Checking, machining cylinder head contact surface - RA01001204180X(01-4180)

WARNING: This page does not describe the selected car, but rather 42 other vehicles, including the 1999 Mercedes-Benz S600, 1999 Mercedes-Benz S500, 1999 Mercedes-Benz S420, 1999 Mercedes-Benz S320, and 1999 Mercedes-Benz CL600. However, it is still accessible from the selected car via links, so may be relevant.

Preceding work:

Valves removed.

Operation no. of operation texts and work units or standard texts and flat rates

Fig 1: Identifying Overall Height Of Cylinder Head

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Reference size (H)	measure and note
Cylinder head contact surface	face, pay attention to note
Sharp edges at edge of combustion chamber	deburr
Reference size (H)	once again measure, determine stock removal
Valves (42) and (43)	insert
Reference dimensions (T) between end of valve stem and base of camshaft bearing	measure; insert 6 mm dia. round bar into base of camshaft bearing as measuring aid
Valve seats	machine according to stock removal at cylinder head (05-2910)

DATA IN MM

Overall height "H" of cylinder head

135.9 - 136.0

Minimum height after machining ⁽¹⁾

135.5

Permissible difference from flatness of contact surface

longitudinally

0.08

transversally

0.0

Permissible difference in parallelism of top to bottom contact surface longitudinally

0.2

Peak-to-valley height

0.003 - 0.010

Reference dimension "T"

with camshaft bearing dia. standard size

inlet

24.21 - 24.75

with camshaft bearing dia.repair size

exhaust

22.21 - 22.75

inlet

23.96 - 24.51

exhaust

21.96 - 22.51

⁽¹⁾	The stock removal at the cylinder head and at the crankcase of an engine must together be not more than 0.4 mm (see (01-1200) ).

COMMERCIALLY AVAILABLE TOOLS

Surface grinding machine with milling device for light alloy surfaces	eg.	Sceledum, type RTY Roaro u. Fi. Schio / Italy
Knife-edge straightedge

NOTE: Machine cylinder head contact surface only if porous or damaged points exist or if an impermissible difference from the flatness in the longitudinal direction is measured.

The top cylinder head contact surface must not be machined as otherwise the bearing bores of the camshaft bearings will be altered.

If cracks are suspected (internal loss of coolant), the cylinder head must be pressure-tested.