Check cylinders for leaks

AR01.00-P-1300MFF

Check cylinders for leaks

03.04.2019

Engine

654 in model 118, 177, 247

1

Pressure loss tester

 Warning

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.

Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.

AS00.00-Z-0005-01A

 Warning

Risk of injury. Skin or eye injuries may result when handling hot or glowing objects.

Wear protective gloves, protective clothing and safety glasses, if necessary.

AS00.00-Z-0002-01A

 Warning

Risk of injury. Moving parts can pinch, crush or, in extreme cases even sever extremities.

No parts of the body or limbs should be within the operating area of mechanical components when moving components.

AS00.00-Z-0009-01A

Topical note

Notes on avoiding damage through contamination and foreign objects

AH00.00-P-5000-01A

 

Remove/install

1

Warm up engine to normal operating temperature and switch off engine.

2

Remove glow plugs.

AR15.20-P-4111MFF

3

Remove front section of the fender liner in the front right fender.

AR88.10-P-1301MFA

4

Position piston of cylinder to be checked at top dead center (ignition TDC) using counterholder.


Engine must not be cranked back.
The timing chain can skip otherwise and cause engine damage.

 Turn engine at belt pulley/vibration damper in direction of engine rotation.

 Counterholder

*654589004000

5

Connect pressure loss tester (1) to glow plug holes.

AR01.00-P-1300-01MFF

  Use a screw-in piece without check valve.

 Pressure loss tester

*450589172100

 Screw-in fitting

*642589026300



Check

6

Apply compressed air to the cylinder and read off pressure loss at pressure loss tester (1).

Determine loss of pressure at cylinder

AH01.00-N-1300-02A

Cylinder leakage: permissible loss total indication

*BE01.00-P-1001-02Z

Cylinder leaktightness: Permissible losses at valves and cylinder head gasket

*BE01.00-P-1002-02Z

Cylinder leaktightness: Permissible losses at pistons and piston rings

*BE01.00-P-1003-02Z

If increased pressure loss exists



Determine cause.

7

Perform check of additional cylinders in engine firing order.

AR01.00-P-1300-03T

8

Install in the reverse order.

Cylinder leakage

Number

Designation

Engine all (4xWD, CAR, smart)

BE01.00-P-1001-02Z

Cylinder leakage: permissible loss total indication

%

 25

Cylinder leakage

Number

Designation

Engine all (4xWD, CAR, smart)

BE01.00-P-1002-02Z

Cylinder leaktightness: Permissible losses at valves and cylinder head gasket

%

 10

Cylinder leakage

Number

Designation

Engine all (4xWD, CAR, smart)

BE01.00-P-1003-02Z

Cylinder leaktightness: Permissible losses at pistons and piston rings

%

 20