Took apart the pump stacks. Inlet needles definitely not stuck. Some of the flapper valve fingers were not sitting down nicely - some were standing up as high as about .035". I think that was the problem.
Where can I get Mikuni rebuild kits?
Hard starting with Mikunis
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ted johnson
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Re: Hard starting with Mikunis
LAD Specialties, Comet Kart Sales, EC Distributors, several others. Look at REAR's resources.
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Jeff Campbell
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Re: Hard starting with Mikunis
..when you say it is not pumping, do you mean it isn't pulling the fuel up the fuel line (the air in the line isn't getting sucked into the carb, with the fuel coming in behind it)? ... or are you saying the fuel line is full of fuel, but little or none is going from the carb into the carb throat?
Jeff
Jeff
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Brian Thomas
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Re: Hard starting with Mikunis
Just a long shot ,,, you dont have a screen/sock type filter on the pet cock on the fuel tank do you ? I have seen those plug and it wont pull fuel from the tank . I just tear them off .
Brian
Brian
Brian , Dottie and Shadow Thomas
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philrock
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Re: Hard starting with Mikunis
Jeff, it isn't pulling the fuel up the fuel line - the air in the line isn't getting sucked into the carb, with the fuel coming in behind it.
Brian, I don't have that kind of petcock.
Brian, I don't have that kind of petcock.
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ted johnson
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Re: Hard starting with Mikunis
Get a new diaphragm kit, disassemble the carb and clean each piece and blow it out, making certain the inlet needle rattles freely when the fulcrum arm is held down. Make sure the fulcrum arm is flush with the inside surface of the body. Assemble with new diaphragms and gaskets per the attached diagram, making sure all the holes and plate pins are properly aligned. Set the high speed needle at about 1-1/4 turns, and the low speed needle at about 3/4 to 1 turn. Be CERTAIN 
that the pulse path is clear, and no less than 1/8" in diameter. .141 is better. Be sure the pulse hole in the gasket is aligned with carb and manifold. If the reeds are seating, and the fuel hose is bclear, the carb should pump just fine. I tried opening the attached PDF, and it wouldn't open until I saved it off, then opened it. Sorry. TJ
that the pulse path is clear, and no less than 1/8" in diameter. .141 is better. Be sure the pulse hole in the gasket is aligned with carb and manifold. If the reeds are seating, and the fuel hose is bclear, the carb should pump just fine. I tried opening the attached PDF, and it wouldn't open until I saved it off, then opened it. Sorry. TJ- Attachments
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- bc34_stack.pdf
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