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<MISC>Re: E28 525i BLUE exahust smoke! (fwd)

> Richard writes...
>
> I have a 1986 525i with 124,000 start-stop miles, I use Mobil 1 5W-50 oil=

525i. Ohhh, you're in the UK (I was wondering if it was gray market in the
States).

> I noticed as the revs passed through the 2500-1500rpm range a small cloud
> of blue smoke as emmitted from the tailpipe. 

Not a problem, really. Decceleration smoke is most always valve seal and 
guide wear in the head. Start up smoke is also the same, as oil slips by 
the seals and guides while the car sits and collects on the valves (and 
piston tops, if bad enough). Acceleration smoke is almost always bypass 
by the rings under vacuum...

Hope this helps,

Filippo

p.s. A typical "is it a big problem" metric is, if you add less than a 
quart between oil changes, it's not much of a problem, unless you're a
hardcore environmentalist...