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Re: Blue smoke -sequel

To: <spridgets@autox.team.net>
Subject: Re: Blue smoke -sequel
Date: Tue, 10 Jul 2001 20:46:27 +0100
References: <001101c10971$f1764920$c06287d9@upstairs> <3B4B5635.1F50552F@core.com>
Hi again.
Compression just read at
Dry:
200/190/180/190
wet:
200/200/200/200

exhaust smoke definately bluer (i.e. no longer whitish) with PCV
reconnected.

Cleaner looking at constant 3000rpm, but may be just dispersing
quicker.
more on throttle blip than on shut down.

Have run on standard 10W/50 throughout. Changed at 1000 miles when
head retorqued.

I didnt assemble block - it went to engineer who re-bored +40 and
assembled craank and pistons.  I brought it home and assembled the
rest. Stood for a while before first use.

When head was off last week bores looked unmarked. No apparent glaze,
but fine criss-cross marks that were on bores have all gone.

Oh, and yes the inlet valves do have those little rubber collars
fitted!

Thanks for evceryones' forbearance (now there's a word one dosn't hear
every day!)

Guy

----- 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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