[DML] Great Stopped Up Catalytic Converter Debate

["content22207" <brobertson@xxxxxxxxxxxx>]

Re: side by side Messages #39435 and #39436:

The great "catalytic converter stops up because mixture is too rich"
vs "catalytic converter stops up because mixture is too lean" debate.
Fuel mixture may have nothing to do with it:

On the way to get my new B27A, the converter stopped up on my truck.
Classic symptoms: sudden inability to run fuller throttle and no
exhaust pressure at the tail pipe. Nothing was glowing, but that may
be because it was zero degrees outside. The truck's engine is
carbureted, and I've never changed its jet (single barrel), so fuel
mixture wasn't a variable at all. What was, was removal of my smog
pump (air pump). Catalytic converters apparently need fresh air to do
their thing. Without it, they are prone to melt etc. EVERY SINGLE
CONVERTER I'VE EVER HAD PROBLEMS WITH STOPPED UP *AFTER* I REMOVED THE
SMOG PUMP.

Practical DeLo application -- we never had smog pumps to begin with.
Is it any wonder so many of our converters are suddenly stopping up?
Volvo used them on both F series B27 and B28. Did they know something
JZD didn't? Perhaps his zeal to squeeze a PRV into the car without
some of its usual accessories in the way set us up for the spate of
current problems (anyone else notice melted converters seem to be as
common now as bent & broken TABs?).

Delorean3469: pull your plugs and examine them. Their condition will
tell you what kind of a burn you're getting. Black and sooty means the
mixture may well be too rich (you could also have ignition or
compression problems). Clean and white means it's too lean, or
otherwise burning too early/completely.

Bill Robertson
#5939





To address comments privately to the moderating team, please address:
moderators@xxxxxxxxxxx

For more info on the list, tech articles, cars for sale see www.dmcnews.com

To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
     http://groups.yahoo.com/group/dmcnews/

<*> To unsubscribe from this group, send an email to:
     dmcnews-unsubscribe@xxxxxxxxxxxxxxx

<*> Your use of Yahoo! Groups is subject to:
     http://docs.yahoo.com/info/terms/