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Help on big bear

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87 & 89 big bear running rough, lots of black smoke. Cleaned carb, new needle & seat.

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Also check your air filter and air intake for blockage. Remove air filter to see if it cleans up, but make sure it's reinstalled before you ride.

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This is a trick that I don't usually suggest, unless I feel the person is able to do it. It sounds like you have been into this, so here it goes.

Take the spark plug wire off of the spark plug. With the air intake to the carb taken off, cover the carb with your hand to create an almost air tight seal. engage the starter to create a high vacum inside the carb. This is basically the same as choking the carb, but a much tighter seal. Do it a few times, then connect the spark plug and start it to clear the gas.

What you are doing is drawing air and gas througth the carb. This may dislodge debree and trash in the small passages, as well as draw gass out of the air passages.

If this doesn't work, you can do it while it is running. Put you hand over the carb untill it is about to die, then release. You need to be cautious of backfire, if you do this. And only do this if you are confident you can do it.

I have cleared many carbs like this. But, until you've done it a couple times, you may question it. From my Olds 455 to my B&S edger. If it has a carb, this may work.

Also, if you do it when it is running, you may hear if you have a vacum or intake leak. I have heard them whistle like a tea kettle.

One last caution. hot hot hot, and gas burns... fast...

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