toddk042

iTrader: (1)

I have a 1979 with a nikki on it. I decided to rebuild the carb because it would would stall if I let it go below 1200 and was really rough. Also, when watching the spray pattern in the primaries, the front was nice and fine, but the rear did not output anything until I really throttled it, and then it came out in dribbles, not a mist.
So, I rebuilt it over the holiday weekend. Wow, there was so much crap in the jets. (It should be noted that I had to replace the gas tank as it has completely rusted out).
Many of the holes in the jets were completely clogged.
I primarily used the Web page titled "Rebuilding the RX-7's Nikki Carb". I also had the Haynes manual, and the fsm.
when removing and bolt or jet, I taped it to a diagram so I would not get them mixed up.
I got it back on the car tonight, got everything hooked up. Turned the car to the on position, the bowls filled to the correct level, no leaking gas that I can see.
I Pulled the choke and started it up. It caught immediately, and went straight up to 5500. The coolant, gen, and add oil lights did not go out (the did before the rebuild). This surprised me, so I immediately shut it down. I checked the oil level, and I put a little oil down the secondaries by manually opening them and pored a.little in both. I let that make its way down for a minute, then started it back up, this time without the choke (I forgot to pull it). It fired right up, and went to 4500 and just stayed there. The coolant gen and add oil lights stayed on. Nervously, I let it run until the temp needle moved, but the lights did not go out, so I shut it down. While it was running at."idle" I saw nothing from the venturis, when I rev'ed it, both the front and back now come out as a fine mist like quality.

If you've read this far, thanks. I'm needing some advice on next steps.
I have a hunch the PO may have adjusted the idle to compensate, so I'm thinking I need to close the air and idle mixture screws to bring down the idle. Thoughts?
Any ideas on the idiot lights staying on?

​​​​

​

​​​​

toddk042

iTrader: (1)

Oh, I did check the throttle cable, and it is loose (when not stepping on the gas). I also checked the the hot start cable, and it seemed taught, so I removed it temporarily, and that did not help

toddk042

iTrader: (1)

I found this post Bad Alt Causes Idiot lights, so I need to do some testing there too. Maybe something came loose when messing with the connectors on the carb. That thread has ideas on how to test the alt.
I need to pick up a tach to make sure I'm seeing the correct rpms. It does not seem like it's actually that high

NCross

iTrader: (18)

toddk042

iTrader: (1)

Agreed. I think I'm getting a misreading on the Tach do to a possible regulator or Alternator failure. I just picked up a cheap multi-meter that includes a hertz counter. I'm going to use it to determine what the real rpm is by taking a reading off the coil negative terminal. Should be two blips on it per rotation (Rotor Speed to shaft speed). The readout is in hertz (number of blips per second), so multiple the number on the meter by 30 should get me rpm.
1r = 2blips; rpm / 60 = rps; 2rps = number of blips per second
RPM Hertz on Meter4000 => 132
3000 => 100
2000 => 67
1000 => 34
750 => 25

toddk042

iTrader: (1)

The carb is acting much better. The secondaries were not completely closed, causing the 3k idle. I manually worked them and gave them a shot of carb cleaner it calmed down.
It is still idles 1k -1250, but it would not do that before.

toddk042

iTrader: (1)

The carb is acting much better. The secondaries were not completely closed, causing the 3k idle. I manually worked them and gave them a shot of carb cleaner it calmed down. <br />It is still idles 1k -1250, but it would not do that before.

NCross

iTrader: (18)

Tach signal comes from the trailing coil, thats most likely why the gauge read 5000 RPM, or rather 14 volts.