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Subject:CO Adjusting Screw. PO Set it All The Way In? Base Setting?
From:neil n
Date:Thu, 21 Jun 2012 11:36:14 -0700

Hi all.

The protective cap on the CO screw was drilled and tapped. Checked CO screw
setting. It's all the way in.

Emissions test results seemed quite low (HO, CO, NOx), plug colour was
grey.  Image:

https://lh3.googleusercontent.com/-HsjvHzL5ew0/T6iOlOpuTII/AAAAAAAAFvI/Gox0nzYwBXg/s640/1988%2520Westy%2520Spark%2520Plugs%2520.jpg

Engine has a pretty consistent surge coasting in 2nd or 3rd gear @ ~ 2500
RPM down, and a mysterious stall, engine cold. Stall happens once. When
engine temp higher, engine runs "ok".

Reading this post from Dennis:
http://gerry.vanagon.com/cgi-bin/wa.exe?A2=ind0201A&L=vanagon&P=R7346&m=155177
I have to wonder if the CO adjustment is currently affecting the fuel
shut
off process thus causing surging. A fuel cut off issue was one of my
original thought towards the surging issue.

I've done a full tune up, new O2 sensor & cat, cleaned grounds,
repositioned AFM wiper, adjusted throttle valve switch. (it consistently
closes just off idle), swapped idle stabilization module (old one causes
idle issues when swapped back in).

I don't have a sniffer, CO port is badly corroded.

I've seen posts in archives suggesting a base setting for CO adjust screw
is anywhere from 1.5 to 3.5 turns from seated in.

Can anyone confirm or suggest a base setting?

Hopefully a sniffer inserted in the tailpipe will suffice to check my work.

Thanks,

Neil.

--
Neil n

65 kb image Myford Ready For Assembly  http://tinyurl.com/64sx4rp

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