Page 516 of 2053

1F2 -- 98 M161 ENGINE CONTROLS
D AEW OO M Y_2000
YAA1F180
14. Turn the roll over valves counterclockwise at an
angle of 90 degrees.
15. Turn the lock ring counterclockwise.
16. Remove and discard the gasket.
17. Installation should follow the removal procedure in
the reverse order.
YAA1F700
FUEL PRESSURE REGULATOR
Removal and Installation Procedure
1. Disconnect the negative battery cable.
2. Remove the fuel pressure test connector.
Installation Notice
Tightening Torque
25 NSm (18 Ib-ft)
YAA1F720
Caution: The fuel system is under pressure. To
avoid fuel spillage and the risk of personal injury or
fire, it is necessary to relieve the fuel system pres -
sure before disconnecting the fuel lines.
3. Relieve the fuel pressure in fuel supply system by
pressing the service valve.
YAA1F730
4. Disconnect the vacuum hose.
5. Disconnect the circlip and remove the fuel pressure
regulator.
6. Apply the oil to O-ring lightly and then replace it.
7. Perform a leak test of the fuel pressure regulator
with the engine off and the ignition on.
8. Installation should follow the removal procedure in
the reverse order.
Page 545 of 2053

1A3 -- 10 GENERAL ENGINE INFORMATION
D AEW OO M Y_2000
DIAGNOSIS
OIL LEAK DIAGNOSIS
Most fluid oil leaks are easily located and repaired by
visually finding the leak and replacing or repairing the
necessary parts. On some occasions a fluid leak may be
difficult to locate or repair. The following procedures may
help you in locating and repairing most leaks.
Finding the Leak
1. Identify the fluid. Determine whether it is engine oil,
automatic transmission fluid, power steering fluid,
etc.
2. Identify where the fluid is leaking from.
2.1 After running the vehicle at normal operating
temperature, park the vehicle over a large sheet
of paper.
2.2 Wait a few minutes.
2.3 You should be able to find the approximate loca-
tion of the leak by the drippings on the paper.
3. Visually check around the suspected component.
Check around all the gasket mating surfaces for
leaks. A mirror is useful for finding leaks in areas that
are hard to reach.
4. If the leak still cannot be found, it may be necessary
to clean the suspected area with a degreaser, steam
or spray solvent.
4.1 Clean the area well.
4.2 Dry the area.
4.3 Operate the vehicle for several miles at normal
operating temperature and varying speeds.
4.4 After operating the vehicle, visually check the
suspected component.
4.5 If you still cannot locate the leak, try using the
powder or black light and dye method.
Powder Method
1. Clean the suspected area.
2. Apply an aerosol-- type powder (such as foot powder)
to the suspected area.
3. Operate the vehicle under normal operating condi-
tions.
4. Visually inspect the suspected component. You
should be able to trace the leak path over the white
powder surface to the source.
Black Light and Dye Method
A dye and light kit is available for finding leaks, Refer to
the manufacturer ’s directions when using the kit.
1. Pour the specified amount of dye into the engine oil fill
tube.
2. Operate the vehicle normal operating conditions as
directed in the kit.
3. Direct the light toward the suspected area. The dyed
fluid willappear as a yellow path leading to the
source.
Repairing the Leak
Once the origin of the leak has been pinpointed and
traced back to its source, the cause of the leak must be
determined n order for it to be repaired properly. If a gas-
ket is replaced, but the sealing flange is bent, the new
gasket will not repair the leak. Thebent flange must be
repaired also. Before attempting to repair a leak, check
for the following conditions and correct them as they
may cause a leak.
Gaskets
DThe fluid level/pressure is too high.
DThe crankcase ventilation system is malfunctioning.
DThe fasteners are tightened improperly or the threads
are dirty or damaged.
DThe flanges or the sealing surface is warped.
DThere are scratches, burrs or other damage to the
sealing surface.
DThe gasket is damaged or worn.
DThere is cracking or porosity of the component.
DAn improper seal was used (where applicable).
Seals
DThe fluid level/pressure is too high.
DThe crankcase ventilation system is malfunctioning.
DThe seal bore is damaged (scratched, burred or
nicked).
DThe seal is damaged or worn.
DImproper installation is evident.
DThere are cracks in the components.
DThe shaft surface is scratched, nicked or damaged.
DA loose or worn bearing is causing excess seal wear.
Page 582 of 2053
OM600 ENGINE MECHANICAL 1B3 -- 33
D AEW OO M Y_2000
1. Remove the injection nozzle.
2. Remove the prechamber.
3. Cover the prechamber bore to avoid any chips drop-
ping into the combustion chamber.
4. Remove the protective sleeve from the countersink
and rotate the countersink into the prechamber bore
to be machined as far as the stop.
Counter Sink 601 589 00 66 00
5. Maintain size ’X’ from the top edge of mandrel to the
top edge of the sleeve with the gauge.
Height Gauge 667 589 00 23 00
6. Measure the ’X’ by using a vernier caliper.
7. Mount the turning tool onto the countersink tool and
rotate to the right approx. 5 revolutions by applying
slight pressure.
Page 605 of 2053
1B3 -- 56 OM600 ENGINE MECHANICAL
D AEW OO M Y_2000
17. Coat the camshaft with oil and install the camshaft
on the cylinder head to be TDC mark(arrow) up-
ward.
18. Measure the axial end play of the camshaft.
End Play0.06 -- 0.21mm
Notice
If out of standard, adjust it with the proper thickness
of locking washer.
19. Install the bearing caps on the camshaft according
to the number on the caps.
20. Tighten the bearing cap bolts according to the nu-
merical sequence.
Tightening Torque25 N∙m (18 lb-ft)
Notice
Tighten the No. 1 bolts(light arrow) first and then
tighten the No. 2 bolts(dark arrow) stage by stage.
OM662LA
OM661LA
Page 615 of 2053
1B3 -- 66 OM600 ENGINE MECHANICAL
D AEW OO M Y_2000
13. Remove the camshaft.
14. Remove the socket bolts(4) in the chain box.
Socket Wrench 115 589 03 07 00
15. Remove the injection pump.
Notice
See the “Removal of fuel injection pump”.
16. Remove the oil pan bolts (8, 9) in the area of the tim-
ing case cover (14).
17. Slightly loosen the remaining oil pan bolts.
18. Remove the timing case cover (19) bolts and then
remove the timing case cover (14).
Notice
Be careful not to damage the cylinder head gasket
or oil pan gasket.
Page 651 of 2053

