Part 2: Reading Plugs, pistons, and valves (with Pics)

[Shannen Durphey]

Everybody's saying rich, rich... I dunno.

seriously.

What I see is the thickest,blackest carbon is built up around the
edges of the piston, except the area under the intake valves which is
clean.  What I would think is that the combustion temps are lowest at
the outside of the chamber.  Between the low temps and the incoming
fuel wash there's no chance for carbon to build up on some areas of
the piston. In general the outside edges seem to have that
"looser","flaky" carbon buildup while the insides have a sort of
"glazed" or "cured" buildup.  Again, heat...

Finding the why of low temps is the thing....

Yeah, too much fuel.  Yeah, too cold t-stat.  Yeah, too cool intake
charge.  Yeah, fuel issues.  Yeah, insufficient spark to ignite a good
burn. Yeah, aluminum heads draw heat from the combustion chambers and
they're cooler in the back than the front due to coolant circulation. 
Yeah, it all works together.  But what is the one thing that's doing
it??

Or is it one thing?

Now you guys know what you've been discussing, I haven't followed as
closely as I could.  But I would look at this and think about heat,
chamber temps, and the causes of more or less of it.  Then I'd prolly
work to rich, or wrong plugs, or cool engine temps, whatever.  

I'd be nervous about starting at "too rich" and working my way back to
carbon buildup, since I already know that too rich leads to carbon
buildup and I have the answer before I ever get serious with the
question.

Am I off the wall?
Hmm...  Let me rephrase that.
Anybody wanna correct/add/subtract something?  I'm still a thoughtful
beginner....

Shannen

Programmer wrote:
> 
> Yep--that's right. <g> Probably couldn't
> be any deeper...sure looks rich around the piston
> edges. What's the plug part numbers btw ??
> 
> Lyndon.
> ----- Original Message -----
> From: <timsiford at hushmail.com>
> To: <gmecm at diy-efi.org>
> Sent: Saturday, December 02, 2000 7:00 PM
> Subject: Re: Part 2: Reading Plugs, pistons, and valves (with Pics)
> 
> > I thought that the plugs had the correct reach.  But, then again, what is
> > the 'correct' reach?  From the Pics you can see that only the end portion
> > of the plug was in the chamber.  That looks good to me.  Is that right?
> >
> > Tim
> >
> >
> > At Sat, 2 Dec 2000 18:43:56 -0700, "Programmer" <nwester at eidnet.org>
> wrote:
> >
> > >
> > >Looked at the pics...Shouldn't those plugs have a taper seat ? Did they
> > >sell
> > >you plugs with the wrong reach ??
> > >Orange is just fuel additive package...looks like it was
> > >definitely on the fat side of tuning.
> > >
> > >Lyndon
> > >----- Original Message -----
> > >From: <timsiford at hushmail.com>
> > >To: <gmecm at diy-efi.org>
> > >Sent: Saturday, December 02, 2000 4:45 PM
> > >Subject: Part 2: Reading Plugs, pistons, and valves (with Pics)
> > >
> > >
> > >> I have pics of my head gasket swap (teardown).  Any advice you can
> > >offer
> > >> would be great.  All in all ... I 'think' everything looks good.
> > >But,
> > >this
> > >> is only the second time I have had the heads off.  The only problem
> > >is
> > >that
> > >> I see lots of Orange.  I don't know why everything is so Orange.
> > >Anyone?
> > >>  I have pics of the plugs, the pistons, and the head chambers from
> > >each
> > >> side.
> > >>
> > >> Also, these pictures clearly document how the rear cylinders run rich
> > >with
> > >> the TPIS MiniRam.
> > >>
> > >> Go to ...
> > >> http://www.picturetrail.com/traxion
> > >> Click on '1990 IROC Z28 Pictures' and then you can view thumbnails
> > >on the
> > >> left.
> > >>
> > >> BTW - www.picturetrail.com is pretty cool.  I uploaded all of my pics
> > >through
> > >> this free service.
> > >>
> > >> Again, any advice or help is appreciated.
> > >>
> > >> Tim
> > >
> > >--------------------------------------------------------------------
> > >--------
> > >To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
> > >in the body of a message (not the subject) to majordomo at lists.diy-efi.org
> > >
> 
> ----------------------------------------------------------------------------
> To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
> in the body of a message (not the subject) to majordomo at lists.diy-efi.org
----------------------------------------------------------------------------
To unsubscribe from gmecm, send "unsubscribe gmecm" (without the quotes)
in the body of a message (not the subject) to majordomo at lists.diy-efi.org