Check cylinders for leaks

AR01.00-P-1300MT

Check cylinders for leaks

13.12.2019

Engine

133 in model 117, 156, 176

Engine

270 in model 117, 156, 176, 242, 246.2

Modification notes

04.12.2019

Special tool 450 589 17 21 00 added.

Shown on ENGINE 270 in MODEL 246.242

01

Pressure loss tester

 Caution

Risk of injury to skin and eyes due to handling of engine oil. Risk of poisoning caused by swallowing engine oil

Wear protective gloves, protective clothing and safety glasses.
Do not fill engine oil into beverage containers.

AS18.00-Z-0001-01A

 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

 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

Determine loss of pressure at cylinder

AH01.00-N-1300-02A

 

Remove/install

1

Bring engine to operating temperature (approx. 80 °C) and switch off engine.

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

2

Switch off ignition and remove transmitter key.

3

Remove spark plugs.



Engine 133 in model 117, 156, 176

AP15.10-P-1580AHH



Engine 270 in model 117, 156, 176, 242, 246.2

AP15.10-P-1580NK

4

Slowly unscrew cap from coolant expansion reservoir.

5

Take off oil filler cap.

6

Open service flap on fender liner in right front fender.

7

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

 Crank engine at crankshaft center bolt in direction of engine rotation.

 Socket wrench bit

*001589650900

8

Connect pressure loss tester (01).

AR01.00-P-1300-01VA

 Pressure loss tester

*450589172100

 Screw-in fitting

*270589019100



Check

9

Apply compressed air to the cylinder and read off pressure loss from pressure loss tester (01).

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

 Pressure loss tester

*450589172100

If the crankshaft rotates:



Install retaining lock for crankshaft / starter ring gear.

AR03.30-P-5000NKB

10

Check other cylinders in firing order of engine.

AR01.00-P-1300-03MM

11

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