[V8] V8 Crankcase Ventilation (PT/ABH)

[Ingo Rautenberg]

Hmm. Well, provided I find the time, I have three V8's with engines in them
and one engine all by its lonesome. Thought I might try to get one of the 5
speeds ready before the snow flies and work on the PCV redesign/improvement
as well...   And yes, I believe we spoke of this PCV issue four? or so
years ago also...

Ingo

On Wed, Oct 3, 2012 at 7:39 PM, Dave Saad <dsaad at icehouse.net> wrote:

> I agree (I think)
> It is beyond my skill to redesign the pcv system, but I do know about the
> 8 qt fill.
> I went so far as to cut an inch off the dipstick tube so I could run down
> below 8 qts and still see oil on the dipstick. I am happy with that.
> Replacing the rings did help a lot too. I also rebuilt the heads.
> The plugs never did look that bad before the ring job. I don't know why
> because they were swimming in oil.
> Anyway I now just accept that the motor is in good shape, and it uses oil.
> It always bugs me though that my 200K+ mile explorer has had almost
> nothing go wrong with it, and it is burning a quart about every 3000 miles
> now.
> Since the change interval is 5000 I add one qt per change. This started
> about 170k.
> On the Audi I think I might just change the filter once a year and call it
> good.
>
> Dave
>
> Sent from my iPhone
>
> On Oct 3, 2012, at 3:54 PM, Scott Justusson <qshipq at aol.com> wrote:
>
> > ....  Except one might argue that you are consuming waay too much oil?
>  If the rings are good, the valves are good, why would this be?  Er, could
> be a bad PCV system!
> >
> > I got involved in this back in the mid 90's with a customer that bought
> his 91 v8 5spd *new* and documented with Audi, dozens of complaints of oil
> consumption and visual oil plumes.  He complained so much in fact, that
> Audi bought him a brand new engine complete at 60k.  Less than 4 months
> later, the documented complaints started again.  During this time, Audi
> changed from a 10quart capacity TSB to a 8 quart fill on the v8, a TSB
> stating that 700miles to 1 quart was 'normal', and all but ignored the
> issue.  How do I know?  I reviewed every document, rebuilt his new engine
> with 30k on it, and convinced the guy that the real fix was a total
> redesign of the PCV.  And, it wasn't going to be cheap.  That got him to
> just sell the car and the 4 boxes of receipts to Ingo.
> >
> > I might also look at the 'need' to do rings much differently, that
> possibly the need is because there was too much oil in the combustion
> chamber causing hot spots resulting in premature ring blow-by.  Once I saw
> an Audiport built v8 with proper PCV ventilation, I realized this is
> probably the biggest non recall in History.  Best case, the v8 got a bad
> rap for oil blowby issues that was simply from a bad design.  VAG doesn't
> have a lot of 'good' PCV systems, dating back to the Mk1 I4 engine.  BTST.
> >
> > IMO/E this isn't conspiracy theory, this is just plain bad design of
> PCV.  I suspect a lot of the reason it was designed on the v8 engine was
> really to accommodate the sound insulation of the engine covers and fresh
> air intakes.
> >
> > I have studied PCV over the years mostly by necessity.  Long after most
> just install a catch can, I found that to be a poor and messy bandaid to a
> properly designed PCV.  And what most don't realize (esp in the turbo
> cars), that PCV airflow is matched to the engine, read:  Change the engine,
> you change the balance of PCV airflow through it.
> >
> > And some of us stare at a 1000 mile per quart consumption as nuts on a
> 8-10quart oil system with an oil thermostat and cooler.  Me especially, as
> I have installed a supercharger on my 4.5l I6 with the same oil capacity
> and 'no' cooler, and I don't go through a quart of oil in 5000miles.  How
> did I do that?  Changed the PCV design and valve to work properly.
> >
> > I'm actually thinking anyone that isn't riveted to the results GT finds,
> has becomed numbed to the problem that has been nagging these motors since
> they were built 22years ago.
> >
> > IMO, IME, and my .02
> >
> > Scott J
> > 92 v8 4.2 ABT Chipped
> >
> >
> >
> > -----Original Message-----
> > From: dsaad <dsaad at icehouse.net>
> > To: v8 <v8 at audifans.com>
> > Sent: Wed, Oct 3, 2012 3:13 pm
> > Subject: Re: [V8] V8 Crankcase Ventilation (PT/ABH)
> >
> >
> >
> > It's deja vue all over again...
> >
> > I think I wrote this exact
> > screed a few years ago!!
> > Ultimately I ended up replacing the rings -
> > which cleared (literally and figuratively) things up.
> > My car did all
> > the same things yours does - especially the cloud of blue smoke after a
> > long downhill decelleration.  In fact, the motor would die if I put
> > the clutch in after a long downhill.  I still have the problem where
> > if I park on my very steep driveway, I get a big blue cloud on
> > startup.  The rest of the time I think I am in the "normal"
> > consumption range. I havent checked it in a while but I suspect I use a
> > quart every thousand miles or so.  I think of it as a running oil
> > change :-)
> >
> > Dave
> >
> >
> > > We all know the CV
> > (crankcase ventilation) system on these engines
> > >
> > "blows"! Really, the poor design of this system literally blows
> > oil into
> > > the intake stream as it does not have good
> > separation/condensation
> > > characteristics.
> > >
> > >
> > Not a rant, just a fact.
> > >
> >
> _______________________________________________
> Audifans V8 mailing list
> Send posts to: mailto:V8 at audifans.com
> Manage your list connection: http://www.audifans.com/mailman/listinfo/v8
>
> You can help keep the audifans site running by shopping at
> http://audifans.com/shop/
>
>