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Nikki Carb Issues

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Old Jan 21, 2016 | 02:28 PM
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PaulN94's Avatar
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From: Calgar, Alberta
AB Nikki Carb Issues

I apologize in advance if these are obvious questions or my terminology is incorrect. I knew absolutely nothing about carbs a week ago because I've never owned or worked on a car with a carb.

I pulled the Nikki carb off the car, cleaned it out and replaced the gaskets. I found that the needle was actually inserted the incorrect way (somehow?) but that aside after mounting the carb back into the car (1980 RX7) I experienced issues with the fuel levels in the float bowl flooding the carb so I adjusted the floats to the specs I found online but this didn't change anything. I managed to set them up after many, many tries so they stop flooding the carb but the fuel level is still very near full. Am I missing something? If it doesn't flood out the carb is there reason to change the fuel level?

The car runs now but is running at 3000-4000rpm and is running rich (smoking) and I am unsure how to set the carb up to safely drive around the block for further testing.
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Old Jan 24, 2016 | 12:23 AM
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Ricardio Frenz's Avatar
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From: Clemson, SC
Sounds like you may have an Air Bleed problem. Does the main look like it has been messed with? The same goes for the Needle. Are you sure it wasn't damaged or letting in unnecessary fuel? If the float isn't properly adjusted and the air bleed isn't working, you could end up with a siphon problem, leading to the float bowl filling up when it shouldn't (I think). Feel free to correct me on that, and good luck
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Old Jan 24, 2016 | 04:08 AM
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When you pulled the needle out of the seat, did it have the little spring loaded button still in it?

There should be a hole in one end of the needle (where the spring and the button should be) and a pointy end on the other, this end goes in first.

If the button and spring is missing or needle is in upside down this will cause unusually high float levels.
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Old Jan 24, 2016 | 01:58 PM
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PaulN94's Avatar
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From: Calgar, Alberta
Originally Posted by Ricardio Frenz
Sounds like you may have an Air Bleed problem. Does the main look like it has been messed with? The same goes for the Needle. Are you sure it wasn't damaged or letting in unnecessary fuel? If the float isn't properly adjusted and the air bleed isn't working, you could end up with a siphon problem, leading to the float bowl filling up when it shouldn't (I think). Feel free to correct me on that, and good luck
I'll have a look into that. Would that be causing it to idle at over 3000? It doesn't seem to want to go lower than that and will rev up past 4200 when I'm not touching it. I've had it climb to 4500 before I managed to run to it and shut off the ignition. I noticed a large amount of oil coming from the oil pan last time I ran it that I'll have to change the gasket before I run it any further.
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Old Jan 24, 2016 | 02:15 PM
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From: Calgar, Alberta
Originally Posted by sir revalot
When you pulled the needle out of the seat, did it have the little spring loaded button still in it?

There should be a hole in one end of the needle (where the spring and the button should be) and a pointy end on the other, this end goes in first.

If the button and spring is missing or needle is in upside down this will cause unusually high float levels.
Yes the needle had both the spring and the pin in it when I pulled it apart and replaced it. Apparently it ran with the needle being inserted the opposite way! I don't know how that would seal. When I was playing with the float levels it seemed like it was either either completely sealed or flooding out the carb until I found an in between setting but it stills idles really high
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Old Jan 24, 2016 | 04:39 PM
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From: Clearlake
Originally Posted by PaulN94
Yes the needle had both the spring and the pin in it when I pulled it apart and replaced it. Apparently it ran with the needle being inserted the opposite way! I don't know how that would seal. When I was playing with the float levels it seemed like it was either either completely sealed or flooding out the carb until I found an in between setting but it stills idles really high
If you used the new needles an seats in a gasket kit there usually garbage an could be your flooding problem, either use the originals if there still good, or order JUST needles an seats from Mazdatrix. I had a similar problem an had to do a re-rebuild lol solved the flooding for me.
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Old Jan 24, 2016 | 05:28 PM
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From: Calgar, Alberta
Originally Posted by shamus massingale
If you used the new needles an seats in a gasket kit there usually garbage an could be your flooding problem, either use the originals if there still good, or order JUST needles an seats from Mazdatrix. I had a similar problem an had to do a re-rebuild lol solved the flooding for me.
Good to know! Haha those re-rebuilds are fun hey? I guess I'm ordering some new ones from Mazdatrix and replacing the ones I got from that gasket kit. Thanks for sharing that as I would've never thought that could be the issue.
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Old Jan 24, 2016 | 10:40 PM
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From: Perth Australia
If it's still idling high, check the linkages and that the secondary butterflies are completely closed. Sometimes they can jam open a fraction..
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