One of the major reasons Detroit recommends the "old" oil has less to do
with lubricity than with soot.
A diesel engine oil needs 3 things.
Soot holding.
Lubricity.
A general additive package.
New engines have much less soot to contend with, oils suitable for them
are a poor choice for an engine that produces a lot of soot.
In the case of the 2 cycle detroit's soot is a big issue and if you look
at the TBN numbers, you will immediately see why they want you to use
one of the older oils that is forumulated for high soot. High TBN for
high soot.
There isn't a lot of magic in all this, just complexity. Frankly, I
would not use any of the oils intended for a late model engine in one of
the older engines, if I could avoid it. I would take a real careful look
at the TBN numbers for any intended oil and compare that with the
numbers from an oil that was originally recommended.
I would not use an additive package beyond about CF in an older engine,
especially if the engine was going to be run hard. I would be inclined
to use an additive package before about CH in an engine build before
about 2000, especially if it was to be run lightly.
This is about as clear as I know how to put this.
Regards,
Mike
Capt. Mike Maurice
Beaverton Oregon(Near Portland)
One of the major reasons Detroit recommends the "old" oil has less to do
with lubricity than with soot.
A diesel engine oil needs 3 things.
Soot holding.
Lubricity.
A general additive package.
New engines have much less soot to contend with, oils suitable for them
are a poor choice for an engine that produces a lot of soot.
In the case of the 2 cycle detroit's soot is a big issue and if you look
at the TBN numbers, you will immediately see why they want you to use
one of the older oils that is forumulated for high soot. High TBN for
high soot.
There isn't a lot of magic in all this, just complexity. Frankly, I
would not use any of the oils intended for a late model engine in one of
the older engines, if I could avoid it. I would take a real careful look
at the TBN numbers for any intended oil and compare that with the
numbers from an oil that was originally recommended.
I would not use an additive package beyond about CF in an older engine,
especially if the engine was going to be run hard. I would be inclined
to use an additive package before about CH in an engine build before
about 2000, especially if it was to be run lightly.
This is about as clear as I know how to put this.
Regards,
Mike
_____________________________________
Capt. Mike Maurice
Beaverton Oregon(Near Portland)
