[V8] now overhaul
dsaad at icehouse.net
dsaad at icehouse.net
Fri May 26 16:42:55 EDT 2006
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?
I get the feeling I am going to be driving my beater truck for a while...
Quoting NicolCS at aol.com:
> 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
> 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
> silicon and aluminum at the surface. What you have to do is a procedure
> 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
> catastrophic event, such as coolant in the cylinders. What wears are the
> piston ring lands. With the rings flopping around, oil control and
> goes out the window. A re-ring won't fix that. The next issue is that
> 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,
> reason to lean towards new pistons.
> So: Silicon hone, replace rings, replace pistons (figure $100 each),
> at least $2000 to overhaul, or replace with good used. The latter would be
> my choice.
> Craig Nicol
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