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Ticking engines

  Excessive "Valve noise" wihle the valves are porperly set can sometimes
be attributed to "flat spots" on the cam lobes, which cause gouges in the
rocker scuff pads.
  Another more elusive sound source is "CONCAVITY" of the end of the valve stem.
As the valve clearance is set, the feeler gauge measures the distance from
the valve stem "rim' to the rocker eccentric.  In fact, the eccentric
contact the "center" of the valve stem, which may be lower than the rim,
thus the excessive clearance.
  If you suspect this of a particular valve, because of loose feel by hand,
or sound location by stethoscope, compare the rocker to cam clearance of a
"good" rocker to the "bad" one.  Too bad BMW doesn't publish the expected
cam-to-rocker clearance, but it shouldn't be too hard to figure.
  An old '02' trick in getting valve clearances back to "spec" was to use a
"VALVE-stem LASH-cap" (8mm valve stem) from an Alph Romeo, or even from
certain VW's, atop the problem valve.  This will give a flat, albeit taller
surface for the rocker to contact.  The "eta" engine has 7mm valve stems
and I've never looked for 7mm lash-caps.  I'll start asking around.
  The 8mm lash-caps are available on the aftermarket.  Get the "Hardened" ones.
Give a call if you need help installing them.

Dan Patzer
the CyberWrench from BIMMERS ONLY  206-743-2002