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Re: Blue smoke -sequel

To: "Chris Kotting" <ckotting@core.com>
Subject: Re: Blue smoke -sequel
Date: Tue, 10 Jul 2001 20:55:18 +0100
Cc: <spridgets@autox.team.net>
References: <001101c10971$f1764920$c06287d9@upstairs> <3B4B5635.1F50552F@core.com>
Chris,
there was oil in the intake - I thought it was from the dash pots as I
do keep them filled.

Plugs are clean and dry, light brown electrode, slightly lighter
ceramic centre. all exactly the same.

Guy
Just cos I am known as a petrolhead dosn't mean I like polluting the
environment!

----- Original Message -----
From "Chris Kotting" <ckotting at core.com>
To: "Guy Weller" <guy@weller-lakes.freeserve.co.uk>
Cc: <spridgets@autox.team.net>
Sent: 10 July 2001 20:23
Subject: Re: Blue smoke -sequel


> The blue color would only be present in the exhaust, since it is a
> result of oil being *burned*.  Somehow, oil (and quite a bit of it)
is
> getting into the combustion chambers.
>
> Some thoughts:
>
> Take a look at the inside of the carbs and manifold.  If there is an
> oily film there, you're sucking it in through the crankcase
breather.
> If not, it's either getting past the rings or the valve guides.
>
> What kind of oil did you use during the break-in period?  When did
you
> change it?
>
> How much of an overbore?  Are you *sure* you've got the correct
pistons
> and rings to match the overbore?  (I hesitate to suggest it, but as
> someone else said, sometimes mistakes are made.)
>
> Run a compression test.
>
> Guy Weller wrote:
> >
> > OK, here are some more accurate checks on the problem:
> >
> > Steady tick over at 800rpm.
> > Slight blue colour to exhaust. If run in garage it soon becomes
> > uninhabitable (as does the kitchen and the whole of the rest of
the
> > house 'cos there is an interconnecting door which isn't fume
proof) -
> > not popular with "her indoors".
> > No revs change when I remove oil filler cap. very slight, I mean
only
> > just detectable with the help of imagination, positive pressure at
oil
> > filler cap.
> > Steady stream of air from end of disconnected crank vent hose, can
> > feel it against my face, but no colour in it - i.e not blue even
when
> > directed across white paper.
> >
> > When I blip throttle there is a good belch of exhaust, quite blue
but
> > also whitish cloud. (but it is not steam!) Oily smell.
> >
> > Definately consuming oil, about 1/2 pint per 300 miles I would
guess.
> >
> > Remember, rebore, new pistons and rings 3000 miles ago.
> > Reconditioned head with new valves and valve guides this weekend
> >
> > Guy



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