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Old 02-07-2011, 05:39 AM
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An OFTEN overlooked passage that needs to be cleaned, and is often plugged or obstructed, is the small, ~0.028" orifice that connects the secondary discharge port well to the main fuel reservoir.

Because it's on a 'ledge', it's prone to have deposits clog it, and it is hard to see if you're not specifically looking for it.

Be careful to not enlarge this orifice, it is also part of the secondary air/fuel ratio calibration and if made too large, will cause the secondary to go pig rich under extended WOT operation.

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