valve guides when replacing the
guides.
BMW supplies oversize valves. See
Table d
for additional information.
Table d.Valve guide specifications
Specifications
M52TU / M54
engine(1999 -
2001)
Valve guide wear,
maximum (valve
tilt clearance
measured with
new valve)
0.5 mm (0.020
in.)
Valve guide inside
diameter, installed
(tolerance per ISO
allowance H7)
Standard
6.0 mm (0.236
in.)
Oversize 1
6.1 mm (0.240
in.)
Oversize 2
6.2 mm (0.244
in.)
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
Cylinder Head and Valvetrain
http://ebahn.bentleypublishers.com/BMW/3/E46/Repair%20Manuals/1...
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