Rocker Arms and Camshaft

REMOVAL AND INSTALLATION

Removal Service Points
[A] Lash Adjuster Removal

CAUTION: If the lash adjuster is re-used, clean the lash adjuster.

Installation Service Points
]A[ Lash Adjuster Installation

CAUTION: If the lash adjuster is re-used, clean the lash adjuster.

1. Fit the lash adjuster onto the rocker arm without allowing diesel fuel to spill out.

]B[ Camshaft Installation
1. Apply engine oil to journals and cams of the camshafts.





2. Install the camshafts on the cylinder head. Use care not to confuse the intake camshaft with the exhaust one. The intake camshaft has a slit on its rear end for driving the crankshaft position sensor.
3. Install the crankshaft sprocket B or spacer and flange to an end of the crankshaft, and turn the crankshaft until the timing marks are lined up, setting No. 1 cylinder to the TDC.





4. Place the camshafts so that their dowel pins are positioned at top.

]C[ Bearing Caps Installation





1. According to the identification mark stamped on top of each bearing cap, install the caps to the cylinder head. Only "L" or "R" is stamped on No. 1 bearing cap. Cap No. is stamped on No. 2 to No. 5 bearing caps. Rear bearing cap has no stamping.
I: For intake camshaft side
E: For exhaust camshaft side





2. Tighten the bearing caps in the order shown two to three times by torquing progressively. Tighten to specification in the final sequence.
3. Check to ensure that the rocker arm is held in position on the lash adjuster and valve stem end.





]D[ Camshaft Oil Seal Circular Packing Installation

INSPECTION

Camshaft








1. Measure the cam height.

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 Adjusters

CAUTION:
1. The lash adjusters are precision-engineered mechanisms. Do not allow them to become contaminated by dirt or other foreign substances.
2. Do not attempt to disassemble the lash adjusters.
3. Use only fresh diesel fuel to clean the lash adjusters.





1. Prepare three containers and approximately five liters of diesel fuel. Into each container, pour enough diesel fuel to completely cover a lash adjuster when it is standing upright. Then, perform the following steps with each lash adjuster.
2. Place the lash adjuster in container A and clean its outside surface.





NOTE: Use a nylon brush if deposits are hard to remove.





3. While gently pushing down the internal steel ball using special tool MD998442, move the plunger through 5 to 10 strokes until it slides smoothly. In addition to eliminating stiffness in the plunger, this operation will remove dirty oil.

CAUTION: The steel ball spring is extremely weak, so the lash adjuster's functionality may be lost if the air bleed wire is pushed in hard.

NOTE: If the plunger remains stiff or the mechanism appears otherwise abnormal, replace the lash adjuster.





4. Remove the lash adjuster from the container. Then, push down the steel ball gently and push the plunger to eliminate diesel fuel from the pressure chamber.

CAUTION: Make sure the oil hole in the side of the body is pointing toward container A. Do not point the oil hole at yourself or other people.





5. Place the lash adjuster in container B. Then, gently push down the internal steel ball using special tool MD998442 and move the plunger through 5 to 10 strokes until it slides smoothly. This operation will clean the lash adjuster's pressure chamber.

CAUTION: The steel ball spring is extremely weak, so the lash adjuster's functionality may be lost if the air bleed wire is pushed in hard.





6. Remove the lash adjuster from the container. Then, push down the steel ball gently and push the plunger to eliminate diesel fuel from the pressure chamber.

CAUTION: Make sure the oil hole in the side of the body is pointing toward container A. Do not point the oil hole et yourself or other people.





7. Place the lash adjuster in container C. Then, gently push down the internal steel ball using special tool MD998442.

CAUTION: Do not use container C for cleaning. If cleaning is performed in container C, foreign matter could enter the pressure chamber when the chamber is filled with diesel fuel.





8. Stand the lash adjuster with its plunger at the top, then push the plunger downward firmly until it moves through its greatest possible stroke. Return the plunger slowly, then release the steel ball and allow the pressure chamber to fill with diesel fuel.





9. Remove the lash adjuster from the container, then stand the lash adjuster with its plunger at the top. Push the plunger firmly and check that it does not move. Also, check that the lash adjuster's height matches that of a new lash adjuster.

NOTE: If lash adjuster contracts, perform the operations 7 through 9 again to fill it with diesel fuel completely. Replace the lash adjuster if it still contracts after performing these steps.





10. Set the lash adjuster on the special tool MD998440 (leak down tester).





11. Remove the bolt from the tester, then adjust the height as illustrated.
12. After the plunger has moved downward slightly [0.2 to 0.5 mm (0.008 - 0.019 inch)], measure the time taken for it to move downward by a further 1 mm (0.04 inch).
Standard value: 3 - 20 seconds/1 mm(0.04 inch) [with diesel fuel at 15 to 20°C (59 - 68°F)]

NOTE: Replace the lash adjuster if the time measurement is out of specification.





13. Place the lash adjuster in container C again, then gently push down the internal steel ball using special tool MD998442.
14. Stand the lash adjuster with its plunger at the top, then push the plunger downward firmly until it moves through its greatest possible stroke. Return the plunger slowly, then release the steel ball and allow the pressure chamber to fill with diesel fuel.





15. Remove the lash adjuster from the container, then stand the lash adjuster with its plunger at the top. Push the plunger firmly and check that it does not move. Also, check that the lash adjuster's height matches that of a new lash adjuster.

NOTE: If lash adjuster contracts, perform the operations 13 through 15 again to fill it with diesel fuel completely. Replace the lash adjuster if it still contracts after performing these steps.

16. Stand the lash adjuster upright to prevent diesel fuel spilling out. Do not allow the lash adjuster to become contaminated by dirt or other foreign matter. Fit the lash adjuster onto the engine as soon as possible.