Date: Tue, 13 Sep 2005 12:26:33 -0500
Reply-To: Stan Wilder <wilden1-1@SBCGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Stan Wilder <wilden1-1@SBCGLOBAL.NET>
Subject: Re: interesting lifter thinking?? 1.9L still a problem child
(update)
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John Rodgers, you're just singing to the choir!
I can agree about the aircraft engines (which Vanagon owner is running
one?).
We were discussing how metal might get into lifters and possibly stay there
causing problems.
I simply speculated that there is metal there in the oil pan and there is a
possibility that metal could get into the lifters and cause problems.
The oil bypasses the filter at high pressure so it doesn't make a fiddlers
damn how good your filter is.
That's the point ...........
Stan Wilder
Engine Ceramics
214-352-4931
www.engineceramics.com
----- Original Message -----
From: "John Rodgers" <inua@charter.net>
To: "Stan Wilder" <wilden1-1@sbcglobal.net>
Cc: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, September 13, 2005 10:16 AM
Subject: Re: interesting lifter thinking?? 1.9L still a problem child
(update)
> Stan,
>
> Every new engine that I had experience with ALWAYS had metal in the
> filter and/or screen and on any magnets. No matter how well measured,
> machined and fitted, the moving parts are not perfect and the parts are
> going to "wear in" to each other by rubbing off material. A closer fit
> is actually acheived this way. As you well know one will actually have
> better compression on an engine after the wearing in period (break in)
> than before the engine is ever started.
>
> The best example of this that I have ever seen was on an aircraft
> engine that had chrome plated cylinder barrels and grey iron rings
> installed. Pre-run compression was so-so, and then the engine was run on
> a test stand. The engine didn't acheive temperature and the rings
> glazed. What a mess. Low compression, high oil consumption. Oil drained,
> engine flushed and reoiled, rings were replaced, cylinders honed to
> remove any glaze, engine run at high loads with reduced cooling air,
> and the cylinder temps went way up - not overheat but at the top of the
> green on the gages, in about 20 minutes the temps began to drop, and
> then steadied about mid-temp/mid green. The engine break-in period was
> run to completion and a compression test done. Compression was right on
> for a new engine. Oil was drained through a paint strainer then flushed
> with solvent, and in the bottom of the screen was all kind of metal.
> Very fine filings, mostly ferrous, because the magnet would pick them
> up. The engine was oiled again, run again, and drained again. This time
> the oil was kept to be put back in the engine. There was no metal that
> second time.
>
> Modern filters will get metal most times. I like to cut my filters,
> flush them, and see how much metal is accumulating with each oil change.
> I also like to keep tabs on how much is ferrous, brass, and babbit. It's
> a magnet and visual thing, but it gives me some idea of the status of
> things. Over time there will be a gradual increase in the metals with
> each oil change. One more means by which to keep track as to how things
> are internally.
>
> regards,
>
> John Rodgers
> 88 GL Driver
>
> Stan Wilder wrote:
>
> >I find this dubious unless the engine is run without an oil filter.
Also,
> >the first step to a proper engine assembly procedure is to thoroughly hot
> >scrub
> >all the components which includes using tube brushes in the lifter bores.
> >George
> >---------------------------- Clip ---------------------------------
> >I've run in many rebuilt VW engines on my test stand and in every case I
had
> >a tea spoon full of metal shavings and debris in the strainer plate after
> >that first 20 minute run in at 2000 rpms.
> >I don't think this relates to getting the lifters filled with crud but
the
> >material is certainly there.
> >I've had occasion to disassemble an engine right after the run in process
> >and you'd be surprised how much wear is put on the bearings during this
> >time.
> >Much of this wear is caused by abrasive particles small enough to escape
the
> >filter process.
> >
> >Stan Wilder
> >Engine Ceramics
> >214-352-4931
> >www.engineceramics.com
> >
> >
> >
> >
>
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