Dave-ger

Before I say anything more, I've been doing some searching to figure out my problem.

something to note before I describe the entirety of my problem:

This link has me thinking that my floats could have been adjusted wrong and/or un-necessarily adjusted, since the top of my carb is off another carb. but I doubt that part got messed with... the other possibility is the piece of wizardry that was near the oil lines (removed, I run pre-mix), but I just don't know.

https://www.rx7club.com/1st-gen-archive-71/intake-carburetor-troubleshooting-flooding-problems-238029/


Anyways, I have a 12A out of an 83 RX7 with a Nikki carb that was rebuilt 2 or 3 years ago ish. the emissions and oil injection are removed from the engine. even during the first few months of running it, and still today, it will often flood out if I drive my car in a rough manner. Usually cornering hard with bumpyness, or even driving a bit obnoxiously on a smooth surface. what I have finally discovered is that the floats are sticking when it floods out like this. I usually have to shut the car off real quick, get out and hit the float bowls with a hammer, then crank the starter with my foot to the floor to get it the car running again. I'm stumped, and frustrated enough to try a holley... if only it wasn't for the cost.

Does anyone have any insight I may have missed? that would be much appreciated.


Also, I read that a fuel pump with too much pressure could cause flooding. I don't think it could do what my car is doing, but it's a thought. My fuel pump is rated for 5 psi, and according to the crappy spectre gauge I used for a short time, it put out about 4 PSI.

anyways, any insight is very welcome. thanks

sino305

I'm not too sure how much help I can be, and anybody correct me if i say something stupid, but, if you have a pressure gauge you most likely have an after market fuel pump, which could be causing flooding if your running a Nikki not tuned properly, that also depends on engine mods, if any.
Also, as far as a Holley 465. My recommendation is to not go with it..ive had it and was not happy with it whatsoever.

Kentetsu

Check this: http://www.nellump.net/peri/epi/firs...odedCarbs.html


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Dave-ger

I wish I would have checked this sooner. I just looked up what the vent solenoid was, and I didn't even have mine hooked up!

So that was probably the whole problem, and I greatly appreciate the help with that. Unfortunately I've already bought a new holley 465 and I'm in the process of adapting it to my car. I'm almost there too. I guess I'll just proceed with the holley swap. The good news is that it's the kind of carb that I can do just about anything with and it will simplify my engine bay quite a bit, which will look really slick. I'm hoping to get more throttle response and a bit more power too. I know a lot of people who are good with these carbs, so that's good news too.


Well, hopefully my holley works out. If it does, my Nikki will be much more sellable than I thought, since I'm now 99% sure it was just the solenoid.

oh yea, I need to put my expansion tank back on my fuel tank setup. My fuel cell expands a bit now that I have a charcoal canister again, that article said that doesn't help either.


Anyways, just for fun, here's my mock up of my new carb setup. I'm adding another 1" carb spacer to get the carb up and away from my big ford alternator and possibly spacing up the air cleaner since I can get a spacer for free from a friend, and I have the room.

cfamilyfix

iTrader: (15)

hmmm...holley on a nikki manifold. how does that work?

Dave-ger

made an adapter out of a carb spacer. this is a mock up without the modified stock spacer below:




I hope it works!

cfamilyfix

iTrader: (15)

nice! good luck with it!

Dave-ger

Thank you. I'm nervous and excited about it at the same time.

This is how it's going to fit, just dialing in a few more things:






I'm not terribly happy with the PCV valve I purchased, but I'm pretty sure it will get the job done.


checklist of things to do before I'm ready to get fuel to the carb and attempt starting it:

get a new "T" for my vacuum advance on my ignition as well as more vacuum line (broke my old T )
get rid of my return line
figure out my throttle bracketry (was going to add a piece so I could simply pull from the bottom instead of the top, making the throttle cable location okay, but I can't drill through the holley linkage, it's gangster hard!)
either get a hot choke stove kit or convert to an electric or manual choke
install a fitting on my air cleaner for the other oil vent dealie

and I think that's about it. A friend of mine said he'd help me tune the carb, if the jets it has in it work, then I'm sure he'll get my car running better than ever.


PS I really need to get rid of that god awful water cooled oil cooler. it's really ugly.

Dave-ger

the new carb works beautifully. I do have a couple problems. because of how I installed the stock carb spacer, I had a horrible vacuum leak, but I fixed that by eliminating that piece, cleaned up the look of the bay a bit as well.


I also have the idle turned all the way down. I need to drive it more and remember where it idles now, (was 1300-1400 with the vacuum leak) and possibly check for more vacuum leaks if it's still too high. since my idle is turned all the way down, is it possible that I need to change the jets up a bit? it does seem to run cleaner than ever as it is though, so it doesn't seem too rich, it also doesn't backfire on a high RPM downshift, so I'd imagine that it's not lean (I have experienced backfire from lean running engines)

I couldn't believe it though, my off the shelf holley 465 works better than my Nikki ever did in every department. the fuel consumption seems the same or better, and I don't have a dead spot in the throttle when I really get on it, and my low end power is though the roof compared to before.

I highly recommend this modification.

2ndgenotstock

Can I ask about the adaptor? Did you modify the Nikki manifold as in the first picture.. If so why. I'm thinking of swapping my Nikki to Holley. I'm having the same problem you did as my solenoid isn't hooked up. I'll jumper it tomorrow to see if it fixes it. If you have any better pictures could you help me out on this?