(02/24/25)
Hey everyone, I recently got a 1981 and the person I got it from had the carburetor out and disassembled already with the pieces in a box in the car. Most are clean already (could use brushing though).

From what I've gathered from the pieces, it's the OEM Nikki 4 barrel for the 12A rotary. I can't identify it for sure though, the numbers I've been able to find are N201-1E11 and another one I can't remember as the part isn't on me right now but I can get that, but it's the same format of N2 something. I haven't been able to get anything from those numbers though.

I'm a total noob, this is the first carb I've ever heald. I (mostly) understand the operation after reading the first Gen carb manual to pretty much completion. I plan on rebuilding it since I had the air horn, carb body with the Nikki logo (no other numbers on it annoyingly), and the throttle body which still needs cleaning (unsure if there is a number on it as of now).

Below are the pictures of the component I can't identify on the 1979-1985 carburetor manual I grabbed from Foxed.ca.

Bottom view(?)


Front (?)





Any help with this carb would really be appreciated. My next move after I identify the pieces is to find out what rebuild kit I should purchase then put it in the car.

Follow this thread if you want as I continue to try and identify pieces after they are cleaned. When I get home tonight I will update this thread with more pictures of the main components. One thing I also haven't found for sure is the Bowl so that'll be a fun replacement if I don't have it, might doom things. Let me know if my speculation is true.

Thanks!
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That is the choke return diaphragm. Here is the Mazda 1979-1985 carb manual. https://www.foxed.ca/rx7manual/manua...01979-1985.pdf

You'll find a lot more factory manuals free here: https://www.foxed.ca/index.php?page=rx7manual#firstgen

 

Show us what you have and we can help identify it. If this is the exact carb that came off the car and is just in pieces in the box, that should be an easy DIY to get it all back together and working. The thing is, if the previous owner swap the carb or the base plate for some reason, things could get squirrelly. Pics will help a lot.

 

I plan on taking more pictures today of the pieces in the box since it's my day off work, I think so far I have all of the pieces except for a few screws and things but that part I imagine would be easy to just find replacements.

Thank you guys so much for help identifying things, this place is amazing!

 

I want this thread to be a record of identification for others trying to start and learn the same way I am, thank you everyone for helping me with this and for helping people in the future with their rebuilds.

I welcome everyone to also put in tips, tricks, tools that work well for sticky situations, brands or products, methods, anything you think was helpful to your experience!

Please help me in the quest of identifying ever piece of this carb and helping me find out if I can rebuild this OEM Nikki carb on my 1981 rx7.
Few questions first:

What rebuild kit should I use? I've looked around other forums and I have on in mind but I think more advice the better!
If I don't have all of the bolts, screws, washers, etc would those come with the kit or would that be a "Dang it I need to buy this single screw and this single bolt" situation?

Here are all of the pictures of every piece that I found inside of the box that I was told held the carb. I don't believe every piece is the carb to be honest. The rest of the things in the box are random bolts, screws, old crappy gaskets, and whatever else. In total I have 19 parts that I would like some help with. I know a few, the ones I do know I'll put a label under the photo but they are mainly there to show what I have and don't have for the car from what he claimed.

Part 1: Not sure

Part 1: Not sure

Part 1: Not sure

Part 1: Not sure

Part 2: Carb body

Part 2: Carb body

Part 2: Carb body

Part 2: Carb body

Part 3: Air horn

Part 3: Air horn

Part 3: Air horn

Part 3: Air horn

I can only upload 12 images at a time so this will be a bit

 

Part 4: Unknown plastic piece

Part 4: Unknown plastic piece

Part 4: Unknown plastic piece

Part 4: Unknown plastic piece

Part 5: Throttle body

Part 5: Throttle body

Part 5: Throttle body

Part 5: Throttle body

Part 6: Not sure

Part 6: Not sure

Part 6: Not sure

Part 6: Not sure

 

Part 7: Unknown sensor, assuming inductive?

Part 7: Unknown sensor, assuming inductive?

Part 7: Unknown sensor, assuming inductive?

Part 7: Unknown sensor, assuming inductive?

Part 8: Pretty sure this is the needle

Part 8: Pretty sure this is the needle

Part 8: Pretty sure this is the needle

Part 8: Pretty sure this is the needle

Part 9: Unknown bracket, not sure what it fits on or what fits on it

Part 9: Unknown bracket, not sure what it fits on or what fits on it

Part 9: Unknown bracket, not sure what it fits on or what fits on it

Part 9: Unknown bracket, not sure what it fits on or what fits on it

 

Part 10: Floats (two floats, is that normal with other carbs?)

Part 10: Floats (two floats, is that normal with other carbs?)

Part 10: Floats (two floats, is that normal with other carbs?)

Part 10: Floats (two floats, is that normal with other carbs?)

