Don't know how to explain it other than that if I give it beans before 2k RPM that it stalls...

If I ease on the gas up to 2k. It will momentarily stutter at 2K, then climb above... from there on out it responds to the throttle like it should.

As you could imagine, this makes daily driving a pain in the ***... Idle is solid at about 650 rpm so I don't believe it's a vacuum leak, what else could cause this?

 

that is normal behaviour if you have mechanical secondaries, do a search on it for more info

 

secondaries are not mechanical... engine is in stock configuration with the exception that the belt to the air pump has been removed.

 

I've had a similiar issue for a long time myself. I just chalked it up to the carb and just shipped off a core that I had for a rebuild. Is this at all times or just when you start it up? Being in a cold area I'm sure it'll be a hell of a reaction when you first start it up as mine has been struggling with the morning 60s as of late on first start. You might wanna consider 2gdflids as that seemd to make worlds of difference for me. Good luck.

 

It's worse in the cold (30-40 degrees, what's 60?)

What is 2gdflids, how much does it cost, and how easy is it?

 

My 12A did that after I removed the emissions as well. I was told the stock carb wouldnt work without all the emissions equipment to support it, so I went to the aftermarket, which only made it more noticeable.

I would honestly have to say if it IS related to the carb, its not just as easy as rebuilding it, and if it isnt the carb, its almost certainly a vacuum leak somewhere.

 

Clogged primary transition circuit, most likely. Or a problem in the accel pump.

 

I'm about 1/4 the way through a tank that's got a can of seafoam in it... It has improved noticably but it's always been weak below 2k RPM. Is the accel pump an easy adjustment?

 

2gdflis, sorry dont know where that 2nd d came from. Its a mod where you replace the leading coil with a leading coil pack off of the 2nd gen. It frees up the dizzy and improves both throttle response and i've heard spark intensity as well. I've also heard that its considered an upgrade for the 3rd gens. My accel smoothed out quite a bit when I switched over although there are quite a few sceptics about the whole thing. I swapped it out and let a friend drive my car for the 2nd time that week and he kept asking me what I did since it responded so much better. Like I said, may or may not help you but it worked for me, just pull the coil out of a salvage yard car or buy one off of a forum member.

As for the accel pump, I'm assuming Divin is referring to a stuck check ball or possibly a clogged hole. Something a proper clean and rebuild would work out. But I'm no carb expert.

 

i had something similar to your problem happen with my 82 seven..
from the sounds of it, your problem is probly the carb. but before i bought mine the clutch slave had a poor rebuild job on it, and would leak pressure causing the clutch to engage when i didint want it to. just an idea if you cant find a for sure thing.

 

I agree. I had that problem for years. Made the car impossible to drive on cold winter days until it completely warmed up. Take it apart and clean EVERYTHING really well. Carb cleaner and a tooth brush. Also, it wouldn't hurt to replace all your vacuum lines and caps. They can form tiny cracks that don't cause a vacuum leak at idle, but can cause issues when under load. I had a vacuum cap that looked fine until I pulled it off and noticed I could see light through it when I squeezed it.

I really doubt it's an ignition problem. I was able to completely eliminate it with two different carbs and I never touched the ignition in any way. Haven't even changed the plugs. That reminds me... gotta do that soon

 

Like I said mine improved, still nowhere near fixed. I just sent a core that I got with an engine core to SR Race Engineering aka CobraStngSVT for a complete tear down and build up so I'm anticipating that highly.

 

It actually drives great completely cold while the choke is engaged and holding it at ~2500rpm

The 2K stumble happens even after a 25 mile drive to to work, i'm able to make it stall in the parking lot with just a blip of throttle.

 

My nikki did that too. Main reason I got it the hell out of engine bay =P

 

Bad floater in the carb.

Open your carb up and check it out to see if you have a floater thats broke off. Happened to me.

 

Yeah; a clogged passage, or dirty or stuck check ball will cause a weak shot from the accel pump.

 

You guys are missing vital clues, read his posts again and see if you can find them.

You're going to need to pull the primary fuel jets and clear a bit of junk out of them. This can be done with the carb on the car, through the inspection caps on the bowls. Search "wooden toothpick" for the procedure.



.

 

I am intrigued...


Edit: I looked up your procedure... it seems interesting... Can anyone provide some pictures to at least get me going in the right direction?

I'm new to carbs, and I'm pretty stupid when it comes to actually working on things. Though I completely understand HOW they work.

 

Great Scott... BEANS! I didn't even realize that he said he gave it beans! You can't put beans in the carburetor! It just won't work. Good thing you noticed that

Back into serious-mode... I take it you think his primary jets are clogged. I can see that being at least part of the problem. But if he "gave it beans" then the accel pump should be keeping it rich long enough for the secondaries to open. So I think there's more going on.

I wouldn't do this procedure with the carb on the car. For one, the bowls are going to be full of fuel. When you remove the caps, it's gonna be all down the side of your motor. Two, the bowl facing the rear is über-hard to get to with the carb on the car and all the linkage attached. Better off removing the whole thing and even pulling the air horn to completely clean out the bowls. There's a little hole in the bottom of one that feeds the accel pump. It acts like a clogged drain when there's crud down in the bowls. Some pics here: https://www.rx7club.com/1st-generation-specific-1979-1985-18/how-test-nikki-fuel-jets-without-rx-7-a-964299/

 

Thanks for making me laugh uncontrollably... I meant to pull a James May and say "give it the beans" but I neglected that definitive article...

Really though, is there somewhere I can just blast with carb cleaner and hope for the best? I'm not nearly competent enough to remove a carb and reinstall it in a day (daily driver.)

I do want to pull this engine and replace it with a built 13B but that's far down the road.

 

13B swap ftw. did it and never regretted it. Honestly though if you need to pull the carb and take it apart, a solid saturday is all you'll need. Are you driving it through out lovely winter? If not work on it then. Also where about in MN are you, I can always help you out

 

I'm in farmington, I work in Eagan... Will be driving through the winter... if my plan goes accordingly, I will be completely stripping her down to barebones in the spring

 

Yikes. I would drive mine but i dont want it to see salt, or to die when a pick up hits me lol. Best of luck though. I know guys who have done it with no problems. just hope youve got some good tires for it.

If you want, I have my stock nikki and manifold from my old 12a sitting in my garage. If you want it to learn on lemme know. I'll let it go for a real bargain since its doing me a whole lot of good. It ran my 12A just fine as well, who knows might solve your problems or atleast give you a second carb to rebuild as to not take your car out of running order

 

If you can take me up on the "my word is good" payment method... I'm PMing you... I'm flat broke for a while (otherwise I'd have rebuilt it by now.)

In the last month I've:

-Shipped GSL axle in from Canada
-Dealt with customs bullshit for that
-Paid a buddy to help me put the axle in
-While swapping axle spent a good afternoon/night burning out all the old bushings and putting in new ones with new shocks and springs in the rear
-had the buddy swap in the front shocks and springs (didn't have the cash for time to do the front bushings
-new OEM spec rear calipers for the rear, ones that came with the axle are shot


I'm completely ******* broke. I could spare you like $20 tops up front. In light of it, I will pay you back over time, if that works for you... You can ask user "john smack" he sent me the axle without even seeing a penny of my payment on faith, he was paid.

 

Oh I'm not worried about the money. Like i said, it's doing me no good. How does $50 for the intake and carb sound, whenever you have the cash, and I can deliver it to you as well if you wish