On Sep 13, 8:34*am, jim beam <m...@privacy.net> wrote:
> this is not something i've tested, just suppose, but the oil consumption
> in my d15 engine has dropped substantially compared to when i first got
> it and after i'd fixed the leaks. *my choice of oil has meant that
> pretty much all of the gunk and deposits in the engine have dissolved
> compared to the state it /was/ in. *if this extends to the oil control
> rings, which do tend to accumulate stuff like this, maybe they're free
> to seal better, and thus reduce consumption? *if that's true, and it is
> oil rings, maybe you should stick with this engine for a while and see
> what happens as your use of mobil 1 cleans things up.

I will continue examining the breathing system and possibly replacing
parts on it. Otherwise I think the course of action above is
appropriate. Tegger has also written in the past about carbon
accumulations causing malfunctioning oil control rings, causing
increased consumption for awhile, then over time the carbon blows or
burns off, and things return to more like normal.

I am not rushing to do a compression test right away because, as you
noted Jim, and is noted elsewhere on the web, if the compression rings
are not worn, but the oil rings are, the compression will be fine and
so the test tells one nothing. Getting 42 mpg for the last six months
suggests to me compression is likely (though not definitely) good. The
tool is cheap enough and the process simple enough that I will do this
sometime for my own education, though.

Thanks for sharing your experience Jim, Leftie, Priyantha, and Tegger.
I will update if anything new arises.