Part 11: Not sure

Part 11: Not sure

Part 11: Not sure

Part 11: Not sure

Part 12: Secondary Diaphram Assembly

Part 12: Secondary Diaphram Assembly

Part 12: Secondary Diaphram Assembly

Part 12: Secondary Diaphram Assembly

 

Part 13: Not sure

Part 13: Not sure

Part 13: Not sure

Part 13: Not sure

Part 14: High Altitude Componsator

Part 14: High Altitude Componsator

Part 14: High Altitude Componsator

Part 14: High Altitude Componsator

Part 15: Accelorator pump diaphram

Part 15: Accelorator pump diaphram

Part 15: Accelorator pump diaphram

Part 15: Accelorator pump diaphram

 

Part 16: Not sure

Part 16: Not sure

Part 16: Not sure

Part 16: Not sure

Part 17: Unknown bracket, not sure what it fits onto or what fits onto it

Part 17: Unknown bracket, not sure what it fits onto or what fits onto it

Part 17: Unknown bracket, not sure what it fits onto or what fits onto it

Part 17: Unknown bracket, not sure what it fits onto or what fits onto it

Part 18: Not sure what this is but it looks too big to be on a carb. But it was in the box so it goes into the thread

Part 18: Not sure what this is but it looks too big to be on a carb. But it was in the box so it goes into the thread

Part 18: Not sure what this is but it looks too big to be on a carb. But it was in the box so it goes into the thread

Part 18: Not sure what this is but it looks too big to be on a carb. But it was in the box so it goes into the thread

The only part left out is the Choke Diaphram because that was the first part on the thread.
Any advice on what these parts are on the nikki carb, what pieces I am missing, and how to place them back together if I can rebuild it using the kit and the 79' - 85' manual (among other resources).

I do have the blue carb cover and I can buy new filters for it in case anyone was wondering.

 

Update 2/25/25
After looking at the manual for awhile I have identified some pieces, I will update everything tomorrow. One piece I did identify is the accelerator diaphram and I found the accelerator diaphram cover on the floor of the car thankfully. I will add the accelerator diaphram cover to the thread pictures as well tomorrow.

One question if anyone knows, is the return spring for that diaphram supposed to be smaller than the middle section where it is or am I just using the wrong spring?

 

Was going to suggest that you look at the carb manual and compare. It has a complete breakdown of parts with detailed illustrations. Part 4 is the phenolic spacer that fits under the carb between it and the intake manifold. Part 18 is the ACV (Air Control Valve) part of the emissions equipment that mounts to the right (exhaust) side of the engine.

 

You have what looks like all the pieces to remake that carb into a running example. You have to choose full OEM (using a the OEM rats nest and electrical harness) or stripped down nikki with possible mods. You should get a good repair manual or download the FSM to help you with reassembly and testing. If you can find an old Haynes manual, its one of my gotos along with the FSM.

 

I mistakenly posted 2 replies to this thread in the "Need help identifying this carb" thread with images which may help you identify the parts and how they go together.

 

I will look up the Haynes manuals! I think I have every piece except for a few bolts so I'll have to research what kind of bolt or screw goes where. Do you know what manual might go into that much detail?
The Carb manual I grabbed from foxed.ca only has the screw numbers for identification but you can probably see how that's not really helpful here lol.

 

Awesome and thank you! I will check it out. I'll probably poke in with a reply asking for kit ideas, I was looking at the Hygrade rebuild kit because while I have the still have I think all of the jets in the carb body amazingly I'm unsure how well they'd actually hold up. Do you have any resources on what makes a good jet and a bad jet? All the usual "look for cracks and make sure you can see through it" stuff I'm sure but size wise with calipers or something?

 

Part 20: Accelerator Diaphram Shell

Part 20: Accelerator Diaphram Shell

Part 20: Accelerator Diaphram Shell

Part 20: Accelerator Diaphram Shell

 

Thank you! I've been using this manual as well to find things and I am slowly updating the list. So far we are up to twenty parts because I found the Accel diaphram shell in the back of the car. I somehow found it within like 10 seconds of being in the car with all of the misc bolts, screws, and other related mess

 

Fearing I would mix up the screws, I measured the thread length from the bottom of the lock washer top of the head to the end of the thread. Good for relative sizes.
I referenced each to it's location.

 

Get some Snack size baggies.
The bleeds and jets are different for the primary and secondaries. However, you have matching pairs for the primary and the secondaries, for the two rotors. Put all the primaries in one baggie and all the secondaies in another.
The illustration in the Mazda Carburetor Manual is a good visual reference.
Also if you refernce page 63 of the same document, there is a chart for fuel jets and air bleeds specifications. I heard that the secondaries have larger holes than the primaries, true except for the #2 Slow Air Bleed where the primary has the larger hole.

You have a 1984 or 85 manual transmission carb, based upon the #2 Main Air Bleed in the air horn, and the Richer Solenoid (Part #8 in your pictures).

 

Dude what!! This is the best chart ever! Awesome stuff thank you!