drain plugs and timing chains

["Watry, Andrew (LNG-SFR)" <Andrew.Watry@xxxxxxxxxxxxxx>]

I thought I was doing a simple oil change on my 1973 2000 Berlina on
Saturday until I unscrewed the oil drain plug and found six half-round
pieces of timing chain roller stuck to its magnet.  Taking off the cam cover
and looking in from the top, I could see the missing rollers were all from
the lower chain, not the upper chain.  So that car's not going anywhere for
awhile.  You can't easily change the lower chain, so I'll probably swap in
another engine I have rather than tear down this one.  Sigh.  I had this car
on the track at Sears Point last month, and don't like to think about what
that chain might have been doing to the sprockets, or what would have
happened if it had broken.

My other Berlina, on replacing its head gasket in January, had three missing
rollers on the upper chain.  And I have just driven it 900 miles at freeway
speed.

In 26 years of Alfa ownership, I've never seen timing chain problems before,
and never ever found anything on the drain plug magnet other than the
typical mud-like sludge.  

Moral?  Look at your timing chains closely from time to time.  And it pays
to do your own oil changes (or have an experienced Alfa shop do them), and
examine what comes out of the engine.  Oil analysis on engines you
particularly care about or that are really expensive can be a good idea too.
It's common for aircraft engines.

Andrew Watry
Berlina Register
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