> From:    George Thorburn <thorgk@ACCESSCOMM.CA>
> Date:    Sun, 20 May 2007 10:35:14 -0600
>
> How much catalyst is there in a new converter?  Is the metal housing
> full?

The working part of the converter is usually a ceramic "brick" or "loaf"
full of little air passages.  The catalyst is on the surface of the
ceramic, lining all the passages.  The ceramic tends to be the same cross
section throughout its length - if the housing tapers from the exhaust
pipe to the body of the converter, there's often not any ceramic in the
tapered part.  Also, the ceramic usually doesn't come right out to the
outer wall of the housing - it runs really hot and there is a little air
space between the ceramic and the housing.

> If a new converter is full where did all the old catalyst go?  Out
> the exhaust?

The tiny pieces went right out the tail pipe.  The bigger ones are
probably in the muffler, like Jim Arnott said.

You might save your margarine tub full of converter guts (don't
accidentally put it on your bread) and take it to the scrap metal place
the next time you go.  The guts are full of platinum and other goodies.
The place where I drop off my aluminum cans to be assimilated (Borg
Steel - no kidding, that's really the name of the place) has a piece of
plywood on the wall with several shapes and sizes of catalytic converters
screwed to it, with a dollar amount on each.  I haven't been by there
for a little while but I seem to remember something like US$5 or $10 for
the bigger ones.  I don't know if they will deal with catalyst guts in a
tub but asking is free.

> Will a new converter last 22 years like the old one did?

Maybe.  In the US, the federal government sets a minimum warranty length
for catalysts and some of the other emissions stuff.  I *think* it used
to be 5 years/50,000 miles but has increased to 8 years/80,000 miles or
possibly more.  So a catalyst on a new car will be designed to last at
least that long.  I don't know if there are any longevity requirements
for replacement catalysts.

Matt Roberds