[V8] now overhaul

[dsaad at icehouse.net]

Thanks for pointing this all out to me.
Definitely more to think about.

So - if you had the rings and rod bearings in your hand, would you replace them
during a valve job, without honing cylinders - or just leave them (rings) alone?

Based on the can of worms that opening up one of these motors spills out,
I might just be tempted to install the donor motor as is - assuming of course I
can get it to run.
And in that case, it will have the automatic cams in it. Anybody see a big
problem with that?


Dave

I get the feeling I am going to be driving my beater truck for a while...




Quoting NicolCS at aol.com:

> I<snip>
> n a message dated 5/26/2006 7:57:51 AM Pacific Daylight Time,
> dsaad at icehouse.net writes:
> I almost certainly want a set. If my motor has good bores, I would rather
> re-ring it than put in another used block. The only issue left would be
> honing,
> but I would gamble that the rings would seat properly, again given that the
> bores were not too worn.
> I am sure others in my situation would feel the same.
> and someone else wrote:
> I'd think just running a ball hone through the cylinders would be
> plenty, assuming there's no visible chunks missing. <unsnip>
>
> A ball hone won't provide the correct surface. It will leave a combination
> of
> silicon and aluminum at the surface.  What you have to do is a procedure
> that
> removes the aluminum from the surface, leaving silicon as the surface.  If
> you don't remove the aluminum at the cylinder wall , it will gall when the
> aluminum piston rubs it leading to a total melt-down.  (Think Chevy Vega).
> In my
> experience with aluminum/silicon bores, the bore never wears unless there's
> a
> catastrophic event, such as coolant in the cylinders.  What wears are the
> piston ring lands.  With the rings flopping around, oil control and
> compression
> goes out the window.  A re-ring won't fix that.  The next issue is that
> German
> engines are set-up with very tight bore-to-piston clearances, usually around
> .001" +/-.0003.  While the bores usually don't wear much, the pistons do,
> another
> reason to lean towards new pistons.
> So: Silicon hone, replace rings, replace pistons (figure $100 each),
> probably
> at least $2000 to overhaul, or replace with good used.  The latter would be
> my choice.
> Craig Nicol
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