Carb Guru's...need help
Thread Starter
Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
Carb Guru's...need help
I have an Edelbrock 1411 electric choke carb on a 383. There has been a chronic problem with the carb sticking. I accelerate, and when I let off the gas, it continues to accelerate (slowly) or maintains speed. When I push in the clutch, the rpm's shoot up to wherever the rpm's would have been if the accelerator was pushed to that level not under load (does that make sense?)If I give the pedal a quick stomp, it kicks back down. So it sounds like something is sticking.
I have checked the accelerator cable, and it operates smoothly. No sticking. The spring is fine too. I pulled the carb off, and the primary and secondary valves seem to operate smoothly. They seem to snap right back. There are no signs of anything rubbing.
Any ideas? Choke problem? Fast idle cam? I'm at a loss.
[Modified by 79MakoL82, 10:18 AM 9/13/2003]
I have checked the accelerator cable, and it operates smoothly. No sticking. The spring is fine too. I pulled the carb off, and the primary and secondary valves seem to operate smoothly. They seem to snap right back. There are no signs of anything rubbing.
Any ideas? Choke problem? Fast idle cam? I'm at a loss.
[Modified by 79MakoL82, 10:18 AM 9/13/2003]
Le Mans Master
Joined: Oct 2002
Posts: 7,098
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From: Las Vegas - Just stop perpetuating myths please.
Re: Carb Guru's...need help (79MakoL82)
:rolleyes: I’m just guessing here but if you’re positive the throttle cable is free and spring is OK, then sounds like that secondary air valve is opening on its own. The secondary butterflies have to be open for this so verify linkage. BTW there is a specification for how far the primary plate opens before the secondary plates start to open A simple test would be to fix that air valve shut somehow or remove the linkage to the secondary butterflies. Careful not to drop anything down into the intake. Only thing that controls the air-valve are counter-weights on the flapper. :)
Thread Starter
Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
Re: Carb Guru's...need help (cardo0)
Had the carb off. Everything seems to open when it's supposed to and nothing appears to be sticking. It's definately not the cable. Checked that several times. The only thing I can think of is that it's either a vaccum problem or something is happening with the electric choke that's not letting the primaries close all the way. Or maybe the fast idle cam is catching. I put the carb back on, and I'll have to check that tomorrow. I am by no means a card expert, and really don't have a clue as to what is happening here.
:confused:
:confused:
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Drifting
Joined: May 2002
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From: Back in Nebraska
Re: Carb Guru's...need help (79MakoL82)
This might sound funny and over simplified, But! I had a throttle sticking problem also, I tried everything on the carb and cables. Throttle would stick, then I would stomp on the pedal and it would release. I found that that the bottom of the pedal was catching on the edge of the plastic portion of the carpet. I know it sounds goofy, but check it out!
Thread Starter
Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
Re: Carb Guru's...need help (Apocolips)
Thanks for the reply's
Apocolips: I wish it was but the problem is definately at the carb. From the carb I can pop the accelerator arm and it'll kick down.
When I had the carb off, it did appear that the adjustment screw for the fast idle cam got caught every once in awhile. The only thing is, if the electric choke is operating properly, wouldn't the choke be open moving the cam out of the way? Also, even after the car is warmed up, I still have the problem and it revs way up past where a fast idle would be. In addition, Edelbrock dicounted the whole choke/fast idle cam theory as not the culprit. They think something is sticking. I just can't figure out what or how.
I'll keep playing with it.
Thanks again.
If anyone has any other ideas, I'll certainly check them out.
Apocolips: I wish it was but the problem is definately at the carb. From the carb I can pop the accelerator arm and it'll kick down.
When I had the carb off, it did appear that the adjustment screw for the fast idle cam got caught every once in awhile. The only thing is, if the electric choke is operating properly, wouldn't the choke be open moving the cam out of the way? Also, even after the car is warmed up, I still have the problem and it revs way up past where a fast idle would be. In addition, Edelbrock dicounted the whole choke/fast idle cam theory as not the culprit. They think something is sticking. I just can't figure out what or how.
