Beautiful.
--- Daniel1312@aol.com wrote:
> The oil pressure is governed by both the power of
> the oil pump which
> increases with rpm being driven at half engine speed
> and the bearing
> clearances (I think). As the bearings wear the
> clearances increases and
> pressure drops.
>
> Yes, there comes a point when too much oil pressure
> is not only required but
> can be a bad thing (Lotus 1585 twin cam never liked
> a lot of pressure).
>
> However, too low a pressure, especially when the
> engine temperatures are
> high, can result in a break down of the oil film -
> resulting in damage. With
> low oil pressure (I think) the film can break down
> more easily. A higher
> viscosity oil will break down (the film) less easily
> at high temperatures but
> can make the pump work harder when the oil is cold
> because the oil is
> thicker. A thing about multigrade oils is that the
> two numbers refer to
> respective viscosity at different temperatures - I
> think that is the
> simpliest summary I can manager without running to
> 2,000 words. Here is the
> advantage of the 5/50 and 15/50 Mobil 1 synthetic
> as oppose a 20/50 which is
> actually thicker at a cold temperature while not
> getting any thinner at the
> top end (50). A synthetic also does not break down
> at very high
> temperatures, as found in turbocharger centre
> bearings and extreme operating
> conditions (maybe low oil pressure and high engine
> temperature). I don't
> think STP does any harm to an engine with low oil
> pressure unless it increase
> the viscosity at extreme low temperatures (like in
> the Artic circle?). Some
> additives, not sure about STP contain additives that
> do more than just
> increase viscosity and protect bearings when the oil
> film either breaks down
> (ZDDP?) or prevent the break down (Teflon?).
>
>
> Daniel1312 - who has seen an engine with STP almost
> go off the gauge on a
> cold start!
>
>
> In a message dated 23/10/99 19:23:01 GMT Daylight
> Time, jboatri@emory.edu
> writes:
>
> << Any thoughts? >>
>
=====
Ron Soave
"You Are What You Remember"
1960 Bugeye
1972 BGT
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