Hey guys,
I got a 83 rx-7 GX
rebuilt my carb. And I must say thanks to all on the boards that showed exactly how to rebuild a Nikki carb. No problems at all, was easy.
The only thing I'm having problems with, Is I think the carb needs small adjustments. But the Nikki carb from as far back as I can rem has this Metal Cap over the air and fuel adjustment screws. I have tried everything to get this cap off. Or does it come off. Does anyone know what this cap is. Or is there some kind of push or pull adjustment with this metal cap.
Any Help would be appreciated.

Thanks

MDK

 

You'll most likely need to pry it off with a screwdriver. Once it comes off do yourself a favor and throw the cap away. I cant remember if its in the FAQ or not (most likely is) but look for a thread that is started by the member Sterling and called something like How to adjust your nikki. Its something along those lines. It will get you on the right path to getting it set right.

Good luck.

 

That cap is a soft alloy that was squeezed onto the idle mixture screw 7s headed for the US in 84 & 85. It kept the mixture exact so that it was rich enough to produce burnable exhaust gases, but not so rich that it would soot the complex emissions system all up.
Pry it up a little on all sides, and pull straight out as much as you can so you do not bend the top of the mixture screw beneath it.

 

I thought I had tried that technique. But I will try it again. It's like a kids safety cap, need a kid to get into it. I could see the cap was squeezed around the screws when the carb was out and being rebuilt. But there was no way I could safely remove the cap. Car seems to be running very rich since the rebuild and I'm wondering when I was trying to get that cap off if I didn't turn the screws or something?

Thanks.

 

By "Running rich", are you talking about overall, or just at idle? The only thing you can change the mixture of with that screw is the idle.

 

I would have to say overall, but when she is idleing it is still very rich. You can really smell it. I've had the car since 86, and she has never had such a gasy smell. That's why I was thinking the mixture must be a bit out. Not sure what else it could be? Car runs fine otherwise.
Maybe I should just take her and let Mazda do a real good tune up, make sure all the timing is correct and check everything out. It's just way to cold here to be doing stuff outside. Daytime high was -25 c . Freeze your gonads off. But I sure want to try and get that stupid cap off, or see if it will at least do what you suggested. Because you should be able to adjust it if you have to. Not like the Japanese to do things like this. NOW the big 3 I could see. Big 3 that's hallarious should be called the broke 3.