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Throttle Problem


tweeter6216

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I have a Briggs opposed twin with the carb mounted on the two-piece intake. When I give it throttle the engine sputters and weakens for a second or two before more power is received. I tried adjusting the main jet screw on the front of the carb but I cant get it right.
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I fixed my single cylinder Kohler by adjusting the main jet, It took some fooling around, but I Finally got it right.
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Hi, Try adjusting it by the Briggs manual. Some of these engines have fixed main jet carbs, with only a low speed adjust. Check the float level also you might want to check the compression to see both cyls are about equal. You might have an intake valve leaking a little bit. Also check the mainfold for leaks. Not all that common, but occasionally happen on the 2 piece manifolds where they are glued together. It won't be a very large leak or the engine would run worse otherwise. Are your plugs good and gapped right? Just a few thoughts to start looking at. Look at the carb and base gaskets first. Al Eden.
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I had a B/S Vanguard that could not be properly adjusted. It had a fixed jet carb. I eventually enlarged the main jet by .001 inch and it ran beautifully. The slightest change in an engine can throw off a fixed jet carb. Fixed jet carbs are nearly always set toward the lean side at the factory for emissions. They nearly always run better if made a little richer. Caution! Don't drill a jet unless you absoletely know to do it properly. I don't think they are available separately, and if you screw up, you will be buying a new carb. My controversial two cents!
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