[W126 Coupe] "Whirring" noise in the engine

[Michael Ramay]

My '87 560SEL makes a "whirring" noise when it's first started. Sounds
almost like a bad bearing in the alternator and loud enough that my wife is
commenting on it but in a mile or so it goes away.

- I removed all the V-belts on the front of the motor, still have the noise.
- Since it sounds like it's coming from the passenger side of the engine up
high, I removed that valve cover then ran the engine - it was louder.
- Put in a new timing chain and new guides. !@#$%^&* - still have the noise
but the car has noticeably more power.

It REALLY needed the guides since one was broken in two and a 3" long piece
is missing plus another had the hole for the retention pin wallowed out.  I
looked very carefully down the chain pathway during the installations but no
sign of the piece.

Will removal of the oil pan allow me to see much of the lower timing chain
guide area? If the missing chain guide is jammed in there and rubbing on the
rotating bits, why would the noise diminish in a minute or so of operation?

Suggestions??

Thanks,
Mike
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