NCross

iTrader: (18)

I just recently sold my side draft carburetor in effort to either return the engine to the stock Nikki, or do a 13b EFI swap. So after doing a little bit of tuning and adjustments I got the car to start and hold idle relatively well.

A couple issues...

First issue I had was I had to set the idle sort of high and build a choke mechanism to get it to start and hold idle (choke linkage was broken, I had to repair it). I let it sit at 2,000RPM for a couple minutes so I could pull the choke out and rev it a bit. When I went to adjust the idle cam screw I noticed the rotor 2's exhaust manifold was glowing red. I lowered the idle to about 1,000 RPM and it stopped glowing.

It smoothed out to a very nice idle for a minute or two. So I revved it to 3-4,000 RPM a few times and it seemed pretty smooth and responsive with minimal pops and crackle sounds. I tried to rev it to 5-6,000 and it sort of hit a wall in between and didn't want to rev any higher. It gurgle and popped. By this time the thermostat had opened up and it was running warm. I assume there isn't enough fuel? Lean mixtures cause glowing manifolds correct?

The other issue is that I put it into 1st gear and did a little stroll across the yard (4 flat acres). It took off pretty decent, but when I got 30 feet or so out and shifted to 2nd at about 10mph it sputtered a lot and barely wanted to move. I turned around about 100 feet out and went back to the driveway. I let it sit and idle and I noticed it had a rough sparatic idle now. It idled at the same pace as a motor cycle at this time between 700-1000 RPM. When I tried to adjust the fuel mixture and idle screws it didn't affect the roughness, only the speed. When I got back in and tried to move the car again it kept wanting to stall out and wouldn't budge an inch. Also, now when I rev the car in neutral it stalls out.

Vashner

What manifold are you using? Stock intake? SA or FB (shutter valve)?

Secondary connected? (See FAQ they tend to slip off). If yes shutter valve
test shutter valve.

NCross

iTrader: (18)

FB manifold and 79 carb. Are the secondaries controlled by that link that slips onto the piece with the spring and black plastic cover? That was connected after reading about it here.

bliffle

Sounds like it's erratic, from your description, so it MAY be crap in the fuel.

NCross

iTrader: (18)

Well I took reference from my spare FB carburetor. The mixture screw still had the cap tapped on it from the factory so I figured it was tuned to spec. I noticed that it turned inward 6 times before stopping. On the SA Nikki carburetor I turned the mixture screw all the way in and turned it out 6 times. It runs much better! I did however notice that maybe there was a clog...

When it was idling for a few minutes I sat it up at 2500RPM for about 30 seconds and it made some strange noises like there was a clog and the fuel pump wound down or a second and the RPM dropped to 2000 on its own then it went POOOF like there was pressure built up and shot to 4000 RPM. I let off the gas and it sat at about 1,200 RPM fairly steady and revs really easy and smooth.

I had it running for about 15 minutes just kind of blipping the throttle a couple thousand RPM to test it and drove it around the yard. Seemed much better. Note that the car is not registered and I don't want to drive it on the street and get into trouble.

I think I'm going to change the fuel filter again, buy some brand new factory plugs (I'm running the NGK 9's the previous owner had in it) and put another 2-3 gallons of gas in it and dump a bottle of seafoam in there and let it sit and idle for an hour or so blipping the throttle here and there.

BrianHeston

This sounds very similar to the first problem I had with my FB back in the day. It turned out to be bad needle valves in the carb. I had been told the carb had just been rebuilt, but it had sat so long without being run or driven that the tips had warped and it was actually flooding, not running lean. I could start it up and idle all day long, but once I drove about a half mile to a mile, it would sputter to a stop. It felt like it was running out of fuel, but it was actually drowning.

Try a rebuild kit on that old Nikki. If I'm right, you're all better If not, it's only $30 and probably should be done anyway.