Oily soot coming from the thru hull exhaust

[highslice]

I noticed a line of oily soot on my hull behind the port through hull, after running with the Corsa open for about 45 minutes. I had never seen this before. I thought maybe there was no water flow to that side so the exhaust was coming out hot, but when I restarted the engine and checked, there was good water flow. The engine was, and still is, running perfectly. Anybody experience this before?

It's still under warranty, so I'm not worried from that perspective, it just seems odd to me.

 

[fc3]

What is the engine's oil consumption? How many hours between adding a quart?

Best regards,
Frank

 

[highslice]

What is the engine's oil consumption? How many hours between adding a quart?

Best regards,
Frank

The engine has 25 hours since the last oil change. It needed oil for the first time since the oil change the day before I noticed the soot - it took less than 1/2 of a quart. It also burned about 1/2 quart between the 20 hour service and the last oil change at 50 hours.

 

[fc3]

Extrapolating... a quart every 50 hours sounds like a lot to me. Are you running it very hard? Are you sure the engine oil isn't overfilled? Is it blowing in via the PCV? Check the intake manifold for oil on the bottom of the plenum to see if it's from the PCV. Check the usual things despite the engine being new, compression check, leak down test, and stem seals.

 

[Nehalennia]

To me that consumption sounds slightly high and may explain your soot. Break in will always have a little oil burn, so depending on the hours you have on it now that soot present may be normal. Do you think break in was done properly? (varied speed, rpms, load and no WOT for the first 20+ hours)