Secondaries stuck?

[Daves74chally]

Bolted up the carb I just bought today, its used and not going well. Ran it for a bit seemed fine, throttle seemed a lil sticky so I threw A return spring on it, thought that did the trick. Did it again so I was playing around with the linkage for the secondaries and the idle went back to normal.  End of the day I back it out of the shop and parked it. Gave her a lil rev and it stuck at 2k.... so I quickly shut it off and it began to diesel badly!  Did that for about 10-15 seconds. Didnt know how to get it to stop but it stopped eventually. 

I think it has something to do with the secondaries, maybe they are not closing all the way.

Where do you guys think I should start on this?

[Super Blue 72]

I'm no carb expert but the fact that you mentioned the throttle seemed a little sticky and you threw on a return speing makes me wonder if the carb butterflies (primaries) are hanging up on something, like either the gasket or if the shaft for the butterflies are gummed up and hanging up. 

When the carb was off the engine how was the throttle action?  Smooth or sticky?

What kind of carb is this?  Vacuum or mechanical secondaries?  Why do you think the secondaries are stuck and not the primaries?

Also check for vacuum leaks!

[Daves74chally]

Its vacuums secondaries. The butterfly's operated like new, I dont think there is a vacuum leak, not for sure though.
I say its the secondaries because like I said before when I was playing around with the linkage to the secondaries and thats when it returned to complete idle. So I figured that something was keeping them from fully closing. 

This is a 670 Holley street avenger btw

I didnt get too much time today to investigate, tmw I should have some time to inspect this further.

[Moparal]

Maybe because im old school. But when I used to bolt any 4v carb down on an intake, I held all the butterflies open when I first snugged all 4 corners down. This helped to center the carb better and keep the gasket from catching the throttle blades.

[Daves74chally]

I understand what your saying.
I dont think thats the case, this is the type of gasket I am using.  http://www.mdparts.com/pictures/carburetor-mounting-gasketfp600681.jpg

I also have carb studs that seem to keep the carb centered on the intake.

[Super Blue 72]

Just for the fun of it, move the throttle to gt a feel for it then loosen the 4 nuts holding down the carb so the cab has some movement then try the throttle agin to see if theres a difference in the feel of the throttle.  Worth a try.  Take off any return springs before you try this.

[73EStroker]

Also - I always turn my engines off in gear (manual) and be ready to let the clutch out to prevent this. In auto I always shut the key off in drive so that dieseling is not too much of a problem. Dem gaz injuns are not built to preignite like de diesel does constantly.

[71chally416]

Most Holleys (and about every DP) require a strong return spring (or even two) that also makes the pedal feel heavy compared to a stocker. If you're trying to use a stock return spring from a Carter carb that could be your problem. You might also have a warped base plate that's binding the butterflys. They're real easy to warp or even break on the Holleys. Might wanna take it off and make sure it's flat with a straight edge and that it operates freely unbolted.  Also make sure your linkage isn't hanging up on something on the Intake.