Testing compression pressure · ar0100d1200d · Mercedes-Benz WIS

AR01.00-D-1200D

Testing compression pressure

10.2.11

ENGINE 611.981 /987 in MODEL 901.6, 902.6, 903.6, 904.6

ENGINE 612.981 in MODEL 902.6, 903.6, 904.6, 905.6

ENGINE 611.983 in MODEL 690.6

D01.00-1102-06

Engine 611.981/983/987

1  Compression recorder with flexible connection piece

2  Connection piece

3  Wrench socket

D01.00-1107-06

Engine 612.981

1  Compression recorder with flexible connection piece

1.1  Angled piece

2  Connection piece

3  Wrench socket

4 Injection line (cylinder 5)

 	Remove/install
1	Bring engine to operating temperature (approx. 80 °C)	 Test compression pressure when engine is at normal operating temperature.
2	Switch off ignition
3	Connect electric cables of compression recorder (1)	Connect compression recorder (1) to battery terminal 30 and, with electrical connection set, to pin terminal 50.	AR01.10-D-0010-01D
			*001589762100
			*201589009900
4	Remove glow plugs		AR15.20-D-4111B
Danger!	Risk of accident from vehicle starting off by itself when engine running. Risk of injury from contusions and burns if you insert your hands into the engine when it is started or when it is running	Secure vehicle to prevent it moving off. Wear closed and close-fitting work clothes. Do not touch hot or rotating parts.	AS00.00-Z-0005-01A
5	Crank engine several times with contact switch (arrow) at compression recorder (1)	 To eliminate combustion residues in cylinder. Do not crank engine at the ignition/starter switch
	Inspecting
6	Use wrench socket (3) to screw connection piece (2) into the glow plug hole (arrow) of the cylinder to be inspected	 A check valve is integrated in the front of connection piece (2).	*611589046300
			*001589780900
7	Connect compression recorder (1) with flexible connection piece to connector (2) or to angled connector (1.1), respectively	 Use angled connector (1.1) only on engine 612.981 at cylinder 5. Do not damage injection line (4).
8	Test compression pressure; crank engine at least 8 revolutions with contact switch (arrow) at compression recorder (1) for this step	 Do not crank engine at ignition/starter switch
9	Carry out test procedure at the remaining cylinders in the same way
10	Compare pressures measured with the specified pressures	Installation tolerance or value when new	*BE01.00-P-1001-01A
		Wear limit or limit value	*BE01.00-P-1002-01A
		Permissible difference between individual cylinders	*BE01.00-P-1003-01A
		 If the pressure is below the minimum compression pressure or if the permissible difference between the individual cylinders is exceeded 
		Inspect cylinders for leaks	AR01.00-D-1300D
11	Install in the reverse order

Compression pressure

Number	Designation		Engine 611.981/ 983/987	Engine 612.981


BE01.00-P-1001-01A	Compression installation tolerance or new value	bar	29...35	29...35
BE01.00-P-1002-01A	Compression pressure wear limit or limit value	bar	18	18
BE01.00-P-1003-01A	Compression pressure permissible difference between individual cylinders	bar	3	3

001 589 78 09 00

Compression recorder

Wrench socket

Connection piece

Electrical connection set

611 589 04 63 00

001 589 76 21 00

201 589 00 99 00

Referenced documents

ar0100d1300d Check cylinders for leaks
ar0110d001001d Connect compression tester
ar1520d4111b Remove/install glow plugs
as0000z000501a Risk of accident from vehicle starting off by itself when engine running. Risk of injury (bruises and burns) resulting from working on the engine while it is being started or when it is running.