Hey guys, I've got a 1980 rx7 LS that's in pretty rough condition all around. I'm looking to see if any of you veterans with experience tinkering with nikkie carbs could give your $0.02 on what you think might be causing my issues

12A engine with nikkie carburetor (I believe her to be completely stock)

She will start. And run. Ilbeit 8/10 times you have to spray starting fluid into the carb.

Occasionally youll get lucky and it cranks right up. However upon doing so it will stumble and die unless you are holding throttle.

After about 2-5 minutes of holding throttle at 2k you can usually let off the gas and it will settle in around 1200-1500 rpm where it will stay and idle at. Ilbeit it will continue to fluctuate pretty randomly it is not a smooth continuous idle. it jumps around.

Sometimes you have to baby it because it might drop below 1000 which at that point she dies every time.

After you take her down the road and she's driven she's pretty solid idle wise and won't die on you.

However this is were the rest of the problems begin. Once you shut her off. and if you try to immediately restart her she will not start. No matter what. if you put a shot of starting fluid in her she will crank back up. But not on her own.

If you wait 5-10 minutes however and try to start her up (no starting fluid this time) she will usually start back up on her own.

It's kind of weird.

As far as I can tell she's stock? I didn't notice anything removed from the carb. It all looks pretty complete. she still has the "rats nest" as well.

Just looking to see where I should begin looking to resolve my idle issue / start up not holding idle on her own without help.

I should also mention that I've only really got experience with motorcycle carburetors and some other basic small block Chevy carbs so when I saw how complex this carburetor looked I was a little hesitant to dig into it

 

welcome to the board.

you can get a copy of the FSM here: Foxed.ca . if i recall, that site also has Nikki manual, it might be a good idea to copy that as well. the Nikki is actually not that bad to work with once you get used to it.

my first question to you is does the choke work?

i would probably say to start by checking for vacuum leaks. the idle is high and if the car won't tolerate a lower idle speed, then something is clearly wrong. be VERY thorough.

if you are satisfied with the vacuum situation, then i would go ahead and follow the procedures for setting idle mixture and idle speed.

if none of the above works, then report back and we can start looking at something more complex.

 

How absolutely fascinating. these manuals are a godsend!!

I'm completely in awe by the sheer amount of information in the carburetor manual thanks man!!

I'm away from home for the time being but when I get back I'll dig into it and see what I find. as far as weather my choke is working. The pull handle inside the car does work. When looking down the carb while pulling it closes but only about half way. there's a little device attached to the choke linkage with this spiral looking coil inside pushing on the linkage arm. I suspect that little device is supposed to push it the rest of the way but the spring inside seems to have lost its tension. as it moves easily.

my car back fires as well. Not when running. But after it's shutdown. Nearly every time.

I'll get back with you guys once I tear the carb down and see what I find thanks