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Discussion Topic:
Idle mixture screws:
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fortyford |
11-02-2009 @ 9:56 PM
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Member
Posts: 218
Joined: Nov 2009
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Is there a real easy way to get the idle mixture screws adjusted right? I put a rebuilt carb on my 40 and can't seem to get set right.It doesn't seem to want to smooth out and I am getting popping sound out of duel exhaust.
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TomO |
11-03-2009 @ 7:26 AM
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Senior
Posts: 7252
Joined: Oct 2009
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If you have a vacuum gauge, set each side for the highest steady vacuum reading. If you don't have a one, turn each screw in until the engine is about to die and then back it out 1/2 turn. This will put you within 1/8 turn of optimum. If you have to turn a screw more than 1/8 turn from the initial point, the carburetor is not working properly.
Tom
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supereal |
11-03-2009 @ 9:02 AM
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Senior
Posts: 6819
Joined: Oct 2009
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We use a vacuum gauge too, as TomO suggests. If you find that the idle screws don't function properly, pull them out and look for signs that they have been overtightened. This will show up as indented rings around the tip of the needle. If so, it is also likely that the seats have been damaged, as well.
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BERTHA |
12-04-2009 @ 6:43 AM
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New Member
Posts: 129
Joined: Nov 2009
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You may have an exhaust valve that is not sealing properly. Remove plug wire one at a time and check check rpm drop to isolate cylinder. Do you have good compression? With duals,listen at tailpipe you may be able to determine which bank has the misfire.
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alanwoodieman |
12-04-2009 @ 9:35 AM
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Senior
Posts: 868
Joined: Oct 2009
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check to make sure the carb is tight to the intake, good gaket, all vacuum lines are tight, a vacuum leak will sometimes cause your problems
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