Date: Sun, 8 Aug 2004 17:00:53 -0700
Reply-To: Tom Young <tomyoung1@COMCAST.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Tom Young <tomyoung1@COMCAST.NET>
Subject: Re: Noisy lifters, rockers, at startup, etc (long)
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John:
You're at the point of rebuilding that engine, pure and simple. The pieces
inside the lifters are closely machined; eventually they just wear out and
won't hold oil after shutdown, no matter what. MMO and other "cleaners" -
ATF is commonly mentioned - can help if the issue is varnish build up, but
they can't put metal back on a worn surface.
I believe the noise is coming from the lifter itself. There's a spring
inside the lifter that should keep it a "zero lash" but the spring can't
resist the compression of the pushrod. I know that sometimes when I have
only one lifter noisy and stick my head inside the engine compartment it's
very clear that the noise is coming from the bowels of the engine, not the
head.
I have heard and read in many places that noisy lifters, despite the
terrible sound, will not damage an engine. If you think you're going to
rebuild that engine sometime in the next year or so then I'd be tempted to
let the vehicle sit. What the hell, you're going to rebuild it anyway, so
having sit certainly isn't going to damage anything you wouldn't be
replacing in the course of a regular rebuild, and it sure would mean less
stress on you.
---------------------------------------------------------------
Tom Young '81 Vanagon
Lafayette, CA 94549 '82 Westfalia
---------------------------------------------------------------
----- Original Message -----
From: "Anonymous Digest" <jbrush@AROS.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, August 08, 2004 2:42 PM
Subject: Noisy lifters, rockers, at startup, etc (long)
> Hi all,
>
> I bought this up on the air cooled list, so if Wil, and others who offered
to
> help recall it, I don't want you to think I am second guessing, or
doubting your
> expertise. I appreciate the advice, and am just searching for more
opinions and
> theories.
>
> My air cooled, at 200K, is starting up with clacking lifters/rocker arms
way too
> often. Circumstances only allow me to drive it three or four days each
month, so
> for much of this year, it sits for at least several weeks between starts.
In
> case anyone is curious, its an insurance issue, as I cannot afford to
insure it
> right now, but they do allow me to drive it four days a months, for a tiny
flat
> fee, but that means I cannot just drive it around the neighborhood every
few
> days to keep it running happy, so I get one or two weekends out of it, if
I plan
> accordingly :-)
>
> I take a long trip, it runs great, and I sure feel badly about having to
let it
> sit for so long before I can drive it. I do so enjoy it. :-) It sits for
about
> two an a half weeks, and when I finally start it up , I get more than
just one
> lifter/rocker arm tapping, there are a mess of em "not happy" and it takes
> nearly twenty minutes of cruising easily through the neighborhoods to
quiet it
> down. Not long ago, before I took it out to try and silence it, I put in
about
> half a quart of Marvel Mystery Oil, as that has helped on rare occasions
before.
> Did it help? Certainly not within five or ten minutes of idling. Its still
in
> the crankcase, and I still have the issue when I start it up, so I am not
sure
> it did much good.
>
> When it is so gosh-awful- noisy, it still runs just great, although it
sounds
> like a V10 diesel, and its a bit embarassing to get those looks from folks
as I
> go by, or sit at a light.
>
> As an aside, it does blow a lot of oil on trips, and so I am quite certain
that
> I always have pretty fresh oil in the crankcase, as it gets a full change
on a
> 1200 mile trip, and I ditch it, and the filter, after every adventure. I
feel
> certain that it has never suffered from dirty oil over its lifetime, and
that
> what is in there now is pretty fresh oil. Its been changed more than four
times
> this year so far, and the problem remains.
>
> I have taken to starting it up and letting it run for about ten or fifteen
> minutes every other day, in hopes of avoiding such stress with weeks
between
> starts. After two days, it will start up noisy, quiet down in ~15-20
secs, but
> for a bit of a tap. I let it idle at about 1500RPM for ten minutes or so.
By
> that time, it is running as quiet, and as "happy sounding" as it ever has,
the
> oil temp is around 150 or 160 by then, in the summer heat.
>
> I have tried cranking the engine with the spark disconnected in order to
get
> pressure up before letting it start, but I guess there is just not enough
oil
> pressure at that slow speed to do much of any good. Used to help, but not
> anymore.
>
> Given the cash, I would just buy a new motor. Till then, I would like to
solicit
> ideas and opinions, especially from those who "suffer" from this, and who
have
> been inside the 2.0L aircooled motors. I am more of a V8 expert, so what I
know
> about the internals of these beasts, I have learned from you folks.
>
> I switched from the FLAPS Bosche filters to the Mahles from our online
vendors a
> few years ago, although I don't blame the filters. With regards to the
filter
> and the pressure valve on an air cooled engine, I fail to see the need for
it,
> as the filter sits vertical, and not tilted as on the water cooled motor,
and is
> always full of oil, so I have no idea how such a pressure valve can have
any
> effect on this engine. I'd like to hear the technical, oil flow
explanation for
> it, if it is really considered critical. That notwithstanding, I use the
better
> ones anyway, but so far, I see no proof that they do any better regarding
this
> problem.
>
> My biggest concern is the excessive wear and damage I am doing to the
engine,
> and I am soliciting thoughts as to what is the lesser of the evils.
>
> In my mind, the noise I am hearing is the clatter of the rocker arm being
> slightly "loose" if you will, as the lifter pumps up. Its not much of a
> clearance deviation, but I assume its enough to make the racket. I can't
see
> adjusting the lifters, as they do quiet down eventually, and the motor is
as
> smooth as that "baby's butt" we all relate to :-) Would an adjustment seem
> necessary, or useful?
>
> Is that noise actually what I think it is, or is it a cam/lifter issue
that is
> stressing the cam lobes, and gonna fail one day if I let it continue? Its
loud,
> but I am assuming its the rocker arm wacking the valve stem/spring, as
well as
> the pushrod. Yes or no?
>
> I use 20-50W exclusively, cannot afford to use synthetic as the engine has
a
> "blow by" problem and blows a lot of oil out the main seals and probably
other
> places. Plus, changing over in a motor this old seems like a bad idea.
>
> It would seem to me that a lighter weight oil would be called for, to pump
up
> the lifters faster, but I am just guessing about that.
>
> Since noise like this is caused by something stressing out, or being out
of
> adjustment, I assume I am going to hose something one day unless I find a
> solution. Are there other components are taking the beating in this "dry
lifter
> when it starts up" scenario?
>
> Is replacing the lifters a reasonable option, or will that cause undue
wear on
> the cam and create a different, albeit still fatal, problem? Could the
problem
> actually be somewhere else in the oil flow path, and is only manifesting
itself
> in the lifter problem?
>
> If I end up doing nothing, I would like to know what the consensus is, as
to
> which is the lesser of the two destructive evils, starting it up every
day, or
> every other day, and idling it at ~1500RPM for a fifteen minutes, or
letting it
> sit for three weeks, and then starting it up ,and driving it till the
hellacious
> noise drops away?
>
> I know this is kind of long. Just wanted to get out the facts and avoid
> confusion if I can.
>
> Thanks for any advice. I appreciate it.
>
> John
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