> hmmm, compression has not reduced in anyway, though maybe an oil ring has
> let go. I guess it is most likely the guides, hopefully not a cracked
> piston.
>
> The bearings are .020. None show any sign of copper, though I guess it
> wouldn't have to get down that far to cause a knock. Is that right?
>
> I am thinking of changing the bearings anyway and taking it from there. I
> can't be bothered pulling the motor completely to bits yet, though it is
> pretty horrible do this job with the engine in place.
>
> thanks jarrid
>
> Greg
>
>
>
>
>
>
> ----- Original Message -----
> From: Jarrid Gross <JGross@econolite.com>
> To: Greg Locke <glocke@ihug.co.nz>; Alpine list <alpines@autox.team.net>
> Sent: Wednesday, 7 March 2001 12:47
> Subject: RE: motor problem
>
>
> > Greg quoth,
> >
> >
> > >1725 engine with about 5000 miles on it after reboring and rebearing.
> > >Suddenly started making a big end type knock on start up, that would
> > >disappear as soon as oil pressure light went out. At same time, when
> > >driving, if I pulled my foot off the accelerator, then floored it, a
big
> > >puff of blue smoke emits from the exhaust, and the engine pinks wildly
> for
> > a
> > >mo, then pulls fine with no smoke.
> >
> > Only bearing clearances will cause the big end knock.
> > The upside down oil filter on our engines certainly doesnt help.
> >
> > The oil smoke is a secondary issue to the knock.
> > Could be guides, rings or cracked piston.
> > Compression testing might find the bad cylinder, but then
> > again the plugs should tell the story too.
> >
> >
> > Jarrid Gross
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