Sticking throttle

[Ed H.]

So, after ~ 35 years, we're road worthy! But we have a minor sticky throttle problem. (Brake pedal too, but that is not as exciting, it just leaves the brake lights on...).

It's not an 'absolute' stick, so, for instance, when shifting with one's foot in it a little, it seems 'OK', but if just puttering along, one discovers that a foot off the gas pedal has no effect. One can pull the pedal up, OK, or blip it, mostly returns to normal idle.

So, suggestions? Historically I've not had shielding, putting a bit of a dog leg in the cable.


So we worked on it a bit, had it hanging up and wiggled the bowden cable hither, thither and yon, to no positive effect. We connected the spring to a different 'hole' stretching the spring more, and that cured the problem, but the cure (difficulty modulating the gas, LOL) was worse than the problem. I can see another way, which won't stretch the spring so much, but at the moment I've other things I must do.

[Ed H.]

Re: Sticking throttle


So I'm now convinced that the problem is on the interior side of the firewall. The slightest little sideways tap on the pedal and the revs drop right down to idle. It's also getting better, so probably just have to work the 30+ years of sitting kinks out of it.

[Chris H.]

[Ed H.]

Re: Sticking throttle

Hi Chris - thank you. In this case it's all new stuff forward of the firewall, and it does seem to be improving with exercise. Stuff still to do, like figure out why the speedo is incommunicado...

[Richard G.]

Re: Sticking throttle

Disconnect the carburetor end of the throttle cable and hold onto it, use a pliers if needed.
Then have someone work the throttle from inside the car while you feel the cable for smoothness.
Pay especially close attention to how much force you have to use, to return the cable to idle position, when the driver lets off the gas.
If the issue is in the cable my bet is you will be able to feel it.
Rick

[Mark E.]

Re: Sticking throttle

Is the cable routed properly? The bends as it goes under the ignition shielding then over the top of the valve cover may be contributing to the problem.

I don't have a small block C3 for reference, but I don't recall the cable sitting on top of the valve cover.

[Bill L.]

Re: Sticking throttle

Ed,

Looks to me like the accelerator cable is not routed correctly. It should not be over the valve cover. Did they run the cable through the correct hole in the firewall? Did they use the correct throttle cable bracket on the holly carb?

Bill

[Ed H.]

Re: Sticking throttle

OK, problem resolved. My previous conclusion that the problem had to be on 'my' side of the firewall proved correct. Where the linkage from the pedal to the cable makes the dog leg thru the pillow-block like piece, I squirted a bit of slippery stuff on either side of it and, voila! Problem 98% resolved.

I don't see how the routing could be done differently, but we think that the cable should make a 'gentler' curve as it rounds the shielding and heads towards the cable bracket. That would also keep it clear of the rocker cover. I may try using a wire tie to the shielding bracket to see if that will 'train' the cable. In any case, it's no longer quite as negatively exciting to drive! Thank you all for your help.

[Ed H.]

Re: Sticking throttle



That's the culprit should there be any doubt.