Just rebuilt carb, throttle sticky when bottom screws tightned

[mkelley88]

Hi everyone, I have just rebuilt my Rochester Dual-Jet 210, and I don't understand why the throttle is sticking when the bottom screws are tightned even the slightest bit. The car runs alot better now, but I pulled the carb again to check for the 'stickiness'. As long as the bottom screws are not tightned, the throttle moves freely (even with the throttle pump attached).

Any Ideas?

-Matt

[maxwedge]

Welcome to AF, sounds like the lower throttle plate body is warped, see if you can see where the interference is in the plate bores, there is no way from here to determine where the bind is ,the alignmnet of the throttle plates is critical of course.

[mkelley88]

It's fixed! I was pulling it on and off trying to figure out the problem, and I somehow got it on right. However, I didn't pull it back off to figure it what was wrong. I was just happy my problem was resolved.

I have another question.
(I have a 260 V8, Dual-jet 210)

My idle speed is a little high, and I cannot set the idle any lower than it is. Maybe the carb isn't tuned properly? Idle is supposed to be 800 RPM in park, I think it is maybe 100 - 200 RPMs higher than it should be. I have tried adjusting the mixture, but could not tell if it was lean or rich. Vaccum gauge didn't help a whole lot ether. And my garage and car both lack an RPM gauge.

[maxwedge]

Is there an throttle stop device on the carb or manifold that acts as an anti-diesel solenoid, this can affect base idle if not operating properly, check the throttle linkage make sure the idle stop is all the way down and the plates are shut, aside from a vacuum leak this is the only source of not obtaining the proper low end of the idle adjustment. Also what car is this on?

[mkelley88]

'78 Olds Cutlass Supreme

Has non-working A/C so i have disabled the solonoid for increasing idle speed when A/C kicks on.

I replaced most of the vacuum hoses, and i'm getting around 18 on my vacuum gauge at idle. It drops to 14 or so when I shift to drive. I think because of the higher rpm it is causing a load on the engine when I am not moving. During acceleration it is hard to keep the vacuum above 3-5. (probably normal?) But I am pushing a little harder on the brake now to stop than I was before.