Sender: <marv@lancaironline.net> (Marvin Kaye)
To: lml@lancaironline.net
Date: Sun, 16 Nov 2003 09:18:19 -0500
Message-ID: <redirect-2740499@logan.com>
From: "Douglas W. Johnson, MD" <Lancair1@bellsouth.net>
Subject: LIV sluggish MP reading on VM1000
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After almost 700 hours over 6.5 years, I finally had a maintenance issue
with my VM1000 setup which I would like to share.  During the last 3
flights, I noticed that the manifold pressure (MP) readings lagged far
behind my throttle adjustments--by 10-30 seconds or so.  I called Vision and
they suggested that the fine screen mesh in the snubber valve which hooks
into the MP sensor might have become fouled.  I found it, removed it,
cleaned it with an acetone bath, and reinstalled it, but had little
improvement in function.  I next sprung for the $20 to just get a new
snubber valve from Vision (which I should have done in the first place), and
all is back to normal now.

In sum, there was no problem with the Vision system, just a slow fouling
over the years with the valve in the line coming off the throttle body to
the MP sensor.  Apparently this is not uncommon, and may be a regular
maintenance issue.  Live and learn...  Thought if might be of interest to
you all.

Douglas W. Johnson, MD, FACR
8265 Riding Club Road
Jacksonville, FL 32256
(904) 642-6016
Lancair1@bellsouth.net