Almost have the car back but after a rebuild he is saying that he has to go back in because the second chamber is not opening up( what ever that means) basically the car idels fine but when the RPM hits about 3-4k it bogs. He told me it might be a bad diaphragm or something about suction. does anyone know if he's on the right track. as far as checking the 2nd chamber and why it is not opening? i hope im making somewhat sense.

 

you mean your secondaries? Clogged Transition circuit maybe?

 

He's talking about the secondary butterflies. Unless the carb has been modified, they are vacuum operated (suction). It would cause the car to bog at high RPM as he suggested. It's possible that the diaphragm is torn/worn out, or that it's just not hooked up correctly. Most likely #2. You can also work around (read: Bandaid) the problem by performing the mechanical secondary mod. A search in the first gen section will give you more info than you'll ever want on that. It's really easy to do.

I have my secondaries rigged mechanically and I'll never go back. They open exactly when I want them to and they open completely - no question, and not much to fail.

 

definitely the secondarys

 

you guys are awesome. lloking up what the mod is. Should i have him just go ahead and find a new diaphram if that is the problem or mod it? anyone have one? thanks again guys

also just adde=ing this link with the mod just incase others find this later.
https://www.rx7club.com/showthread.p...al+secondaries

 

I'm not aware of anywhere you can get the vacuum secondary diaphragm anymore. It doesn't come with the rebuild kit, or at least not the GP Sorensen kits I always buy. Hopefully he just has the vacuum lines hooked up wrong. It happens, especially if all the emissions stuff is still intact. It's entirely up to you on whether or not you want to mod it or not. There are people that prefer the vacuum secondaries. I myself prefer mechanical.

 

This thread:
https://www.rx7club.com/1st-generation-specific-1979-1985-18/common-cause-power-loss-nikki-carbureted-models-632007/


Will probably be the solution... It was for me, drove the car for 2 months before I knew of this... it was like a whole new car when I hooked it back up.

 

Yeah def check the dumb teeter totter.. That thing sucks when it comes off.

 

The mech. is suppose to be the best in this area and after talking with countless people i think he is right. i just wish i had the car back. bought it about 2-3 weeks ago and never took it home. should of brought it to a mechanic before buying it......

 

if for some reason you want to stay with vacuum I have some spare secondary diaphragms (used). I'll send you one for free.

 

Go with mechanical secondaries to solve the problem quickly

 

the diaphragm is easy to get to (4 screws) check it to see if its even the problem... Teeter totter being unengaged could be ur issue as well because it doesent allow the throttle linkage to open the secondaries all the way.

 

Forgot about that damn teeter totter, good call.

 

Update turned out to be the diaphragm.