79Roxy

After troubleshooting some issues i was having before, I found that the most likely culprit was a bad accelerator pump. So i went ahead and rebuilt the carb on my 79. This is my first crack at anything like that and i thought i did everything right. However, with the carb reassembled and back on the manifold, I followed the haynes manual directions of plugging the idle compensator hose and trying to start it. No dice. The most it will do is fire up and run for about 2 or 3 seconds and then nothing. Took the plugs out and cleaned them and cranked it, didnt seem to be flooded. Could this be a mixture issue? Whats something i could try to troubleshoot? This is my only vehicle right now(mistake) so i need to get it running asap. Any help is appreciated.

Ta-Aikah

Does it run longer if you give it some throttle?

Are you using a choke?

79Roxy

Havent been trying to use choke. I found a vacuum leak at the back of the intake from where i removed a hose to install headers. After that it took longer to crank but ran a couple seconds longer. It let me give it throttle for a second once before i blocked the leak.

Ta-Aikah

Try the choke and see if it gets any better.

Giving it throttle and it dying makes me feel like it isn't getting enough fuel. Throttle adds air but there isn't fuel to make it work.

LEGALIZECHEY

iTrader: (1)

I had to poor some fuel down the carb while a friend cranked it to start my car. And that was the first time I rebuilt the nikki...

79Roxy

I found an ignition issue. I had to replace one of the points and now I have good spark all around. I had my dad come pour some fuel in the carb while i tried to start it. It didnt start that try, but the next time i tried it without him pouring fuel in, it started up with me pumping the throttle and it revved up to about 5k and I was able to feather the throttle and keep it alive around 4k for about 30-40 seconds before it died. I have good fuel pressure in the lines at the carb and both float levels look to be right about center in the windows. Any ideas?

79Roxy

Also, it still seems to do worse with choke.

Ta-Aikah

Where are your mixture and idle speed screws set at?

79Roxy

I put them back in with as close to the same number of turns as possible. Is there a way to check if they are in roughly the right spot?

Ta-Aikah

I hear most people start at 3 turns out from seated on the mixture screw and then a few turns after making contact on the idle speed, I believe. But if you're pretty sure you got them back where they were when it was running, I'd leave them alone for now.

If you look down the primaries of the carb with a flashlight, and work the throttle a little, do you see fuel spray from the accelerator pump nozzles between the primaries?

LEGALIZECHEY

iTrader: (1)

The carb manual on foxed.ca says 3-1/2 for mixture and 6-1/2 for idle. I turn both all the way in, Mark the top of the screw with a white dot, and count backwards from there....

79Roxy

I dont think it is. Would that mean the accelerator pump is bad? I just replaced it.

Ta-Aikah

It really doesn't shoot a lot of fuel. It's a small stream, but it should be a stream, nonetheless.

Was there a check ball and a small brass weight where each of the yellow circles are?

79Roxy

I didn't tear apart the main body. That was probably a bad choice.

Ta-Aikah

If there is an issue with the carb, that would be where it is, unfortunately.

If there really isn't any fuel shooting out of the accel pump circuit into the primary bores. There could be even more clogging going on.

Carb cleaner and compressed air will get the job done.

https://free-info-pages.com/rx7-rebu...r-yourself.htm

79Roxy

I appreciate the link, its pretty easy to follow. Issue: I cant get the check ball under the long skinny weight to come out no matter what i try. Any ideas? Could this be related to the issue?

Ta-Aikah

Are you sure there's a check ball in there? If it's stuck plugging a hole, it could definitely be part of the problem.

You might try soaking where the check ball is in the carb cleaner and see if that frees it up if there's one in there.

79Roxy

it looks like that was my issue. After a lot of persuasion i got the ball out and cleaned up the passages and it started up. Now Im just trying to figure out tuning it because it is way out of wack. Idles pretty low and a little lumpy.

Ta-Aikah

Glad to hear it's improving.

79Roxy

Does anyone know a good place to find an in depth guide to tuning the stock nikki? its idling at about 600 and doesnt seem to change much with the two adjustment screws. Pretty much every thread I find directs me to the old sterling site, which isn't around anymore.

LEGALIZECHEY

iTrader: (1)

I used this method, and it's a basic starting point for ANY carburetor
https://www.rx7club.com/1st-generati...e-carb-310927/

79Roxy

The Haynes manual says the larger screw above the mixture screw is the idle speed screw, but that doesn't seem to do anything. If the one under the throttle linkage is really the idle speed screw, whats the other one?

79Roxy

after looking at this thread
https://www.rx7club.com/1st-generati...-help-1132538/
it seems like I'm not supposed to mess with the one under the linkage... but the one above the mixture screw does little to nothing to the idle speed.

LEGALIZECHEY

iTrader: (1)

I'm not sure both mine have a vent there??

LEGALIZECHEY

iTrader: (1)

https://www.rx7club.com/1st-generation-specific-1979-1985-18/idle-wont-increase-846768/
https://www.rx7club.com/1st-generation-specific-1979-1985-18/1979-rx7-carb-help-1132538/

I just found this, looks like out of the two together, one is mix and one is air speed. The small one to the right under the linkage is your idle speed!