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MGB Engine dead diagnosis

To: "mgs@autox.team.net" <mgs@Autox.Team.Net>
Subject: MGB Engine dead diagnosis
From: Trevor Boicey <tboicey@brit.ca>
Date: Tue, 29 Sep 1998 01:34:40 -0400
  (Related to my last post about seeking an engine swap
for my dead-today MGB engine...)

  Before I go writing this engine off, I might as well
bounce the situation off the list.

  1970 MGB, 18V673Z engine (later than 1970).

  When running, car goes through phases of HEAVY oil
smoke. For a couple of miles, I might get no smoke that
I can see in the rearview. Then for the next couple of
miles, any time I push the throttle down I get HEAVY
oil smoke, as in embarrassing big clouds that linger
for a few minutes and make pedestrians take alternate
routes.

  Compression is: 125, 60, 20, 105 without oil, then goes
to 140, 80, 40, 150 with oil. Obviously #3 is in a world
of hurt and generally the whole engine seems knackered.

  Head gasket was just installed by me last december when
I opened the engine for an inspection. I am not a trained
eye at these things, but everything looked good at that
time. Engine ran fine since then although used only for a few
hundred miles because of body restoration.

  Normal wisdom seems to say that if oil doesn't improve
compression, then it's a valve problem. However, from
the amount of oil smoke I am putting out, could it be
valves? I am thinking I might have a SEVERE ring problem,
something that oil just isn't really going to hide for
even a few strokes on a compression tester.

  I intend to pull the head off and investigate, but would
like to have a plan first. I don't want to make the car
immobile if the engine is done for, although I guess I could
reassemble with the old gasket and it should run enough so
I can move the car around my driveway.

  Any chance this could be salvageable with a used head
or even less? I am prepared for the eventuality of total
replacement, no big deal, but if there is a chance I might
get away with a cheaper and faster repair, I should explore. I
am not above throwing new rings in as a DPO repair if
it gets the car running again. ;>

-- 
Trevor Boicey, P. Eng.
Ottawa, Canada, tboicey@brit.ca
ICQ #17432933 http://www.brit.ca/~tboicey/

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