Changed throttle cable, dies when driving

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Otateral

Otateral

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The idle is good. But sometimes when I let off the brake and apply the accelerator, it dies. If I let off the brake, and don't apply any gas it seems fine, then I can press the accelerator and no problems.

Does this sound like a vacuum leak? I'm a newbie but I'm pretty sure the throttle cable is installed properly and is tight. The idle is perfect, otherwise. And it never dies while idling.
 
Carburetor operation and repair manuals and links to training movies and carb repair/modification threads are posted here for free download. Tune-up parts and technique suggestions in this thread.
 
Vacuum leak can cause off idle stumble, bog, or stalling depending how bad it is.

Need to know more such as year and model, dose this car have power brakes? If so the brake booster could be one cause of a vacuum leak. Disconnect power booster vacuum line from manifold, seal up power brake vacuum port in manifold, and test for stalling. If it stalls, it is time to rebuild, or replace power brake booster. If nothing changes, reassemble vacuum lines to booster, and look for other vacuum leaks.

Also a bad accelerator pump shot will cause a stumble or stall when throttle plate opens making a lean condition.

With engine off, remove air cleaner, look down into carburetor, and open throttle by hand. If accelerator pump is working properly a good strong shot of gas will squirt out. If just a dribble or no squirt is seen it is time for a carburetor rebuild.
 
Can anyone recommend a specific carb rebuild kit for 69 Plymouth Valiant, 3.7L slant 6? Preferably one at O'Reilly autoparts or Autozone, but Napa is okay too.
 
I would get a rebuild kit from Daytona Parts Co. They have a complete rebuild kit. Not just some of the parts thrown in a box. They helped with my rebuild on my BBD. I Needed mixing screws that did not come w/ kit from O rielly .Theirs does. They had them in stock at a reasonable cost. O'rielly could not even get them for my Obsolete old 6 cylinder. You get what you pay.
 
Another question, before I go down the road of rebuilding the carb... would using 87 octane gas cause these symptoms as well? I don't know why the thought hadn't crossed my mind before, but the stalling seems to have started up around the same time as when I filled it up for the first time with 87.
 
You could throw some Premium in and create your own custom blend. See if it helps but I don't think so. Didn't you say the problem really started with the new Cable install? Is it binding or sticking? If you can't find any vacuum leaks then It definitely sounds like a carb rebuild issue. Get a good kit as stated above and follow the steps.
 
Otateral said:
Another question, before I go down the road of rebuilding the carb... would using 87 octane gas cause these symptoms as well? I don't know why the thought hadn't crossed my mind before, but the stalling seems to have started up around the same time as when I filled it up for the first time with 87.
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i have ran all grades of gas through my BBD with no problems ever. these carbs are very easy to rebuild and get set-up. i just did one awhile back. just remember the check ball and the order you took it apart. lay all your pieces out as you go

make sure you have your idle screw set right

mine came from oriellys
 
Higher octane just burns slower to quell preignition in high compression motors. Doubt it will do anything in a 3.7 but empty your wallet faster.Look for a metal tag or stamped numbers on the carb to find the right kit.
 
OwdKasd said:
You could throw some Premium in and create your own custom blend. See if it helps but I don't think so. Didn't you say the problem really started with the new Cable install? Is it binding or sticking? If you can't find any vacuum leaks then It definitely sounds like a carb rebuild issue. Get a good kit as stated above and follow the steps.
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The accelerator stuck on me on my way home a while ago. I saw that the cable was very rusty and loose, so opted to replace it, believing that to be the cause. Later, the accelerator stuck again and that's when I noticed that there were 2 springs tangled together. My best guess is that the previous owner simply added a second spring when the first one became loose, and never removed the first one. 2's better than 1, right? Not.

I had only had the car about 3 days prior to this happening, so it may be that I simply hadn't had enough time with the car to notice the stalling problem.

Once the brakes are changed, I'll be getting a kit from Daytona and with the help of my brother, rebuilding the carb.
 
O_o

Decided to take a good look at the carb today and take some photos. What is this hose coming off the carb and leading to nowhere?

FYI this is a Holley 1920 on a slant 6 225. 69 plymouth valiant.

scaled.php
 
Dual springs are better or even prefferred. Its a safety issue. If one breaks your throttle will still return. I wouldnt run without two.Does the breather have a connection on the bottom for that hose?
 
Problem was the springs were side by side and getting caught with each other and locking the throttle open. For the hose, I'm lost on this. I see nowhere it could likely be connected to.
 
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