Page 737 of 1463
1F3-8 OM600 ENGINE CONTROLS
Detach line downstream of air admission filter (13).
Vacuum drops.
Faulty thermovalve
Fit the line onto air admission filter. Built up vacuum with
vacuum pump. Detach the plug from air admission line.
Vacuum drops.
Faulty filter with restriction.
Go to test step 2. YES
NO YES NO
Page 738 of 1463
OM600 ENGINE CONTROLS 1F3-9
Test step 2
Connect vacuum pump (14) with Y adapter to PLA
vacuum unit (5). Run the engine at idle speed.
Vacuum drops to ‘0’ at approx. 30°C of the thermovalve.
Faulty thermovalve.
Defective filter with restriction.
Stop the engine. Detach the filter with restriction.
Filter with restriction is clear.
Defective filter with restriction. YESNO
YES NO
Page 739 of 1463
1F3-10 OM600 ENGINE CONTROLS
VACUUM PUMP (SECTIONAL VIEW)
2 Suction Valve
4 Piston
5 Pressure Valve
6 Safety Valve
7 O-Ring
8 Pump Housing
9 Pump Cover
12 Lever
14 Outer Return Spring
15 Inner Spring Retainer16 Roller Cam
17 Piston Rod
21 Inner Return Spring
23 Upper Spring Retainer
28 Piston Ring
30 Seal Ring
31 Oil Return Valve
32 Restrictor
SB To Brake Booster
SK To Vacuum Lines
Page 740 of 1463
OM600 ENGINE CONTROLS 1F3-11
VACUUM PUMP TEST
1 Fuel Filter
2 Vacuum Line3 Ancillaries Connection
4 Vacuum Tester
Tools Required
201 589 13 21 00 Vacuum Tester
Page 741 of 1463
1F3-12 OM600 ENGINE CONTROLS
Test Procedure
1. Remove the fuel filter (1) and keep the filter not to be
damaged from running engine.
2. Remove the vacuum line (2) from ancillaries connection (3).
3. Connect the vacuum tester (4) to the ancillaries connection
(3).
Vacuum Tester 201 589 13 21 00
4 Run the engine at idle and check vacuum pressure after 30
sec.
Notice
If out of standard, replace the vacuum pump.
5. Remove the vacuum tester.
6. Connect the vacuum line to the ancillaries connection.
7. Install the fuel filter.
Standard > 70 mbar
Page 742 of 1463
OM600 ENGINE CONTROLS 1F3-13
VACUUM PUMP
Preceding Work : Remove the poly V-belt
1 Bolt............................................................10Nm
2 Vacuum Pump
3 Vacuum Line (Ancillaries)4 Vacuum Line (Brake Booster)
5 Gasket ................................................... Replace
Page 743 of 1463
1F3-14 OM600 ENGINE CONTROLS
Removal & Installation Procedure
1. Remove the vacuum line (3, 4).
2. Remove the bolts (1) evenly.
Notice
If necessary, rotate the engine until the pressure on the
tappet of the vacuum pump is released.
3. Remove the vacuum pump (2).
4. Install the vacuum pump (2).
Tightening Torque 10 Nm
Notice
Clean the gasket residues of sealing surface of vacuum
pump and replace the gasket(5).
5. Connect the vacuum line (3, 4).
Page 744 of 1463
OM600 ENGINE CONTROLS 1F3-15
VACUUM UNIT REPLACEMENT
1 Bracket
2 Bolt
3 Vacuum Unit
4 Vacuum Line
5 Seal.............................................. Replace