Part 1

ROCKER ARMS AND CAMSHAFT






Removal
Follow removal steps outlined in illustration.

Removal Service Point





[A] Rocker Arms And Rocker Arm Shafts Removal.
Before removing rocker arms and shafts assembly, install the special tool as illustrated to prevent adjuster from dropping.

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 a special tool, 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 adjuster from falling while installing it.





]B[ Rocker Shaft Spring/Rocker Arms And Rocker Arm Shaft Installation.
1. Temporarily tighten the rocker shaft with the bolt so that all rocker arms on the inlet valve side do not push the valves.
2. Fit the rocker shaft spring from the above and position it so that it is right angles to the plug guide.

NOTE: Install the rocker shaft spring before installing the exhaust side rocker arms and rocker arm shaft.





3. Remove the special tool for securing the lash adjuster.
4. Make sure that the notch in the rocker arm shaft is in the direction as illustrated.





]C[ Camshaft Oil Seal Installation.

Inspection





Camshaft
1. Measure the cam height.

Standard Value:
Intake 37.39 mm (1.4720 inch)
Exhaust 37.47 mm (1.4752 inch)

Limit:
Intake 36.89 mm (1.4524 inch)
Exhaust 36.97 mm (1.4555 inch)

NOTE: The camshaft identification mark is stamped on the opposite end of the camshaft sprocket side.





Rocker Arm
1. Check the roller surface. If any dents, damage or seizure is evident, replace the rocker arm.
2. Check rotation of the roller. If it does not rotate smoothly or if looseness is evident, replace the rocker arm.
3. Check the inside diameter. If damage or seizure is evident, replace the rocker arm.

Lash Adjuster Leak-down Test

CAUTION:
1. The lash adjuster is a precision part. Keep it free from dust and other foreign matter.
2. Do not disassemble lash adjuster.
3. When cleaning lash adjuster, use clean diesel fuel only.





1. Immerse the lash adjuster in clean diesel fuel.
2. While lightly pushing down inner steel ball using the specie. tool, move the plunger up and down four or five times to bleed air.
Use of the special tool helps facilitate 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 lash adjuster upright to prevent inside diesel fuel from spilling.





4. After air bleeding, set lash adjuster on the special tool (Leak down tester).
5. After plunger has gone down somewhat (0.2 - 0.5 mm) , measure time taken for it to go down 1 mm. Replaced if measured time is out of specification.

Standard Value: 4 - 20 seconds /1 mm (0.04 inch)
[Diesel fuel at 15 - 20°C (59 - 68°F)]

CYLINDER HEAD AND VALVES






Removal
Follow removal steps outlined in illustration.

Removal Service Points
Precaution For Removed Parts
Keep removed parts in order according to the cylinder number and intake/exhaust.





[A] Cylinder Head Bolts Removal.
Using the special tool, loosen the cylinder head bolts. Loosen evenly, little by little.





[B] Retainer Lock Removal.
Store removed valves, springs and other parts, tagged to indicate their cylinder No. and location for reassembly.





[C] Valve Stem Seal Removal.
Do not reuse valve stem seal.

Installation
Installation in reverse order as removal.

Installation Service Points





]A[ Valve Stem Seal Installation.
1. Install the valve spring seat.
2. The special tool must be used to install the valve stem seal. Improper installation could result in oil leaking past the valve guide.

CAUTION: Do not reuse the valve stem seal.





]B[ Valve Springs Installation.
Direct the valve spring end with identification color end toward the spring retainer.





]C[ Retainer Lock Installation.
The valve spring, if excessively compressed, causes the bottom end of retainer to be in contact with, and damage, the stem seal.





]D[ Cylinder Head Gasket Identification.
Identification mark: 64





]E[ Cylinder Head Bolt Installation.
1. When installing the cylinder head bolts, check that the shank length of each bolt meets the limit. If the limit is exceeded, replace the bolt.

Limit: Max. 99.4 mm (3.91 inch)

2. Apply engine oil to the threaded portions of bolts and to the washers.





3. According to the tightening sequence, tighten the bolts to the specified torque 78 Nm (58 ft. lbs.) using the special tool (MB991654).
4. Loosen bolts completely.
5. Retighten the loosened bolts to 20 Nm (14.5 ft. lbs.) in the specified tightening sequence.
6. Make a paint mark across each bolt head and cylinder head.
7. Give a 90° turn to the bolts in the specified tightening sequence.
8. Give another 90° turn to the bolts and make sure that the paint mark on the head of each bolt and that on the cylinder head are on the same straight line.

CAUTION:
1. If the bolt is turned less than 90°, proper fastening performance may not be expected. When tightening the bolt, therefore, be careful to give a sufficient turn to it.

2. If the bolt is overtightened, loosen the bolt completely and then retighten it by repeating the tightening procedure from step (1).

