordance with the tightening sequence, tighten each bolt by 90° (1/4 turn).
9. Tighten each bolt by further 90° (1/4 turn) and check that the paint marks on the bolt head and cylinder head are aligned.
CAUTION: If the bolts are tightened by an angle of less than 90° (1/4 turn), they may not hold the cylinder head with sufficient strength.
If the bolts are tightened by an angle exceeding 90°, completely remove them and repeat the installation procedure.
Inspection
Cylinder Head
1. Before cleaning the cylinder head, check it for water leaks, gas leaks, cracks, and other damage.
2. Remove all oil, water scale, sealant and carbon. After cleaning the oil passages, blow air through them to verify that they are not blocked.
3. Check the cylinder head gasket surface for flatness by using a straight edge and feeler gauge.
Standard value: 0.03 mm (0.0012 inch)
Limit: 0.2 mm (0.008 inch)
4. If flatness exceeds the specified limit, grind the gasket surface to specification.
Grinding limit: *0.2 mm (0.008 inch)
*Includes/combined with cylinder block grinding
Cylinder head height (Specification when new):
119.9 - 120.1 mm (4.720 - 4.728 inch)
Valve
1. Check the valve face for correct contact. If contact is uneven or incomplete, reface the valve seat.
2. If the margin is less than specified, replace the valve.
Standard value:
Intake: 1.0 mm (0.039 inch)
Exhaust: 1.3 mm (0.051 inch)
Limit:
Intake: 0.5 mm (0.020 inch)
Exhaust: 0.8 mm (0.031 inch)
3. Measure the valve length. If the measurement is less than specified, replace the valve.
Standard value:
Intake: 110.15 mm (4.337 inch)
Exhaust: 113.70 mm (4.476 inch)
Limit:
Intake: 109.65 mm (4.317 inch)
Exhaust: 113.20 mm (4.457 inch)
Valve Spring
1. Measure the valve spring free height. If the measurement is less than specified, replace spring.
Standard value: 50.9 mm (2.00 inch)
Limit: 49.9 mm (1.96 inch)
2. Measure the squareness of the spring. If the measurement is less than specified, replace the spring.
Standard value: 2° or less
Limit: 4°
Valve Guide
1. Measure the clearance between the valve guide and valve stem. If the clearance exceeds the specified limit, replace valve guide or valve, or both.
Standard value:
Intake: 0.02 - 0.05 mm (0.0008 - .0020 inch)
Exhaust: 0.05 - 0.09 mm (0.0020 - .0035 inch)
Limit:
Intake: 0.10 mm (0.0039 inch)
Exhaust: 0.15 mm (0.0059 inch)
Valve Seat
1. Assemble the valve, then measure the valve stem projection between the end of the valve stem and the spring seating surface. If the measurement exceeds the specified limit, replace the valve seat.
Standard value:
Intake: 49.30 mm (1.9409 inch)
Exhaust: 49.35 mm (1.9429 inch)
Limit
Intake: 49.80 mm (1.9606 inch)
Exhaust: 49.85 mm (1.9626 inch)
Valve Seat Reconditioning Procedure
1. Before correcting the valve seat, check the clearance between the valve guide and valve. If necessary, replace the valve guide.
2. Using the appropriate special tool or seat grinder, correct the valve seat to achieve the specified seat width and angle.
3. After correcting the valve seat, lap the valve and valve seat using lapping compound. Then, check the valve stem projection.
Valve Seat Replacement Procedure
1. Cut the valve seat to be replaced from the inside to reduce the wall thickness. Then, remove the valve seat.
2. Rebore the valve seat hole in the cylinder head to match the selected oversize valve seat diameter.
Intake valve seat hole diameter
0.3 O.S.: 31.80 - 31.83 mm (1.2520 - 1.2531 inch)
0.6 O.S.: 32.10 - 31.13 mm (1.2638 - 1.2650 inch)
Exhaust valve seat hole diameter
0.3 O.S.: 29.30 - 29.32 mm (1.1535 - 1.1543 inch)
0.6 O.S.: 29.60 - 29.62 mm (1.1654 - 1.1661 inch)
3. Prevent galling of the cylinder head bore by cooling the valve seat with liquid nitrogen before press-fitting it.
4. Correct the valve seat to achieve the specified width and angle.
Valve Guide Replacement Procedure
1. Using a press, push the valve guide out toward the cylinder block side.
2. Rebore the valve guide hole in the cylinder head to match the oversize valve guide that is to be fitted.
CAUTION: Do not install a valve guide of the same size again.
