Throttle Shaft Gas Leak

[garfunkle55]

Alright, I've been having issues with my holley/weber 32/36. Long story short it'll start, run and drive; but the idle will get stuck around 1500 to 2000 once I've given it gas. If i punch the gas again real quick it'll lower back down. I haven't been able to get the electric choke to work so I said f*ck it and took it off. What might cause a leaky throttle shaft? or is it something else I'm not noticing that might be obvious?

Once I get it to idle and just sit there it'll stumble a little bit, kind of up and down maybe 50-100 rpm. REALLY ANNOYING!

Any ideas?

Thanks for the help

[2oodoor]

got any pictures of what you have?
I assume you removed the rod to the choke too, the one that kicks up the idle thing on the side of the carb?

sounds like you have some adjustments, hopefully your shafts are not leaking that bad cuz if they are the carb will not run very well. Also be very carefull not to put a lot of pressure on that shaft or bend it.

[garfunkle55]

Do you mean the rod that hooks up to the throttle linkage so it raises the idle? Cause i took that off, everything choke is off minus the choke plates. I just haven't gotten to that yet. I noticed that when the car is off and you hit the throttle just cycle it once, it'll make a kind of whining or leaking sound. Like something is draining or moving somewhere. Does that sound familiar?

[2oodoor]

Do you mean the rod that hooks up to the throttle linkage so it raises the idle? Cause i took that off, everything choke is off minus the choke plates. I just haven't gotten to that yet. I noticed that when the car is off and you hit the throttle just cycle it once, it'll make a kind of whining or leaking sound. Like something is draining or moving somewhere. Does that sound familiar?

noises with the car OFF? you got me unless it is the brake booster vacuum.. if it is something you only hear under the hood and not in the car that would be the accelerator pump squriting a shot of gas in.

[2ndGenGuy]

If your throttle shaft is leaking, it's not just gas that's coming out, but it's also vacuum getting in. That's why your idle is erratic.

What I would do first, is make sure that the base of the carb can NOT leak. Make sure you've got good gaskets and that it's flat and tight. Just make sure it's not got any other place to leak before you determine that the throttle shafts are leaking. Because you might actually fix the source of the leak first. But I'd bet that you've got a vacuum leak somewhere.

It's a common problem with the Holley 5200s, and I'd bet that's why so many of the cars that they came on seem like junk. (Mustang II, Pinto, etc) I've got two with leaky throttle shafts that I couldn't get to work at all. You might be able to get the shafts re-bushed at a carb shop (like Carb Connection in Seattle, or Carbs Unlimited in Auburn) for around $60, I'd bet.

[2ndGenGuy]

noises with the car OFF? you got me unless it is the brake booster vacuum.. if it is something you only hear under the hood and not in the car that would be the accelerator pump squriting a shot of gas in.

I was gonna say... I think that's the accelerator pump.

[garfunkle55]

I'll go out and buy some carb cleaner to make sure that there aren't any other vacuum leaks. Right now I've got a massive leak from taking the choke assembly off. its at the back of the carb. Its just a little hole with a black rubber ring, its where the diaphragm for the choke plugs in to. Just wondering if anyone could suggest something to plug that with. I don't want to quiksteel it or anything. I was thinking something that I could take out if I ever decide to put the choke back on. Thanks again.

And yeah the noise is only from the primary bbl and its with the car off and its 100% from the primary. It only lasts for maybe 10 seconds.

[2oodoor]

when gas leaks out of the throttle shaft it usually means gas is going down there when the car is not running.(throttle closed) That could be from a float or needle issue, or power valve stuck.
You could have left the choke hardware on it even though it didnt work I would think. Just would have had to lean it all the way out, loosen the three screws on the black thing and turn it so it does not close the choke no matter how cold it is out.

[garfunkle55]

I noticed that the throttle would kind of stick open just a pinch, so I hooked up a spring to help it close better. That seems to have worked. I'm going to an autoparts store to see if they have a plug that might work. I'll take the rubber ring for reference. If that doesn't work then I'll put the choke back together and try doing that.

[2ndGenGuy]

Might lube up the throttle linkage with some WD-40. My linkage started kinda sticking at one point, and just getting it oiled up helped with that quite a bit. And yeah, the return spring is also vital just for that reason.