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Re: synthetics (long)

Sargent Schutt wrote:

> 'John Graham' wrote:
>    >Great the dirt  or varnish is on the engine not in the oil.Thats some go oil your
>    >useing. It plugs up things fast.
> I've been told by many mechanics that Valvoline 20w-50 Racing (dino) is good
> oil. According to my dealer, Hoehn Audi, it is what VAG specs for our cars. I
> change it at 3k mile intervals. So it would seem to be good oil, and good
> practice. It has taken about 20k miles to go from consumption (under synth) back to
> almost no consumption.

Let me get this right  Your useing non detergent racing oil for street use.And this is
what your dealer said to use. :-P

>    >> That the synth removes the reg oil varnish means that it is loosening up the
>    >> tolerances in the engine. More play between parts means more wear. That's
>    >>the physics.
>    >Valve gear yes, piston rings and cylinders no.Varnish has never been a good
>    >antiwear additive.
> Really? I add varnish with every other oil change. Minwax High-Gloss is best.
> But seriously, the buildup over time becomes a hardened product that, while not
> the slickest surface, whence removed allows for higher level of thrashing vis a
> vis increased (out of spec) tolerances. Imagine if I held your head in my hands,
> at the ears, and proceeded to shake it back and forth rapidly. Now imagine I held
> my hands a *couple inches from your ears* and proceeded to smack it back and
> forth rapidly. Which would you prefer? See the parallel here? Removing the
> varnish and cleaning out the gunk allows for increased thrashing. THEREFORE
> INCREASED WEAR. That's why changing over to synth on high mileage motors
> which have an amount of wear and an amount of buildup can even cause lifter
> noise, where previous to the changeover there was no noise, and no oil
> consumption.  BTDT, seen it, heard it. This isn't fiction, John.

There you go agine. Just were did I say it was fiction?I never said it was a good idea. I
fact at 140K miles one good oil change with a
good detergent dino oil may do the same thing a synthetic will.

>    >> You would seem to have it that it is better to have play in your
>    >> internal engine parts and run synth oil than it is to have no slop and no
>    >> consumption while using clean regular oil.
>    >That something you made up all on your own.
> No, it's what happens when the varnish and dino deposits are removed. Fine, I
> made it all up. There is no increased play in the internal parts. The oil is just
> magically making its way into the combustion chamber. It's all Sigfreid and Roy, pure,
> marvelous Vegas entertainment. Now please debunk this incredulous myth
> for me, if you will.
>    >> I can't agree with that. I see no logic that would support the argument that a
>    >> loose motor with synth oil consumption is a good thing compared with a
>    >>tighter
>    >> motor with no oil consumption on reg oil. I'm not arguing the proerties of
>    >> synthetics here, except in as much as I don't believe that a synthetic is good
>    >> enough to make up for the play and looseness it causes by a changeover at
>    >>high
>    >> miles.
>    >>
>    >If you can't agree with it, then why did you make it up?
>    >Know one has said anything like that.
> Why don't I agree with something I made up? Huh?. hmmm...
> Well, riddle me this:
> If my motor is consuming a quart every 3-4k miles, but has no external leaks
> and runs at normal operating temps, where has that oil gone? Is there a black
> hole in my oil pan? There's some good sci-fi.

No, in you piston rings or valve seals.

> I am using appropriate weight oil, and again, my car is running within normal
> operating temp range. Therefore it is highly doubtful that I am 'evaporating' that much
> oil from within the system (1qt pre 3-4 k miles). Rather, that oil is
> making its way into the combustion chamber through newly opened routes,
> whereupon it is burned.
> Back to the head smacking. How do you NOT have *INCREASED* wear with looser
> (way beyond spec) tolerances, particularly in the valve train, but also in the
> rings/walls and crank dept? Is synth magic?? I know of no physics which
> explain how higher, out of spec tolerances lend themselves to decreased wear
> thereafter.  No matter what type oil you use. Smack your head a few times.
> Maybe it'll come to you.

No, smack yours and learn to read

> Ahh, but it is all such fiction, eh? Fine, John, *explain* where and why my
> assertions are such pure, brazen hogwash. I did not enter into this dialogue with
> the intent of endurance-testing yet another Nomex suit. Just looking for a
> definitive explanation to this phenomenon that occurs during the changeover
> from dino to synth on high-mileage motors.  This would seem to be an important
> issue, as I and many others buy high-mileage vehicles, and, wanting to do what's best
> for them would like to know whether dino or synth is a superior choice.
> Especially given the likely wear which has already taken place under the care, or lack
> thereof, under the previous owner.
> Does the synth eventually build up its own deposits and shore up the leaks it
> caused during the changeover? Or does it continue to result in higher oil
> consumption? If the oil consumption continues, the tolerances are still loose,
> is synth superior? HOW is that possible? And how does the story end with synth
> long after the changeover (say 20k miles)? I've not stuck with it long enough to
> find out. There are a few issues here. I am hoping for a reasonable explanation of
> synth behavior after the changeover to support the contention that it is a
> superior solution to dino on high-mileage, gummed up motors, particularly
> concerning engine internals (valve train, crank case, rings/walls).
> While this thread has certainly been hashed and rehashed, I've yet to see this
> particular element (changeover effects) of it discussed to the point of
> conclusion. I will gladly take this off-line, indeed I thought I had. Seems there
> are still several people interested, though. My apologies to the rest for my
> voracious appetite for wordy BW.
> And TIA for a good *explanation*.  Certainly I have invited a fiery response here, so
> have fun.....
> Regards,
> Sarge
> 91 200q 168k miles TAP, etc
> 86 5ktq 128k miles, IA, etc

1990 CQ