Valve Guide Specifications; Valve Stem Oil Seals - BMW 1999-2005 M3 Service Manual

Cylinder Head and Valvetrain
4 of 6
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valve guides when replacing the
guides.
BMW supplies oversize valves. See
Table d for additional information.
Table d.Valve guide specifications
Specifications
Valve guide wear,
maximum (valve
tilt clearance
measured with
new valve)
Valve guide inside
diameter, installed
(tolerance per ISO
allowance H7)
Standard
Oversize 1
Oversize 2

Valve stem oil seals

The purpose of the valve stem oil seal
is to prevent excess oil from entering
the combustion chamber. The sign of
faulty valve stem oil seals is excessive
oil consumption and smoke from the
exhaust immediately after starting and
during deceleration
Note:
Valve stem oil seals should not be
reused. If valves are removed, new
valve stem oil seals should be installed.
Valve stem oil seal replacement
requires that the cylinder head be
M52TU / M54
engine(1999 -
2001)
0.5 mm (0.020
in.)
6.0 mm (0.236
in.)
6.1 mm (0.240
in.)
6.2 mm (0.244
in.)
2/25/2009 9:48 PM