Measuring cylinder bores - RA01001201100X(01-1100)

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.

Allocation

Group no. ⁽¹⁾

Cylinder dia.

Piston dia.

Standard size 89.0 dia.

89.000 - 89.008

88.978- 88.988

89.008 - 89.016

88.988 - 88.998

89.016 - 89.024

88.998 - 89.008

1st repair size +0.35 ⁽²⁾

89.350 - 89.358

89.328 - 89.338

89.358 - 89.366

89.338 - 89.348

289.366 - 89.374

89.348 - 89.358

2nd repair size +0.7 ⁽²⁾

89.700 - 89.708

89.678 - 89.688

89.708 - 89.710

89.688 - 89.698

89.716 - 89.724

89.698 - 89.708

⁽¹⁾	The group number on new engines is stamped in the contact surface of the crankcase, next to the cylinder bore.

⁽²⁾	The group number is imprinted on the piston crown with paint and is additionally inscribed on the side next to the piston crown.

DATA

Maximum wear limit of cylinder bores in longitudinal or transverse direction at upper and lower reversal point of the 1st piston ring

0.10

MACHINING TOLERANCES

Permissible difference from cylinder shape	when new	0.013
Permissible difference from cylinder shape	wear limit	0.05
Permissible difference from rectangularity relative to cylinder height		0.05
Averaged peak-to-valley height (Rz) after polishing		0.001
Averaged peak-to-valley height (Rz) after silicone-lapping		0.001 - 0.003
Permissible waviness (Wt)		50 % of peak-to-valley height after silicone lapping

COMMERCIALLY AVAILABLE TOOLS

Internal measuring instrument for 50 - 150 mm dia. with 0.01 mm indication and measuring point pressure relief, e. g. GRM 2125	e.g.	SUNNEN Products Comp. USA-7910 Manchester St. Louis Mo. 63143
Adjusting micrometer for internal measuring instrument GRM 2125 with 50 - 200 mm setting range, e. g. SUNNEN CF-1000 M	e.g.	SUNNEN Products Comp. USA-7910 Manchester St. Louis Mo. 63143

Measuring

Use a measuring instrument with measuring point pressure relief for measuring the cylinder bores otherwise the cylinder contact surface will be scored as a result of the measuring point bearing surface and the measuring point bearing surface of the internal measuring instrument will suffer premature wear.

Set the self-centering internal measuring instrument to the cylinder dia. before measuring. Measure cylinder bore at room temperature of 22 - 24 °C.

If the measuring temperature differs, a dimensional correction must be performed.

Fig 1: Measuring Cylinder Bore

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

The amount by which the aluminum surfaces stand back (0.5 -1.5 μm) between the silicon crystals can only be measured after silicone-lapping (final state) indirectly by means of the averaged peak-to-valley height (Rz).

The specified exposed depth of the silicon crystals is obtained by the time-limited control during silicon-lapping and the result of the silicon paste used.