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Re: Passing AZ emissions and carb adjustments

To: "datsunmike" <datsunmike@nyc.rr.com>,
Subject: Re: Passing AZ emissions and carb adjustments
From: "J Friederich" <jfried@anv.net>
Date: Thu, 17 Aug 2000 17:16:07 -0700
Unfortunately I have to put up with this every year in Nevada as well.  To
make it even more difficult, I've got Solex carbs & cam.  In order to get it
to pass, I've got to change 4 main fuel, 4 main air, and 4 pilot jets.  Then
I've got to mess with with screw adjustments.  This last year it took 8
trips to the smog station (thankfully only a mile away) to get it all
'right'.  At the point it'll pass smog, I've nearly got to push it down the
street, as it'll barely run under its own power.

The fun part is getting it all 'right' again.

-john f
'69 2000 Solex


-----Original Message-----
From: datsunmike <datsunmike@nyc.rr.com>
To: John F Sandhoff <sandhoff@csus.edu>; Jim Williams
<jamesd_williams@yahoo.com>
Cc: datsun-roadsters@autox.team.net <datsun-roadsters@autox.team.net>
Date: Wednesday, August 16, 2000 4:44 PM
Subject: Re: Passing AZ emissions and carb adjustments


>Not in NY either if car is more than 25 YO.
>
>----- Original Message -----
>From: John F Sandhoff <sandhoff@csus.edu>
>To: Jim Williams <jamesd_williams@yahoo.com>
>Cc: <datsun-roadsters@autox.team.net>
>Sent: Wednesday, August 16, 2000 2:12 PM
>Subject: Re: Passing AZ emissions and carb adjustments
>
>
>> I'm NOT an emissions expert (well, people standing behind my
>> Mustang may disagree :-) ) but I'll add about a penny's worth anyway
>>
>> Jim writes:
>> > Well I failed my first time through the AZ emissions
>> > test, but not by much... Hyrocarbons were low and Co2
>> > was good at high speed, but the Co2 failed at idle...
>>
>> I do not believe that this is a 'lean the car out' issue. Leaning
>> the mixture affects hydrocarbons more than CO (I'm guessing you
>> meant carbon monoxide, not carbon dioxide).
>>
>> By the way, it is possible to INCREASE your unburned hydrocarbon
>> count by LEANING the mixture! My 1200 used to do that - it's called
>> a 'lean burn' condition - not enough fuel for a complete burn, leaving
>> behind unburned gas that goes out the tailpipe. That's why the 'lean
>> burn' engines of a couple decades back had emissions problems
>> (we'll avoid discussing stratification - an old idea that pops up now
>> and again)
>>
>> > I had the timing at 0, dwell right on, idle at 1500,
>> > and SU carbs leaned to a 1/4 turn from the top stop...
>>
>> That's a high idle. Good for testing, bad for driving.
>>
>> > Just want to confirm that the SUs lean out as the
>> > mixture ring at the bottom of the carb compreses the
>> > car adjustment spring and moves the nozzle upward...
>>
>> Yup. But if you're 1/4 turn (hmmm, one and a half 'flats') from
>> full-on lean, your carbs are a bit out of whack. Typical setting is
>> a full 2-3 turns. Are the needles set right (Shoulder flush with
>> the piston body)? Do the jets look good (nice and round, not
>> oval from wear)?
>>
>> > Can anyone tell me if there are leaner needles I can
>> > purchase for leaner idle?
>>
>> High altitude needles. Keith Williams knows all about R-16 needles :-)
>> If someone donates him a U-20 maybe he'll figure them out, too :-) :-)
>>
>> > Passing an emissions test for a 32 year old car is a
>> > pain...
>>
>> Not in California any more :-) Sorry, I couldn't help it...
>>
>> -- John
>>      John F Sandhoff   sandhoff@csus.edu   Sacramento, CA
>>
>
>


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