Check Cylinders For Leaks - AR01.00-P-1300MFG

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Engine 139 in model 118, 177, 247

Courtesy of MERCEDES-BENZ USA

	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
	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 overpressure. Do not pour coolant into beverage containers. Wear protective gloves, protective clothing and safety glasses.	AS20.00-Z-0001-01A
	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
	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
Notice	Notes on avoiding damage through contamination and foreign objects		AH00.00-P-5000-01A
	Remove/install
1	Warm up Engine to normal operating temperature.
2	Switch off ignition and store transmitter key outside of transmitter range (min. 2 m).
3	Remove spark plugs.
		Only install upper Engine cover after the leak test.	AP15.10-P-1580J
4	Unscrew cap of coolant expansion reservoir.
5	Unscrew oil filler cap.
6	Remove front section of the front right fender liner.		AR88.10-P-1301MFA
7	Turn Engine at belt pulley of crankshaft in direction of Engine rotation until piston of cylinder to be checked is at top dead center (ignition TDC).	Do not turn Engine opposite direction of Engine rotation. Otherwise, the timing chain will jump and Engine damage will occur. Counterholder	Fig 3
8	Connect pressure loss tester (1) with adapter to spark plug bore of cylinder to be checked.		AR01.00-P-1300-01MFG
		Pressure loss tester	Fig 2
		Adapter	Fig 1
	Check
9	Apply compressed air to the cylinder and read off pressure loss from pressure loss tester (1). Determine loss of pressure at cylinder		AH01.00-P-1300-02KOA
		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 If the crankshaft rotates: ↓	*BE01.00-P-1003-02Z
		Install retaining lock for crankshaft on belt side.	AR03.30-P-0004MFG
10	Check other cylinders in firing order of Engine.		AR01.00-P-1300-03MM
11	Install in the reverse order.
12	Carry out Engine test run and check Engine for proper leak tightness and leak tightness.
13	Install upper Engine cover.
			AP01.10-P-2405-01K