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DISCUSSION => Engine + Driveline => Topic started by: strad on February 25, 2008, 07:28:59 PM

Title: Blue smoke
Post by: strad on February 25, 2008, 07:28:59 PM

:(  Actually I'm not overly concerned yet.  The motor in question has 201k miles and has never been opened.  What I am noticing is blue smoke when the motor is cold - I would characterize the amount as "some," not a whole bunch but very noticeable.  This would be on accel only, not on overrun.  I just did a test session with my wife in a second car, motor fully warm, and with me driving the M42 she noticed some smoke on the first run, none after that: however, when we switched and I had her do overruns and full throttle runs, I did not see any smoke.  The motor is running 10W40 Castrol Syntec at the moment, if that makes any difference.  

What do you guys think is most likely to be on the way out?  And how much time to shop for another M42?  Or an M50 :eek:

Title: Blue smoke
Post by: tjts1 on February 25, 2008, 08:46:48 PM

If it just does it for the first few runs on start up and it passes smog I wouldn't worry about it too much. Its probably valve stem seals leaking while the engine is off. Keep track of oil consumption and drive it like you stole it.

Title: Blue smoke
Post by: 1991 E30 M42 on February 26, 2008, 08:04:28 PM

Quote from: tjts1;43584

If it just does it for the first few runs on start up and it passes smog I wouldn't worry about it too much. Its probably valve stem seals leaking while the engine is off. Keep track of oil consumption and drive it like you stole it.

It could also be piston rings, as blue smoke is a sign of burning oil. Check your compression and do a cylinder leakdown test.