I'll keep playing with it.
Thanks again.
If anyone has any other ideas, I'll certainly check them out.
Thread Starter
Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
Re: Carb Guru's...need help (79MakoL82)
OK. Here are my additional observations this morning.
I put the carb back on and started it up.
The electric choke seemed to work fine and as soon as it was warmed up, the fast idle cam swung out of the way. So it's not that.
What was strange was that while it was running, I slowly increased the rpm's by pushing the throttle arm by hand. When I let go, it stuck partially open mainting the higher rpm's (the fast idle cam was out of the way and not an issue). I could push the throttle arm back and it would reduce rpm's or if I popped it, it would snap back also. When I turned the car off and moved the throttle lever, it didn't seem to stick at all. It would return all the way to a fully closed position. It's not a secondary problem, because the accelerator arm was not pushed far enough to activate them and the rpm's weren't up that high.
So, I'm thinking it's a vaccum/accelerator cable sping issue. The accelerator cable springs are relatively new. Do they make different tension strengths for the accelerator cable? Maybe I just need a stronger spring.
Does any of this make sense?
I put the carb back on and started it up.
The electric choke seemed to work fine and as soon as it was warmed up, the fast idle cam swung out of the way. So it's not that.
What was strange was that while it was running, I slowly increased the rpm's by pushing the throttle arm by hand. When I let go, it stuck partially open mainting the higher rpm's (the fast idle cam was out of the way and not an issue). I could push the throttle arm back and it would reduce rpm's or if I popped it, it would snap back also. When I turned the car off and moved the throttle lever, it didn't seem to stick at all. It would return all the way to a fully closed position. It's not a secondary problem, because the accelerator arm was not pushed far enough to activate them and the rpm's weren't up that high.
So, I'm thinking it's a vaccum/accelerator cable sping issue. The accelerator cable springs are relatively new. Do they make different tension strengths for the accelerator cable? Maybe I just need a stronger spring.
Does any of this make sense?
Thread Starter
Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
Re: Carb Guru's...need help (79MakoL82)
OK. Here is a lesson in NEVER ASSUME.
Because of the observations this morning, I went out and bought a new return spring and installed it. Problem fixed.
I assumed that because the springs were relatively new, they were OK. The ones I bought looked a little stronger and as mentioned above, problem fixed.
Talk about making a mountain out of a mole hill. :bb
:crazy: :smash:
Thanks for the input. :cheers:
Because of the observations this morning, I went out and bought a new return spring and installed it. Problem fixed.
I assumed that because the springs were relatively new, they were OK. The ones I bought looked a little stronger and as mentioned above, problem fixed.
Talk about making a mountain out of a mole hill. :bb
:crazy: :smash:
Thanks for the input. :cheers:
Le Mans Master
Joined: Feb 1999
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From: Hoosier
Cruise-In III Veteran
Re: Carb Guru's...need help (79MakoL82)
Ok, but let me throw some caution your way. The stronger spring now overcomes something that's still wrong. Do another check....is there anything in the linkage that even hints at being out of parallel? Any long or short arm that might be catching just a bit?
Thread Starter
Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
Re: Carb Guru's...need help (biltogo)
Point taken.
But, it only had problems when the car was running. When it wasn't running and there was no vaccum, the flappers closed right up. Could it have been that the vaccum was holding the flappers open a little? The spring that I installed was a standard double return spring from the HELP! section of the auto parts store. When the carb was off the engine, everything seemed to open and close smoothly. That's what was causing me confusion. Everything seemed to operate fine when the car was off. After I replaced the spring, everything seems to work just fine.
I guess time will tell.
But, it only had problems when the car was running. When it wasn't running and there was no vaccum, the flappers closed right up. Could it have been that the vaccum was holding the flappers open a little? The spring that I installed was a standard double return spring from the HELP! section of the auto parts store. When the carb was off the engine, everything seemed to open and close smoothly. That's what was causing me confusion. Everything seemed to operate fine when the car was off. After I replaced the spring, everything seems to work just fine.
I guess time will tell.
