Date: Sat, 26 Jan 2002 11:25:28 -0500
Reply-To: "G. Matthew Bulley" <gmbulley@BULLEY-HEWLETT.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "G. Matthew Bulley" <gmbulley@BULLEY-HEWLETT.COM>
Organization: Bulley-Hewlett
Subject: Re: Aircooled lifter noise
In-Reply-To: <20020126.002916.-334701.53.wilden1@juno.com>
Content-Type: text/plain; charset="US-ASCII"
Your hydraulic aircooled should have no valve noise after the first
10-15 seconds, if you drive it daily. During this startup period you may
hear a clittitttickiicktity sound as the lifters re-fill from a slight
loss of oil, then silence.
One or two of the lifters can bleed down completely if the van sits
un-started for a week or so. If so, the sound will be closer to a
clattackatttacky sound, and will take full warm up of 10-15 minutes to
disappear. In either case, no lasting harm is done from the temporary
lack of adjustment, as long as the valves reach full adjustment within a
reasonable period of time (within the first few miles of travel).
Jake Raby and I have a difference of opinion on this matter of
un-adjusted valve clatter, and I think I should point that out. It is
his assertion that valve clatter is (at least in part) the sound of the
valve slamming closed against the seat, and this in turn is partly to
blame for valve seat destruction or loosening. I disagree.
I propose that valve clatter is produced solely as the slack in the
valve train is eliminated by the lobe of the cam coming around and
slamming the rocker arm tip against the tip of the valve. Having slack
in the distance between the rocker arm tip and the valve does NOT slam
the valve CLOSED (as Jake asserts), because the entire valve train is
under spring load as the cam lobe retreats, and therefore there is no
sudden slam, jus the normal valve closing. Think about it.
Either way, well-adjusted valves are important to longevity and
efficiency for your motor, so let's get them right.
If your valves are still noisy after a few miles on the road, I'd
suggest a chemical treatment to free up the sticky lifters PRIOR to
messing with the adjustment. Sometimes crud fouls the hydraulic lifters.
I wrote a LENGTHY description of how to do this back in 1998 or
thereabouts, and I am sure you can find it in the archive.
In essence, you are going to swap your oil out for a 50/50 mix of 10-w30
and ATF transmission fluid and a new filter; high-idle it in the
driveway for 30 minutes (do NOT drive it). You could also include an
entire quart of MMO don't overfill.
During the high idle, the clatter will go away, and you will smile, but
keep it at high-idle for a full :30 minutes to continue the clean up.
Swap the filter and oil to whatever you normally use. Drive it for
100-300 miles. Change oil and filter again.
*IF* the clatter doesn't go away, readjust the valves. As for the great
"preload" debate, I've used 2 turns, 1 turn, 1/2 turn, and no preload. I
have no opinion other than to say that 2 turns is (IMHO) excessive.
Last note, some say that MANN or VW OEM filters are best to solve this
issue, particularly for WATER cooled flat fours, as they have better
flow characteristics. I won't even go there. They may be right, but I
can't justify the $6.00 cost. I don't share the philosophy that oil has
to be sanitized to be clean enough to prevent wear, and I don't believe
that *some* cheaper filters are just fine if you keep your oil changed
regularly.
I use Fram PH8A, which is a MUCH larger filter than the OEM, and has
been my filter of choice for type 4's since the mid eighties. Buy the
"extra guard" if your FLAPS has it.
Telling you this though is like telling the Mother's Against Drunk
Driving list that I put bourbon in my kid's night-time feeding so that
they will sleep well. Flame all you want, you won't get me to switch.
(from the bourbon, or the Fram)
Happy motoring.
From historic, walkable Mount Olive, NC,
G. Matthew Bulley
Bulley-Hewlett
Corporate Communications
Business: www.bulley-hewlett.com
Alliance: www.ntara.com
Home: www.MountOliveNC.info