Inspection





Cylinder Head
1. Check the cylinder head gasket surface for flatness by using a straightedge and thickness gauge.

Standard Value:
0.05 mm (0.0020 inch)
Limit:
0.2 mm (0.008 inch)

2. If the service limit is exceeded, correct to meet 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 - 4.73 inch)





Valve
1. Check the valve 1 ace for correct contact. If incorrect, reface using valve refacer. Valve seat contact should be maintained uniform at the center of valve face.
2. If the margin exceeds the service limit, replace the valve.

Standard Value:
Intake 1.0 mm (0.39 inch)
Exhaust 1.2 mm (0.047 inch)
Limit:
Intake 0.5 mm (0.020 inch)
Exhaust 0.7 mm (0.028 inch)





3. Measure the valve's total length. If the measurement is less than specified. replace the valve.





Valve Spring
1. Measure the free height of spring and, if it is smaller than the limit, replace.

Standard Value:
51.0 mm (2.008 inch)
Limit:
50.0 mm (1.969 inch)

2. Measure the squareness of the spring and, if the limit is exceeded, replace.

Standard Value: 2° or less
Limit: Max. 4°





Valve Guide
1. Measure the clearance between the valve guide and valve stem. If the limit is exceeded, replace the valve guide or valve, or both.

Standard Value:
Intake 0.02 - 0.05 mm (0.0008 - 0.0020 inch)
Exhaust 0.03 - 0.07 mm (0.0012 - 0.0028 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:
49.30 mm (1.9409 inch)
Limit:
49.80 mm (1.9606 inch)





Valve Seat Reconditioning Procedure
1. Before correcting the valve seat, check for clearance between the valve guide and valve and, if necessary, replace the valve guide.
2. Using the seat grinder, correct to obtain 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 form the inside to thin the wall thickness. Then, remove the valve seat.





2. Rebore the valve seat hole in the cylinder head to selected oversize valve seat diameter.

Intake seat ring hole diameters
0.3 O.S. 34.30 - 34.33 mm (1.3504 - 1.3516 inch)
0.6 O.S. 34.60 - 34.63 mm (1.3622 - 1.3634 inch)
Exhaust seat ring hole diameters
0.3 O.S. 31.80 - 31.83 mm (1.2520 - 1.2531 inch)
0.6 O.S. 32.10 - 32.13 mm (1.2638 - 1.2650 inch)

3. Before fitting the valve seat, either heat the cylinder head up to approximately 250°C (482°F) or cool the valve seat in liquid nitrogen, to prevent the cylinder head bore from galling.
4. Using a valve seat cutter, correct the valve seat to the specified width and angle.





Valve Guide Replacement Procedure
1. Using the press, remove the valve guide toward the cylinder block.
2. Re-bore the valve guide hole of the cylinder head so that it may fit to the press-fitted oversize valve guide.

CAUTION: Do not install a valve guide of the same size again.

Valve guide hole diameters
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 - 0.4437 inch)
0.50 O.S. 11.50 - 11.52 mm (0.4528 - 0.4535 inch)





3. Press-fit the valve guide until it protrude 14.0 mm (0.55 inch) from the cylinder head top surface as shown in the illustration.

NOTE:
1. When press-fitting the valve guide, work from the cylinder head top surface.
2. Pay attention to the difference in length of the valve guides. [Intake side: 45.5 mm (1.79 inch) , Exhaust side: 50.5 mm (1.99 inch)]
3. After installing the valve guides, insert new valves in them to check for sliding condition.

Cylinder Head
1. Check the cylinder head gasket surface for flatness by using a straightedge and thickness gauge.

Standard Value:
0.05 mm (0.0020 inch)
Limit:
0.2 mm (0.008 inch)

2. If the service limit is exceeded, correct to meet 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 - 4.73 inch)

Valve
1. Check the valve 1 ace for correct contact. If incorrect, reface using valve refacer. Valve seat contact should be maintained uniform at the center of valve face.
2. If the margin exceeds the service limit, replace the valve.

Standard Value:
Intake 1.0 ram (0.39 inch)
Exhaust 1.2 mm (0.047 inch)
Limit:
Intake 0.5 ram (0.020 inch)
Exhaust 0.7 mm (0.028 inch)

3. Measure the valve's total length. If the measurement is less than specified. replace the valve.

Valve Spring
1. Measure the free height of spring and, if it is smaller than the limit, replace.

Standard Value:
51.0 mm (2.008 inch)
Limit:
50.0 mm (1.969 inch)

2. Measure the squareness of the spring and, if the limit is exceeded, replace.

Standard Value: 2° or less
Limit: Max. 4°

Valve Guide
1. Measure the clearance between the valve guide and valve stem. If the limit is exceeded, replace the valve guide or valve, or both.