Valve guide hole diameters in cylinder head
0.05 O.S.: 11.05 - 11.07 mm (0.4350 - 0.4358 inch)
0.25 O.S.: 11.25 - 11.27 mm (0.4429 - 0.4337 inch)
0.50 O.S.: 11.50 - 11.52 mm (0.4528 - 0.4535 inch)
3. Press-fit the valve guide until it projects by the specified amount.
CAUTION:
1. The valve guide must be installed from the upper side of the cylinder head.
2. The valve guides differ in length on the intake and exhaust sides.
Valve Guide Length
Intake: 45.5 mm (1.791 inch)
Exhaust: 50.5 mm (1.988 inch)
4. After press-fitting the valve guide, insert a new valve and check that it slides smoothly.
OIL PUMP AND OIL PAN
Removal
Follow removal steps outlined in illustration.
Removal Service Points
[A] Oil Pan Removal.
1. Remove the oil pan mounting bole.
2. Knock the special tool between the oil pan and cylinder block as shown in the illustration.
3. Tapping the side of the special tool, slide the tool along the oil pan/cylinder block seal and thus remove the oil pan.
[B] Outer Rotor/inner Rotor Removal.
1. Make alignment dots on the outer and inner rotors for reference in reassembly.
Installation
Installation in reverse order as removal.
Installation Service Points
]A[ Inner Rotor/outer Rotor Installation.
1. Apply engine oil to the rotors. Then, install the rotors ensuring that the alignment dots made at disassembly are properly aligned.
]B[ Front Case Installation.
1. Clean the sealant application surfaces on the cylinder block and front case.
2. Apply a 3 mm (0.12 inch) diameter bead of sealant to the area shown. Be sure to install the front case within 15 minutes after applying sealant.
Specified sealant:
Mitsubishi Genuine Part No. MD970389 or equivalent.
3. Tighten the front case bolts to the specified torque.
4. After installation, wait at least one hour. Never start the engine or let engine oil touch the adhesion surface during that time.
]C[ Front Oil Seal Installation.
1. Place the special tool on the crankshaft front end and apply engine oil to the its outer diameter.
2. Apply engine oil to the oil seal lip, then push the oil seal along the guide by hand until it touches the front case. Tap the oil seal into place using the special tool.
]D[ Oil Pan Installation.
1. Clean the mating surfaces of the oil pan and cylinder block.
2. Apply a 4 mm (0.16 inch) diameter bead of sealant to the oil pan flange. Be sure to install the oil pan within 15 minutes after applying sealant.
Specified sealant:
Mitsubishi Genuine Part No. MD970389 or equivalent.
3. Tighten the oil pan bolts to the specified torque.
4. After installation, wait at least one hour. Never start the engine or let engine oil touch the adhesion surface during that time.
]E[ Drain Plug Gasket Installation.
1. Replace the drain plug gasket with a new one. Fit the new gasket as shown.
]F[ Oil Filter Installation.
1. Clean the filter mounting surfaces on the front case.
2. Apply clean engine oil to the O-ring of the oil filter.
3. Screw on the oil filter until its O-ring is seated on the mounting surface. Then, give the oil filter one further turn.
CAUTION: The oil filter must be tightened using a commercially available filter wrench. If the filter is tightened by hand only, it will be insufficiently torqued, resulting in oil leaks.
]G[ Oil Pressure Switch Installation.
1. Apply the specified sealant to the threads of the switch.
Specified sealant:
3M ATD Part No. 8660 or equivalent.
CAUTION: Use care not to allow the sealant to plug the oil passage.
Install and tighten the switch to the specified torque by using a socket wrench and torque wrench.
CAUTION: If the switch is tightened with a spanner or offset wrench, an over-torque may be applied and the switch to be damaged.
Inspection
Oil Pump
1. Fit the rotors into the front case.
2. Check the tip clearance, using a feeler gauge.
Standard value: 0.06 - 0.18 mm (0.0024 - 0.0071 inch)
3. Check the side clearance, using a straight and feeler gauge.
Standard value: 0.04 - 0.10 mm (0.0016 - 0.0039 inch)
4. Check the body clearance, using a feeler gauge.
Standard value: 0.10 - 0.18 mm (0.0039 - 0.0071 inch)
Limit: 0.35 mm (0.0138 inch)