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Discussion Topic:
ADJUSTING DUAL CARBERATORS
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supereal |
09-09-2010 @ 2:22 PM
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Senior
Posts: 6819
Joined: Oct 2009
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If a too high idle is the problem, check both the linkage and the fit of the throttle plates.
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sturgis 39 |
09-09-2010 @ 12:02 PM
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Member
Posts: 74
Joined: Nov 2009
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Thanks for replying Supereal. I thought a vacuum gauge was the proper way to proceed. The throttle idle adjustment screws are backed off as far as they will go. The idle rpm is about 1000. I plan to disconnect the throttle linkage and make sure it is not hanging up. Then i will try the vacuum gauge. Thanks again
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supereal |
09-09-2010 @ 8:47 AM
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Senior
Posts: 6819
Joined: Oct 2009
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When you say "adjust", are you referring to the idle needles? There are only two adjustments on the carb, the idle speed, adjusted by the screw on the throttle stop, and the idle needles, themselves. Otherwise, the only "adjustment" is by changing the main jets. Most multiple carb problems result from a mismatch between the engine vacuum and the size of the inlet, the venturis, of the carb(s). When the combined capacity of the carbs exceeds 300 cfm, problems begin. The best way to adjust the idle circuit needles is with a vacuum gauge. You adjust each, in turn, to get the highest reading. Multiple carbs look "cool", but usually don't produce much operating benefit, if any.benefit
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sturgis 39 |
09-09-2010 @ 1:55 AM
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Member
Posts: 74
Joined: Nov 2009
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WHAT IS THE BEST WAY TO ADJUST DUAL CARBS?
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