I have a 700 double pumper it idles fine, but when I hit the brakes right after I let off the gas and push the clutch in it stalls. I never had this problem with my 600 with vacuum secondaries. The only thing different now is the carburetor and the manifold. I have a new booster, master, and comp cams vacuum canister. I thought the vacuum canister would fix the problem, but it didn't. I'm getting vacuum for the brakes from a knock out on my carb spacer that's right underneath the port on the baseplate.
The last third gen I had was non computer controlled also, I know with computer controlled cars it raises the idle if you push the clutch in while moving.
I also raised the idle just to try it, and with it around 900/1000 rpms it still stalls. I have the idle screws turned 1 & 1/4 turn out, and the secondaries open barely. thanks in advance
The last third gen I had was non computer controlled also, I know with computer controlled cars it raises the idle if you push the clutch in while moving.
I also raised the idle just to try it, and with it around 900/1000 rpms it still stalls. I have the idle screws turned 1 & 1/4 turn out, and the secondaries open barely. thanks in advance
five7kid
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May 4, 2026
Float levels where they should be?
Yes sir, but I will double check the float levels. I will try and test the reserve on the booster tomorrow. I wouldn't be able to hear if the booster was leaking vacuum over the exhaust. thanks
The float levels are on now. I found out the primary accelerator pump diaphragm is leaking when you go past 3/4 throttle. It wasn't adjusted properly. It still stalls when I slam on the brakes. I thought it was a fuel problem, but I found out you can't trust cheap liquid filled gauges, when it warms up it reads lower than when it's cold.
I have no idea where to go from here, other then to replace the diaphragm. I should've stuck with the other carb I had. This carb has been the biggest headache so far.
I'm going to go check the reserve on the booster now.
I have no idea where to go from here, other then to replace the diaphragm. I should've stuck with the other carb I had. This carb has been the biggest headache so far.
I'm going to go check the reserve on the booster now.
There is no reserve on the booster, it's got a lifetime warranty, i'm going to pull it and replace it.
It makes sense now, because I was wondering why I have the throttle adjusted barely open on the primary and secondary barrels and it revs high, now I know.
It makes sense now, because I was wondering why I have the throttle adjusted barely open on the primary and secondary barrels and it revs high, now I know.
I replaced the booster. Now it doesn't stall when braking hard, but it comes close. I might have air in the master/lines, I don't know what normal pedal travel is.