Checking, facing cylinder head contact surface - AR01.30-P-7162B

ENGINE 604, 605, 606 /

Cylinder head

Fig 1: Checking, Facing Cylinder Head Contact Surface

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

	Remove/Install
	Only face cylinder head contact surface if porous or damaged points are present. Minor variations of the flatness in the longitudinal direction do not need to be machined. These are evened out again when the cylinder head is tightened.
1	Remove valves		AR05.30-P-3511B
2	Prechambers removed		AR01.30-P-5402HA
3	Inspect cylinder head contact surface for flatness, porous or damaged points		*BE01.30-P-1004-02A
			*WE58.40-Z-1001-19A
4	Inspect hardness of cylinder head contact surface	If a cylinder head has been overheated, this can result in a change in the microstructure. Face-grinding only produces a leaktight bond between cylinder head-cylinder head gasket-crankcase if a certain minimum hardness is achieved	AR01.30-P-7162-02A
			*BE01.30-P-1011-02A WS03.00-P-0002C
	Test and machining dimensions for cylinder head		AR01.30-P-7162-01A
5	Measure height of cylinder head (inspection dimension H)	Note measurement obtained	*BE01.30-P-1001-02A
6	Face contact surface of cylinder head	The stock removal at the cylinder head and at the crankcase together must not be more than 0.5 mm. If the crankcase has already been refaced, the max. stock removal at the cylinder head separating surface must not exceed 0.3mm. The camshaft case must not be machined, otherwise the basic bores of the camshaft bearing are modified.	BE01.30-P-1006-02A WE58.40-Z-1001-21A
7	Once again measure height of cylinder head (inspection dimension H)	Measure stock removal.	*BE01.30-P-1001-02A
8	Rework valve seats according to stock removal at cylinder head		AR05.30-P-4511B
9	Measure distance from valve stem end to camshaft bearing base (inspection dimension T) or valve setback (inspection dimension a)	Inspection dimension (T) Insert Ø 5 mm round material into the camshaft bearing base for this purpose and measure dimension "T".	*BE01.30-P-1009-02A
		Inspection dimension (a)	*BE01.30-P-1008-02A
		Measure valve setback	AR05.30-P-4100-01A
		If the measurement obtained is less than dimension "T" or "a" no further correct valve clearance compensation exists; replace valve seat ring or cylinder head, as necessary. ↓
		replace valve seat ring	AR05.30-P-3831A
10	Install in the reverse order

Test values for cylinder head

Number	Designation			Engine 604, 605, 606
BE01.30-P-1001-02A	Height of cylinder head (H) without camshaft housing	when new	mm	126.85...127.15
		Wear limit after machining	mm	126,8
		Fig. see		AR01.30-P-7162-01A
BE01.30-P-1004-02A	Unevenness of contact surface in longitudinal direction, in transverse direction	mm		≤0.04
BE01.30-P-1006-02A	Peak-to-valley height	mm		0,006
BE01.30-P-1008-02A	Distance (a) in the case of new valves and new valve seat rings	Exhaust valve	mm	1.3...1.7
		Inlet valve	mm	1.3...1.7
		Fig. see		AR01.30-P-7162-01A
BE01.30-P-1009-02A	Distance from end of valve stem to base of camshaft bearing (T)	mm		23.7...24.2
BE01.30-P-1009-02A		Fig. see		AR01.30-P-7162-01A
BE01.30-P-1011-02A	Hardness of cylinder head contact surface in area of sealing bead of cylinder head gasket	HB		> 70
BE01.30-P-1011-02A		Fig. see		AR01.30-P-7162-01A

Fig 2: Identifying (000 589 20 21 00) Hardness Tester

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Workshop equipment

WE58.40-Z-1001-19A	Straightedge
WE58.40-Z-1001-21A	Surface grinding machine with milling fixture for light alloy surfaces