[V8] V8 Crankcase Ventilation (PT/ABH)

[Scott Justusson]

 Many hours into testing various options many years ago....  What becomes blatant IMO, is the fact that v8 oil consumption is highest at the 10qt mark on the dipstick, and it's the lowest consumption at the 8.5qt level on the dipstick.  For a sump designed for 10qts, that points directly at a PCV design fault as the cause.  In the Audi TSB, they only 'revised' the fill level to 8qt, never justified or explained it's cause.

Absolutely one of the craziest unresolved engine mysteries..  If the sump, crank and engine design was 10 quarts, and the engine burns more oil when filled correctly, that's a PCV valley-pan design problem, plain and simple.  The question really is, can it be solved by revised vacuum porting, or does it require a valley pan redesign.  IMO/E, it's most likely a combination of both.  

The irony is, the problem is likely festered by most owners *not* using synthetic oil, since losing that top couple quarts of liquid gold in under 1000miles isn't all that rewarding?  And although this is deja vu to many on these lists, GT taking a swing at it's cause and effect is a really good thing.


Scott J
92 v8 ABT Chipped

 

 

-----Original Message-----
From: Dave Saad <dsaad at icehouse.net>
To: Scott Justusson <qshipq at aol.com>
Cc: v8 <v8 at audifans.com>; CavalloGT <CavalloGT at gmail.com>
Sent: Wed, Oct 3, 2012 6:58 pm
Subject: Re: [V8] V8 Crankcase Ventilation (PT/ABH)


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