Set Basic Position Of Camshafts - AR05.20-P-6020CD

ENGINE 651 in MODEL 166, 172, 204, 207, 212, 218, 221 

Shown on engine with belt pulley 

	Remove
1	Remove cylinder head cover trim
2	Remove cylinder head cover	Remove/install cylinder head cover	AR01.20-P-5014CD
3.1	Rotate engine at crankshaft using counterholder in direction of engine rotation and place piston for cylinder 1 at top dead center	Except code (B03) ECO start/stop function Do not rotate engine at the camshaft sprocket bolt. The engine must not be turned back. The timing chain can skip otherwise and cause engine damage. The 0° marking on belt pulley/vibration damper (1) must match with marking on cylinder crankcase (2). Counterholder	Figure
3.2	Rotate engine at crankshaft using a suitable tool in direction of engine rotation and place piston for cylinder 1 at the TDC	With code (B03) ECO start/stop function Do not rotate engine at the camshaft sprocket bolt. The engine must not be turned back. The timing chain can skip otherwise and cause engine damage. The 0° marking on belt pulley/vibration damper (1) must match with marking on cylinder crankcase (2).
4	Loosen screw/bolts (3) until the camshaft sprockets (4) can be turned on the camshafts	Screw/bolts (3) are designed with a left-hand thread.
5	Remove screw/bolts (5) and remove camshaft bearing cap (6) at both camshafts on camshaft sprocket (4)	Mark installation position of camshaft bearing cap (6) before taking off.
6	Position camshafts with hold-down tool (7)	To do this turn camshaft and mount hold-down tool (7) on the camshaft free of tension. ENGINE 651 as of 1/1/12 in MODEL 166, 172, 204, 207, 212, 218, 221 Holddown device	Fig 3
		ENGINE 651 up to 12/31/11 in MODEL 166, 172, 204, 207, 212, 218, 221 Tie-down set	Fig 2
7	Tighten screw/bolts (3) on the camshaft sprockets (4)	Screw/bolts (3) are designed with a left-hand thread. Screw/bolt, camshaft sprocket to camshaft	*BA05.20-P-1001-01N
8	Remove hold-down tool (7)	ENGINE 651 as of 1/1/12 in MODEL 166, 172, 204, 207, 212, 218, 221 Holddown device	Fig 3
		ENGINE 651 up to 12/31/11 in MODEL 166, 172, 204, 207, 212, 218, 221 Tie-down set	Fig 2
	Install
9	Mount camshaft bearing cap (6) at both camshafts on camshaft sprocket (4) and tighten down screw/bolts (5)	The camshaft bearing caps (6) are asymmetrical. Note marking when mounting. The camshafts can get damaged otherwise. Screw/bolt, camshaft bearing cap to cylinder head	*BA05.20-P-1002-01N
10	Install cylinder head cover	Remove/install cylinder head cover	AR01.20-P-5014CD
11	Install cylinder head cover trim

Fig 1: Identifying Counterholder (651 589 00 40 00)

Courtesy of MERCEDES-BENZ USA

Fig 2: Identifying Tie-Down Set (651 589 01 40 00)

Courtesy of MERCEDES-BENZ USA

Fig 3: Identifying Holddown Device (651 589 09 40 00)

Courtesy of MERCEDES-BENZ USA