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Re: Compression w/i 10% variance (but < 175 lbs)

To: "Peter Schauss" <schauss@worldnet.att.net>, <healeys@autox.team.net>
Subject: Re: Compression w/i 10% variance (but < 175 lbs)
From: "davidwjones" <davidwjones@cox.net>
Date: Mon, 2 Jan 2006 13:23:03 -0500
My BT7 gave me about 10-15 lbs of pressure at idle, and about 38-40 lbs of
pressure, hot, at speed, from the day I got it. --I drove it that way for
about 10 years, before tearing it down during it's total restoration. It
didn't consume an appreciable amount of oil, didn't smoke (at least that I
could tell, it smoked slightly anyway, because in those days I ran a little
marvel mystery oil in the gasoline). - I don't know what the compression
was......it ran strong in my opinion, and I think I felt that what I didn't
know, could not hurt me. (or dent my wallet).
I drove the car HARD back then, and still, even with the lower oil pressure,
when disassembled, the engine showed no signs of abnormal wear.
A new oil pump and rebuild brought the pressure up to a hair higher than
factory spec. -But I'll never know whether it was the pump, or all of the new
bearings / bushings etc, that made the difference. nor really care.
I just kept an eye on it during those ten years, and changed the oil on a
strict schedule. -I never saw a change, and I'm assuming that if I had kept
on, without the rebuild, it'd probably still be serviceable.
Dave J.
  ----- Original Message -----
  From: Peter Schauss
  To: 'Healey email list'
  Sent: Monday, January 02, 2006 1:01 PM
  Subject: RE: Compression w/i 10% variance (but < 175 lbs)


  Dave,

  Mine was like that when I got it although I think that my oil pressure was
a
  shade under 40# fully warmed up.  The car used about 1/2 a quart of oil a
  week and gave off a bit of blue smoke under heavy acceleration.  The number
  6 intake valve made a good bit of noise, presumably due to a bad lobe on
the
  cam shaft.

  I ran it that way for 27k miles (4 years) before it broke a ring, forcing
me
  to rebuild it.  I was lucky enough to be about 200 feet from the end of my
  driveway when the ring broke.  YMMV.

  Peter Schauss
  1963 BJ7
  1980 MGB

  -----Original Message-----
  From: owner-healeys@autox.team.net [mailto:owner-healeys@autox.team.net] On
  Behalf Of Dave Leland
  Sent: Monday, January 02, 2006 8:46 AM
  To: Healey email list
  Subject: Compression w/i 10% variance (but < 175 lbs)

  Does anyone have any thoughts on my compression
  readings below?   My Haynes manual says to expect
  about 175 lbs and I'm lower (but consistently lower).

  How long can I wait for a rebuild is my main concern.

  #1-  147 lbs
  #2-  150 lbs
  #3-  149 lbs
  #4-  151 lbs
  #5-  148 lbs
  #6-  150 lbs

  The car is a BJ7 with probably 80k miles and oil
  pressure is 30-35lbs when warmed up at cruising speed.
   Thanks for your thoughts.

  Dave Leland
  Nashville, TN




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