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-   -   Nikki Questions, needle/seat and more (https://www.rx7club.com/1st-generation-specific-1979-1985-18/nikki-questions-needle-seat-more-1109178/)

redlightrich 01-05-17 08:57 PM

Nikki Questions, needle/seat and more
 
Hello all, due to the fact that my car is a 29k mile car ( 79SA) , and very original, I have decided to keep modifications to a minimum. I will do my best to keep it running as intended until a later date. I have a Racing Beat exhaust, that I have put to the side. I am keeping it stock.

Anyway, I have been experiencing a lack of power, and if I let it sit for any period of time, it would not start without a smack to the carb with a screwdriver. When I bought it, I was told the carb was rebuilt, which made me nervous.

Anyway, after a long while, I have decided to remove and disassemble the carb, to see what is going on. I found a large vacuum leak ( base screws were loose) and my accelerator pump spring was actually in there sideways!!! Yes, under the little diaphram, the spring was squashed in there vertically!! I was shocked that it would squirt at all, but it did. Just not the full volume.

Anyway, I decided to clean it up and check all passages, and unfortunately, someone before me already changed the needle and seat.

I can make them stick fully closed at will. I never had a flooding issue, so it isn't a matter of them not sealing. It is that when they fully seat, they won't release ( at least with the low pump pressure available). I have spent some time trying to locate New Old Stock originals, with no luck. These aftermarket seats are brass, with a hole in the middle. There appears to be NO taper at all to the seat. The needle's rubber tip simply plugs the little hole. The needles rubber tip is tapered.

Does anyone have any "tricks" that make these aftermarket needle/seats functional? I wonder if anyone has figured our an alternative or a different part that will work?

Also, in the float bowl in the rear bowl ( one closest to the firwall) there is a "valve" that is in the bowl vertically, between the 2 main jets in the bowl. What is the purpose of this jet?

I am hoping to be able to get this car running respectably without removing all the emission equipment. I will disable a few items, but I would leave them in there to leave the visual alone, such as the hot start, and cold start, and maybe the bowl vent. I will be grateful for any guidance.


Happy New Year

Rich

t_g_farrell 01-06-17 02:37 PM

Take the needles out and burnish them lightly on the corners all around. The new needles and
seats are too rough and grab at certain levels/angles as they slide up and down.

redlightrich 01-07-17 08:03 PM

Thank you for that information. I also noticed that the new needles and seats have the tiny wire that attaches to the needle and to the float and makes the needle drop with the float. This wire allows the float to "pull it down" as the level drops.

These wire clips were not used by whoever did the rebuild on my carb prior to me buying the car. Actually, I don't know if they were included in older kits at all. I have seen this wire used on many different carbs in the past so it does make sense.

Thank you

Rich

t_g_farrell 01-08-17 06:11 AM

Whoever did your carb earlier screwed up. Double check all the details, there's probably other @$!#ups in it.


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