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On 14 Jul 2003 10:29:27 -0700, (basskisser) wrote:

(Steven Shelikoff) wrote in message
I'm saying that oil is being burned by an engine whenever it's running.
That for a normal engine in good shape, it's just about the only way an
engine can lose oil *if* you don't see it dripping out anywhere, either
from the case or the exhaust..

Steve
This is from an aircraft machinist's book:

Suggestions for Proper Engine Break-In

--------------------------------------------------------------------------------

Whenever an engine's piston rings are replaced whether in part or in
entirety it is necessary to break in the engine. Piston rings are
replaced at a complete engine overhaul or repair, top overhaul or
single cylinder overhaul or repair.

When we refer to engine or cylinder break in, we are talking about the
physical mating of the engine's piston rings to it's corresponding
cylinder wall. That is, we want to physically wear the new piston
rings into the cylinder wall until a compatible seal between the two
is achieved.

Proper engine break in will produce an engine that achieves maximum
power output with the least amount of oil consumption due to the fact

Notice it said LEAST amount, not none.

that the piston rings have seated properly to the cylinder wall. When
the piston rings are broken in or seated, they do not allow combustion
gases to escape the combustion chamber past the piston rings into the
crankcase section of the engine. This lack of "blow-by" keeps your
engine running cleaner and cooler by preventing hot combustion gases
and by-products from entering the crankcase section of the engine.
Excessive "blow-by" will cause the crankcase section of the engine to
become pressurized and contaminated with combustion gases, which in
turn will force normal oil vapors out of the engine's breather,
causing the engine to consume excessive amounts of oil. In addition to
sealing combustion gases in the combustion chamber, piston rings must
also manage the amount of oil present on the cylinder walls for
lubrication. If the rings do not seat properly, they cannot perform

Notice it said that the job of the rings is to manage the amount of oil
present on the cylinder walls for lubrication, not wipe all the oil away
as you have said.

this function and will allow excessive amounts of oil to accumulate on
the cylinder wall surfaces. This oil is burned each and every time the
cylinder fires. The burning of this oil, coupled with "blow-by"
induced engine breathing, are reasons that an engine that hasn't been
broken in will consume more than its share of oil.

Notice that it says if it burns excessive amounts of oil, it's
*consuming* more than it's share of oil, not that consuming no oil is
the normal case. The normal case is consuming it's share of oil, by
burning the non-excessive oil from the cylinder wall surfaces.

When a cylinder is overhauled or repaired the surface of it's walls
are honed with abrasive stones to produce a rough surface that will
help wear the piston rings in. This roughing up of the surface is
known as "cross-hatching". A cylinder wall that has been properly
"cross hatched" has a series of minute peaks and valleys cut into its
surface. The face or portion of the piston ring that interfaces with
the cross hatched cylinder wall is tapered to allow only a small
portion of the ring to contact the honed cylinder wall. When the
engine is operated, the tapered portion of the face of the piston ring
rubs against the coarse surface of the cylinder wall causing wear on
both objects. At the point where the top of the peaks produced by the
honing operation become smooth and the tapered portion of the piston
ring wears flat break in has occurred.

When the engine is operating, a force known as Break Mean Effective
Pressure or B.M.E.P is generated within the combustion chamber.
B.M.E.P. is the resultant force produced from the controlled burning
of the fuel air mixture that the engine runs on. The higher the power
setting the engine is running at, the higher the B.M.E.P. is and
conversely as the power setting is lowered the B.M.E.P. becomes less.

B.M.E.P is an important part of the break in process. When the engine
is running, B.M.E.P. is present in the cylinder behind the piston
rings and it's force pushes the piston ring outward against the coarse
honed cylinder wall. The higher the B.M.E.P, the harder the piston
ring is pushed against the wall. The surface temperature at the piston
ring face and cylinder wall interface will be greater with high
B.M.E.P. than with low B.M.E.P. This is because we are pushing the
ring harder against the rough cylinder wall surface causing high
amounts of friction and thus heat. The primary deterrent of break in
is this heat. Allowing to much heat to build up at the ring to
cylinder wall interface will cause the lubricating oil that is present
to break down and glaze the cylinder wall surface. This glaze will

Apparently there must be oil present on the cylinder wall even on a new
engine being broken in.

[rest of breakin stuff snipped since it's not relavent to oil control]

Next time, if you're going to provide a citation, you should really
think about providing one that supports your case, not one that supports
mine. Of course, you're probably sooooo stupid you didn't even
recognize who's case it supports. You probably just saw buzzwords like
"rings" and "manage the amount of oil" and assumed, like the stupid
idiot you are, that it was something which would prove your point.
Well, it did prove one thing: you don't know how to read.

Steve