Check cylinders for leaks

AR01.00-P-1300MFD

Check cylinders for leaks

10.05.2019

Engine

260, 282 in model 118, 177, 247

Shown on model 177 with engine 282

1

Pressure loss tester

3

Cap

2

Cap

Shown on model 177 with engine 282

4

Center bolt

5

Crankshaft belt pulley

 Caution

Risk of injury caused by scraping or cutting body parts on sharp vehicle parts

Always wear protective gloves when working on or near sharp and non-deburred vehicle parts.
Deburr repair panels.

AS00.00-Z-0017-01A

 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

Topical note

Notes on avoiding damage through contamination and foreign objects

AH00.00-P-5000-01A



Remove

 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 burn injuries, suffocation and poisoning when working on the exhaust system and the components connected to it. Risk of suffocation and risk of poisoning caused by inhalation of gaseous and solid components of the exhaust. Risk of poisoning caused by skin contact with solid components of the exhaust.

Wear protective clothing and safety glasses. Use the extraction system. Move people out of the hazard area.

AS49.00-Z-0001-01A

1

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

 Only check cylinder leakage when the engine is at normal operating temperature.

 Warning

Risk of injury to skin and eyes suffering scalding from contact with hot coolantspray. Risk of poisoning from swallowing coolant.

Do not open cooling system unless coolant temperature is below 90 °C. Open cap slowly and release the pressure. Do not pour coolant into beverage containers.
Wear protective gloves, protective clothing and safety glasses.

AS20.00-Z-0001-01A

2

Turn cap (3) of the coolant expansion reservoir counterclockwise, release overpressure, and then unscrew cap.

3

Remove spark plugs.



Engine 260 in model 118, 177, 247

AP15.10-P-1580F



Engine 282 in model 118, 177, 247

AP15.10-P-1580I

4

Unscrew cap (2) of the filler neck.

5

Remove front section of the front right fender liner.

AR88.10-P-1301MFA



Check

6

Screw adapter into the spark plug bore of the cylinder to be checked.

 Screw-in fitting

*270589019100

7

Connect dead center locator to the adapter.

 Commercially available devices/tools
Dead center locator

 Screw-in fitting

*270589019100

8

Crank engine at center bolt (4) of crankshaft belt pulley (5) in direction of engine rotation. Position piston of cylinder to be checked by means of TDC detection device to top dead center (TDC).

 Turn engine until the ball in the inspection glass of the top dead center locator falls suddenly.

 Commercially available devices/tools
Dead center locator

9

Operate parking brake.

10

Bring transmission into park position.

11

Disconnect top dead center locator from adapter.

 Commercially available devices/tools
Dead center locator

 Screw-in fitting

*270589019100

12

Connect compressed-air hose to pressure loss tester (1).

 Pressure loss tester

*450589172100

13

Connect pressure loss tester (1) to adapter.

 Pressure loss tester

*450589172100

 Screw-in fitting

*270589019100

14

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

Cylinder leakage: permissible loss total indication

*BE01.00-P-1001-02Z

 Pressure loss tester

*450589172100

If an increased pressure loss was detected,



Determine cause.

15

Remove pressure loss tester (1) from adapter.

 Pressure loss tester

*450589172100

 Screw-in fitting

*270589019100

16

Remove adapter from the spark plug bore of the last checked cylinder.

 Screw-in fitting

*270589019100

17

Perform check process in cylinder order on remaining cylinders in same manner.



Install

18

Install front section of the front right fender liner.

AR88.10-P-1301MFA

19

Screw cap (2) onto filler neck.

20

Install spark plugs.



Engine 260 in model 118, 177, 247

AP15.10-P-1580F



Engine 282 in model 118, 177, 247

AP15.10-P-1580I

21

Tighten cap (3) of the coolant expansion reservoir.

Cylinder leakage

Number

Designation

Engine all (4xWD, CAR, smart)

BE01.00-P-1001-02Z

Cylinder leakage: permissible loss total indication

%

 25