On 11/5/2012 1:52 PM, Existential Angst wrote:
Awl --
....

So the Q is: what can one "dump" into one's gastank, and how much, without
gumming up the works? Including all these catalytic converters. Mebbe it's
better to dump stuff in, say, the lawnmower??

And what do I mean by "stuff"?
Unknown mixes of 2-stroke gas, kerosene, paint thinner, small amounts of old
oil, any combustible really.
....

Biggest problems w/ modern vehicles (injected w/ catalytic converters
and OBD computers, basically) that I can see otomh are

a) contaminated/used oil w/ particulates to plug inline filters and
perhaps injectors and

b) impurities that are harmful to the catalytic material (Pt) in the
converter. Pb is the probably the most but it's very unlikely to find
leaded gas any longer (but perhaps some of the non-fuel items or for old
2-cycle I don't know?). Other specific metals I know of that aren't
good include Zn, Mn, Ph which exist or existed in at least some engine
cleaners before. Of course, Si is another which is why it is bad
when/if lose a head gasket on converter as well as the other nasties
that does because it is common in antifreezes...

All in all, I'd tend to find something else to do with most of it,
myself even though in small enough amounts and infrequently enough it's
not likely to do serious damage I figure why take a chance on a sizable
investment for the cost of a little aggravation? (Of course, it's a lot
easier to get rid of stuff on 2000 A and large gravel driveways than on
a city lot w/ everything paved over or lawn... )

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