<VV> Failed emissions test

[burkhard at rochester.rr.com]

This is just an sniffer-in the pipe test while idling, right?  They are 
usally "no biggee" to deal with and shouldn't be a cause for alarm. 
Suggested approaches

1.  If they sniff right where you have teh idle speed set, make sure 
it's set a little high.  Go for 1000 rpm (you didn't say if this an 
automatic, but if it is you don't want to go too high or it will be 
quite a lurch on engaging "D"). If they rev it up to take the 
reading "off-idle", don't bother fiddling with the idle speed, though.

2.  Retard the static spark advance by 10 deg from where you now have 
it (10 deg BTC sounds a bit low already though... what is the spec?).  
This will tend to make the engine run hot (because combustion rates 
will be slower exhaust temps will be higher), so drive it 
conservatively and try to make this "adjustment" nearby the inspection 
place.  You don't want to drive the car hard for 20 miles and burn an 
exhaust valve.  The hotter exhaust will do wonders to oxidize the HC 
and CO. :-)

3.  Enlean the idle fuel mixture a bit.  It should already be at lean 
limit, but if you boosted the idle speed a little, you can get away 
with a bit more.  The extra oxygen in the exhaust will do wonders to 
oxidize HC & CO. :-)

You might not need all 3 steps...  If it's cheap/convenient to retry, 
experiment a bit.  These unloaded "concentration only" tests are 
generally quite easy to pass. Life gets a little tougher in areas that 
require chassis dyno tests that include NOx emission measurements. They 
generally exempt old cars for those, though.

Let us know how you make out.  Send me an email with the "VV" tags 
removed from the subject line if you have an off-list question.  My 
mail gets auto-sorted based on teh VV tag, so sometimes, that stuff 
takes weeks to read (or gets skipped entirely).

best regards-
Jim Burkhard




----- Original Message -----
From: "D. Monasterio" <dmonasterio at megared.net.mx>
Date: Friday, August 17, 2007 2:18 pm
Subject: <VV> Failed emissions test
To: virtualvairs <virtualvairs at corvair.org>

>     Last week (finally) installed the rebuilt engine (110) on my 
> new toy (64 Deluxe GB). It started at first attempt with the usual 
> valve clattering for a couple of minutes, then smooth running. Got 
> it running for about 2 hours (oil and filter change at first half 
> hour). Did a final tune up with new 8mm wires, 7502 plugs at 
> 0.035", Pertronix, 10degrees advance, cleaned and calibrated carbs 
> (floats at 1 1/6"). Fuel pump is a mechanical.
>     It runs smoothly on regular gas at 4,500ft altitude so, I 
> decided to take her for the emissions test in order to get her new 
> Mexican license plates. It failed !! 
>     The maximum allowed HC is 300 ppm and CO is 3.00 % but the 
> brier's engine couldn't be put on less than 480 ppm (HC)with the 
> 3.00 % on CO.
>     Didn't have this trouble with the 140 HP engine in the 67 
> cpe. (25,000 miles) nor the 110 HP engine in the 62 Rampy (12,000 
> miles).     What could I have made wrong ?
> 
>     As always... Thanks in advance.
> 
>     Daniel Monasterio
>     
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