Detach/Attach Special Tool For Fixing Camshaft In Place - AR05.20-P-6027-01SZ

Engine 176, 177, 178 

Engine 176, 177 

When performing all work, ensure absolute cleanliness and compliance with work procedure.

Only rotate engine in direction of engine rotation at center bolt of crankshaft using indicated box wrench.

If engine was rotated past position during setting of timings, further rotate crankshaft again by approx. 720° until correct position is reached.

If engine was rotated once opposite direction of engine rotation and/or without chain tensioner and/or without use of one of the special tools , repeat entire setting process for timings.

Engine damage right up to engine failure will otherwise occur.

1. Check size (12) on camshaft (11).

   Without this check, the incorrect special tool may be used.

   An incorrect repair right up to engine damage will otherwise occur.

   If a size of 35 mm is determined on camshaft (11), use holding device.

   If a size of 30 mm is determined on camshaft (11), use holding device in combination with holding device.

   Use of incorrect special tool will lead to an incorrect installation right up to engine damage.

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   Check size (12) of camshaft (11) with special tools from holding devices or using a 30 mm and/or 35 mm size open-end wrench.

   Special tools for size 35 mm fully included in holding device.

   Special tools for size 35 mm 

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   Put together special tools for size 30 mm from holding device and holding device. Special tools (2), (20LI), (20LO), (20RI) and (20RO) are contained in holding device and supplement with special tools (6), (13), (22L) and (22R) from holding device.

   Ensure that correct special tools are used. Engine damage right up to engine failure will otherwise occur.

   Special tools for size 30 mm 

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2. Install brackets (22L and/or 22R) from holding device and/or holding device.

   Do not rotate engine without bracket (22L and/or 22R) and/or without chain tensioner. Engine damage right up to engine failure will otherwise occur.

   Shown on left cylinder head 

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3. Attach special tools (2) from holding device and/or holding device and basic carrier (13) to cylinder head.

   For installation of special tools (2), use existing bolts of cylinder head cover.

   Tighten screws of special tools (2) alternately until special tools (2) and basic carrier (13) rest flat on sealing surface of cylinder head.

   After a correct installation, special tools (2) and basic carrier (13) must rest flat and neatly on sealing surface of cylinder head.

   Shown on left cylinder head 

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4. Install special tools (20LI, 20LO and/or 20RI, 20RO) from holding device and/or holding device.

   Observe designations on special tools (20LI, 20LO and/or 20RI, 20RO).

   Ensure that special tools (20LI, 20LO and/or 20RI, 20RO) can be slid onto hexagon without twisting.

   Install special tools (20LI, 20LO and/or 20RI, 20RO) without major force application.

   Shown on the right cylinder head 

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5. Install special tool (6) from holding device and/or holding device.

   Before disassembly of camshaft positioners (7) and/or before tightening of control valves.

   Before installation of special tool (6), release screws (6s) of special tool (6).

   If special tool (6) is correctly positioned between tooth flanks of camshaft positioners (7), tighten screws (6s) again.

   An incorrectly positioned special tool (6) will lead to an incorrect setting of the timings.

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   Special tools (20RO, 20 RI) correctly attached 

   The size of camshafts (11) and special tools (20RO, 20 RI) has the dimension 30 mm.

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   Special tool (20LO) not correctly attached 

   Special tool (20LO) with size 35 mm on camshaft (11) attached with size 30 mm.

   Courtesy of MERCEDES-BENZ USA

6. Position camshafts (11) in basic position.

   If required.

   Set basic position, is possible with respective special tool.

   Bores have been incorporated in contact surface of camshaft positioner (7) at camshaft (11).

   There are 2 different versions of camshafts (11), with 4 mm bore or with 5 mm bore.