Throttle issue

[Guitylerham]

Hello,
My throttle does not always want to return to zero! I've removed the linkage and the lever still sticks when I blip it and let it fall back to idle with my finger. I got a new spring for it but I don't know if it's really the same tension or not and the same problem happens so I put the old one back on. Some peopel have put a second spring pulling the same direction but opposite the original and other's have said that's tacky and should be fixed but I'm not sure what I should be looking at to fix!

 

[Pbum5]

Summit and other parts stores sell double springs.
That should cure your problem.

 

[Guitylerham]

I have a 289 with a 2bbl autolite 2100 btw. I might look into the double spring, but you wouldn't think a properly build carb woudl need one though.

 

[2nd Mustang]

I have a 289 with a 2bbl autolite 2100 btw. I might look into the double spring, but you wouldn't think a properly build carb woudl need one though.

I've always thought that a double spring was more of a safety issue, just incase the return spring broke, the second spring would not allow the throttle to stick open.

Anyway, being that the carb might be very old, try some carb cleaner at the base where the "whatyoumacallit" throttle rod goes through the carb with the butterflies. It may just be full of junk and sticking.

 

[Tim65GT]

I had the same problem. I bought a dual spring setup and built a bracket:

 

[Guitylerham]

Ok, so I realized I don't have a dashpot on my carb (although I thought I would have because it's a C4). Also, I noticed that the throttle only sticks when the engine is running, otherwise when it is off, the throttle always returns back to the correct spot. I've added a second spring to give a little more tension. See in the drawing below. Any ideas as to why this only happens when it's running?

 

[Guitylerham]

Here's the pic

 

[Tim65GT]

look on the other side of the carb to see if there is a choke mechanism on the shaft. most chokes also crack the throttle open a little. It could be out of adjustment or broken.

 

[mfp4073]

Also, check your local parts stores before ordering something fancy and expensive.