1B3 -- 102 OM600 ENGINE MECHANICAL
D AEW OO M Y_2000
Checking
Notice
The noise which continues short time during short
travel (frequent starting of the engine) or engine
starting after a long time storage is normal operating
conditions. So, it does not need to be repaired. De-
termine the malfunctions in valve clearance com-
pensation device with noise through following tests.
If defective, replace as respectively.
1. Run the engine at more than 3000rpm for approx. 4
minutes.
2. Stop the engine. After 5minutes, check the engine
oil level and adjust if necessary.
3. Remove the cylinder head cover.
4. Check the valve tappets at TDC position of each cyl-
inders.
5. Using a drift, lightly press the valve tappet and mea-
sure clearance between the cam and valve tappet.
Notice
If the clearance exceeds 0.4mm, replace the valve
tappet.
6. If a valve tappet moves down too far in comparison
to the others, replace the valve tappet.
7. Rotate the engine and check the remaining valve
tappets.
Notice
DUnnecessary rotation of the engine will damage
the valve tappets.
DDo not rotate the engine by using the camshaft
sprocket bolt or to the opposite direction of the
engine rotation.
Page 690 of 2053
OM600 ENGINE MECHANICAL 1B3 -- 141
D AEW OO M Y_2000
4. Remove the bolt and then remove the camshaft
sprocket.
Notice
During removal, be careful not to drop the sprocket
with chain. Remove the chain carefully and then pull
out the sprocket.
5. Remove the chain tensioner.
6. Remove the camshaft bearing cap bolts according
to the removal order.
Notice
Remove the camshaft bearing cap bolts of 1(dark
arrow) first and then remove the bolts of 2 (light ar-
row) one revolution in stages until the counter -- pres-
sure is released. In order to avoid damaging the
camshaft, it is essential to adhere to the removal or-
der for the camshaft bearing caps.
OM 662LA
OM 661LA
Page 692 of 2053
OM600 ENGINE MECHANICAL 1B3 -- 143
D AEW OO M Y_2000
5. Tighten the camshaft bearing cap bolts acccording
to installation order.
Tightening Torque25 N∙m (18 lb-ft)
Notice
Tighten the No. 1 bolts (light arrow) by one revolu-
tion in stages first and then tighten the No.2 bolts
(dark arrow).
OM 662LA
OM 661LA
6. Install the camshaft sprocket to be aligned the mark-
ings of the camshaft / camshaft bearing cap (arrow).
Notice
Align the alignment marks on the timing chain and
sprocket.
7. Tighten the camshaft sprocket bolt.
Tightening Torque25 N∙m (18 lb-ft) + 90_