Carb issue

slow030

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Picked up troy built pony rider with B&S 17.5 hp single cylinder with nikki carb. Had sat in garage for about 3yrs. Cleaned carb and replaced o ring and gasket, runs good except at low throttle. Surges some, not too bad, and pops at idle . Never had one of these hikki carbs before, is there anything else I can do to fix the problem?
 

Scrubcadet10

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Clean the carb better, or make sure no gaskets are ripped.
Idle circuit possible clogged. If it has a idle mixture screw remove it, (take note of how many turns out the screw is, by screwing it in all the way and counting how many turns until snug)...
once removed grab some carb cleaner, spray it in the hole the screw was in, Maybe even soak the carb in a cleaner...
What's the engine model number? should be located/stamped into the OHV cover.
 

keakar

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carb only costs $16 on ebay, buy a new one

cant tell you how many hours i wasted chasing surging issues with carbs and some never work right no matter how clean you "think" they are

all i can imagine is there are certain crevasses in the internal tiny passages you cant get to that get clogged and you just cant get it all out
 

slomo

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carb only costs $16 on ebay, buy a new one

cant tell you how many hours i wasted chasing surging issues with carbs and some never work right no matter how clean you "think" they are

all i can imagine is there are certain crevasses in the internal tiny passages you cant get to that get clogged and you just cant get it all out
Yup, sometimes it's much easier to get a fleabay carb and call it a day. Just make sure the linkages will line up before buying. I've had good luck with them, so far.

slomo
 

Hammermechanicman

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carb only costs $16 on ebay, buy a new one

cant tell you how many hours i wasted chasing surging issues with carbs and some never work right no matter how clean you "think" they are

all i can imagine is there are certain crevasses in the internal tiny passages you cant get to that get clogged and you just cant get it all out
Lots of carbs have tiny passages for fuel and air in the idle circuits. Many times only way to clean them is an ultrasonic cleaner. On some carbs there are passages that were plugged after drilling. Can't run a wire cleaner through them.
 

slow030

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Removed the idle screw and cleaned carb again, no change. Had ordered a ebay carb a week ago just in case, came today, put it on ran worse than the original carb. So, I picked up a used nikki carb from a friend that was dumping gas out of it, swapped my needle and gaskets from my original carb , and that worked, runs good with no surging or popping. Hopefully that takes care of motor and I can see if it will mow. Thanks for advice
 

keakar

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Removed the idle screw and cleaned carb again, no change. Had ordered a ebay carb a week ago just in case, came today, put it on ran worse than the original carb. So, I picked up a used nikki carb from a friend that was dumping gas out of it, swapped my needle and gaskets from my original carb , and that worked, runs good with no surging or popping. Hopefully that takes care of motor and I can see if it will mow. Thanks for advice
thats the great thing about ebay, easy no hassle returns

not great when you get a bad one though and you have to wait on another one.

good thing you got lucky to find a good spare to rebuild
 

slomo

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Wonder if the poor running ones needed a pilot screw adjustment? Float level adjustments?

I soak a carb in Diesel all night. Then the next day clean all the tiny holes out with a nylon bristle. Scrub it down with the ex-wife's tooth brush. Spray carb cleaner both ways on every orfice wearing safety glasses. Then blow out with a real air compressor and blow gun both ways. If they are really bad, put them in the wife's dishwasher.

slomo
 
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