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1500 ZS carb question

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ahpook

ahpook

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You know that stupid little "idle richness adjustment screw" on the right side of the carb, looking at it from the fender? The Haynes manual says to adjust using a CO meter, which I don't have, nor do any of the local garages I've called. How does one set it without a meter, and what exactly is it there for?
Thanks for any help,
George
 
It allows air to bypass the throttle plate and jets there by leaning your mixture. You can set it by ear (piston lift method) or with a Colortune (ususually run you about $50.00). Or.... I am sure someone else knows a cool way to set idle mixture.
 
Most info I find says to leave it closed unless you're trying to fine tune it to meet emissions. I keep mine closed since I can get it close enough to run well with the needle adjustment, and I am exempt from emissions testing.
 
exempt from emissions? me too. isn't it wonderful? I've been removing everything I can, emissions-wise, and the engine just runs better and better...
 
Yes, being exempt is a good thing. Here's hoping Ohio never decides to follow Pennsylvania's example. They didn't exempt old vehicles, and my dad's 1947 Lincoln failed so badly they couldn't re-calibrate their sniffer. Serves them right, expecting a 60 year old car with a V-12 and only a muffler to pass. Last I heard, I think he did say they finally came to their senses and made exceptions for pre-smog cars.
 
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