[AT] Age-old question about non-detergent oil Was My 2007 Wheat Harvest

[Al Jones]

Guys,

Did a little clean up this evening to put my pull type combine "away"
until next harvest.  One question has to do with oil:  It is time to
change it, as it has the same oil in it that it had when I bought it!
The PO said he last used the combine in the late '70s so it has been at
least that long since it had an oil change. Since it's been so long, I
can't help but wonder if it has non-detergent oil in it. Now, based on
what I have heard over the years,  If I understand correctly, if you
want to switch to modern detergent oil, you can pull the engine down and
clean everything out, OR you can make the change, and change the oil and
filter several times at much shorter intervals until the gunk gets
worked loose and "flushed out."  Normally my plan would be to change the
oil, run it till it "looked dirty," and repeat this process three or
four times.  Now here's my concern:  My engine is a Continental Y-69.
It does not have an oil filter.  How will the lack of a filter change
things?  Is there a better way?  The easiest thing I know would be to
pull the valve cover and look for sludge, but the valve cover is behind
a magneto, carburetor, and several angle iron supports on the combine
and it would take a contortionist, or removing the entire engine from
the combine just to get to the valve cover!

Thanks
Al