Standard Value:
Intake 0.02 - 0.05 mm (0.0008 - 0.0020 inch)
Exhaust 0.03 - 0.07 mm (0.0012 - 0.0028 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:
49.30 mm (1.9409 inch)
Limit:
49.80 mm (1.9606 inch)

Valve Seat Reconditioning Procedure
1. Before correcting the valve seat, check for clearance between the valve guide and valve and, if necessary, replace the valve guide.
2. Using the seat grinder, correct to obtain 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 form the inside to thin the wall thickness. Then, remove the valve seat.
2. Rebore the valve seat hole in the cylinder head to selected oversize valve seat diameter.

Intake seat ring hole diameters
0.3 O.S. 34.30 - 34.33 mm (1.3504 - 1.3516 inch)
0.6 O.S. 34.60 - 34.63 mm (1.3622 - 1.3634 inch)
Exhaust seat ring hole diameters
0.3 O.S. 31.80 - 31.83 mm (1.2520 - 1.2531 inch)
0.6 O.S. 32.10 - 32.13 mm (1.2638 - 1.2650 inch)

3. Before fitting the valve seat, either heat the cylinder head up to approximately 250°C (482°F) or cool the valve seat in liquid nitrogen, to prevent the cylinder head bore from galling.
4. Using a valve seat cutter, correct the valve seat to the specified width and angle.

Valve Guide Replacement Procedure
1. Using the press, remove the valve guide toward the cylinder block.
2. Re-bore the valve guide hole of the cylinder head so that it may fit to the press-fitted oversize valve guide.

CAUTION: Do not install a valve guide of the same size again.

Valve guide hole diameters
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 - 0.4437 inch)
0.50 O.S. 11.50 - 11.52 mm (0.4528 - 0.4535 inch)

3. Press-fit the valve guide until it protrude 14.0 mm (0.55 inch) from the cylinder head top surface as shown in the illustration.

NOTE:
1. When press-fitting the valve guide, work from the cylinder head top surface.
2. Pay attention to the difference in length of the valve guides. [Intake side: 45.5 mm (1.79 inch) , Exhaust side: 50.5 mm (1.99 inch) ]
3. After installing the valve guides, insert new valves in them to check for sliding condition.

FRONT CASE, COUNTERBALANCE SHAFT AND OIL PAN






Removal
Follow removal steps outlined in illustration.

Removal Service Points





[A] Oil Pan Removal.
1. Remove all oil pan bolts.
2. Drive in the special tool between the cylinder block and oil pan.

NOTE: Never use a screwdriver or chisel, instead of the service tool, as a deformed oil pan flange will result in oil leakage.





[B] Plug Removal.
If the plug is too tight, hit the plug head with a hammer two to three times, and the plug will be easily loosened.








[C] Flange Bolt Removal.
1. Remove the plug on the side of cylinder block.
2. Insert a Phillips screwdriver [shank diameter 8 mm (0.32 inch)] into the plug hole to lock the counterbalance shaft.





3. Loosen the flange bolt.





[D] Counterbalance Shaft Front Bearing Removal.
Using the special tool, remove the counterbalance shaft front bearing from the cylinder block.

NOTE: Be sure to remove the front bearing first.
If it has not been removed, the Rear Bearing Puller cannot be used.





[E] Counterbalance Shaft Rear Bearing Removal.
Using the special tool, remove the left counterbalance shaft rear bearing from the cylinder block.

NOTE: When removing the left counterbalance shaft rear bearing, install the special tool (MB991603) in front of the cylinder block.

Installation
Installation in reverse order as removal.

Installation Service Points





]A[ Right Counterbalance Shaft Rear Bearing Installation.
1. Apply engine oil to the outer surface of bearing.
2. Using special tools, install right rear bearing. Make sure that oil hole of bearing is aligned with oil hole of cylinder block.





]B[ Left Counterbalance Shaft Rear Bearing Installation.
1. Install the special tool (GUIDE PLATE) tool to the cylinder block.
2. Apply engine oil to the rear bearing outer circumference and bearing hole in cylinder block.





3. Using the special tool, install the rear bearing.

NOTE: The left rear bearing has no oil holes.





]C[ Counterbalance Shaft Front Bearing Installation.
Using special tools, install front bearing.





]D[ Front Case Installation.
1. Set the special tool on the front end of crankshaft and apply a thin coat of engine oil to the outer circumference of the special tool to install the front case.





2. Install the front case assembly through a new front case gasket and temporarily tighten the flange bolts (other than those for tightening the filter bracket).





]E[ Counterbalance Shaft Oil Seal Installation.





]F[ Oil Pump Oil Seal Installation.





]G[ Crankshaft Front Oil Seal Installation.
Using the special tool, install the crankshaft front oil seal into the front case.





]H[ Oil Pump Driven Gear / Oil Pump Drive Gear Installation.
Apply engine oil amply to the gears and line up the alignments marks.