Date:         Thu, 1 Jul 1999 12:30:14 -0400
Reply-To:     Martin Jagersand <jag@CS.YALE.EDU>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Martin Jagersand <jag@CS.YALE.EDU>
Subject:      Re: Trouble in Turboland. or...  drain line woe's

Perform the following simple experiment: Take a long narrow soda
straw. Fill it with a combination of air bubbles and water/Bier/soda
or whatever.

Case 1: Hold the straw above the glass.

Case 2: Submerge the bottom of the straw straw in the liquid in a glass.

In which case is the flow the best?

This experiment in mostly relevant at startup, where it takes a while
for the oil pump to biuld up pressure, and shutdown, where the
turbo will keep spinning for a while after oil pressure has gone down.

/martin
--
Westy 1.9l Turbo Diesel
Quantum 1.6l Turbo Diesel

New and used parts for sale, gas and Diesel:

    http://www.cs.yale.edu/~jag/vw/forsale.html

Martin Jagersand                 email: jag@cs.yale.edu
Computer Science Department             jag@cs.rochester.edu
Yale University

        Slow down and visit the VW diesel Westy page:
          WWW: http://www.cs.rochester.edu/u/jag/vw
-------------------------------------------------------------------

From:         Pat Dooley <pdooley@GTE.NET>
> Turbo convention demands a large, clear unobstructed flow path for the
> return oil.
> Any extra backpressure will force the return oil back into the turbo
> bearing, causing the oil to foam and significantly reduce lubrication
> quality.
>
> Every turbo charger reference you can get your hands on will tell you the
> same thing.  Keep the return line outlet well above the oil level.
>
> I can see Bulley's point, the bearing is pressurized, so you shouldn't have
> a problem.  I'm just passing on what I have read.
> I must admit I tapped the return line on my rabbit pickup to the oil pan.  I
> have approx. 30k miles on the junkyard turbo with no hint of bearing
> problems.
>
> The VW TD's I have seen also drain to the oil pan.
> However, my most other vehicles like Saab, Audi and Ford drain to a higher
> point, like on the block. - Well above the oil level.

> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com]On Behalf
> Of Bulley
> Paul-
>
> The oil return on our TD Jetta appears to be a bit lower or just
> at the oil
> level in the pan. Why are you so concerned about this? The oil coming out
> of that tube has considerable pressure/flow...It isn't like having the
> return tube submerged in oil is going to stop the gusher of oil that comes
> down that hose from making its way into the pan...why the worry?
>
> G. Matthew Bulley
> Bulley-Hewlett & Associates
> www.bulley-hewlett.com
> Cary, NC USA
> 888.468.4880 tollfree
>
>