This is my first post on the forum here and I would love some help.
I recently started working on a '73.
The Carb was in need of a rebuild because it sat around for 4+ years. So I rebuilt the car and took it into a shop to fix some other issues with it.
The shop put in a new transmission(old one was cracked) and a new electronic distributor(old one was a marine version).
All in all I get the car back and they tell me that the accelerator pump is not working. I don't remember having this issue when the car was brought in but now it can't get off a stop well without having to rev it and floor it. The shop guy said that with Holley's you need to change parts over after he learned that I rebuilt it.
The car chugs if the gas is pressed slow and if pressed further it seems that it is going to stall. It only does this in gear too (idk if this makes an issue) but when the car is in park and you hit the gas there isn't that shudder.
The distributor has a vacuum advance that the old one didn't, could be an issue?
Sorry for the long post but any help is greatly appreciated.

 

It's pretty simple to check the operation of the accel. pump. Just take the air cleaner off and work the throttle. You should see fuel spray from the nozzles. Did you set the accel. pump linkage free play according to the instructions? I would check that first before looking at other issues.

 

If your car did not act this way when it was delivered to the 'repair' shop, one of two things has happened:
1) one of the mechanics has accidentally knocked a vacuum hose loose or changed the timing, etc. which has caused the car to perform poorly;
2) one of the mechanics has intentionally knocked a vacuum hose loose or changed the timing, etc. so that they can convince you that they need to do more work on the car.

Solution: Tell the manager at the repair shop that the car didn't act this way when you brought it to them and you won't accept the car running in that condition. If it is a reputable shop, they will take another look...free of charge to you...and try to find what they messed up. If they are NOT so reputable, they'll give you the 'run-around' or tell you to get lost.

If the latter event happens, report them to the Better Business Bureau and submit a formal complaint (via internet) to your State's Office of the Attorney General. Then check your car over for any 'loose' vacuum hoses (don't forget the vacuum modulator on the auto tranny) [if you have one]. Also check timing, removed or swapped spark plugs connectors, low tranny oil level and fill tank with fresh gas. If that doesn't solve your problem, try to find a more reputable place to take your car.

Oh. There is no "diaphragm" on your accelerator pump...just a seal on a piston that pushes a shot of straight gasoline into your carb's venturi when you depress the pedal. A bad accel pump seal will not hurt the car's running behavior...it will just 'stumble' when you go WOT.

 

Burners-
Opening the throttle with the car off gives a good 1-1.5sec spray of gas. And the 'free play' was fine according to the directions.

7T1vette-
I would assume that they did change the timing since they added a whole different distributor. Which is why I think that something is off with that.

I will take a look too make sure all the vacuum hoses are connected.
Is it alright to just pull off the vacuum advance from the distributor to the carb and plug it to see if that's causing the issue? (read somewhere that too much vac could cause the car to "chug")

 

So quick update, checked all the vacuum hoses and they are all connected.
Took off the Vacuum Advance to see if that was causing an issue and when driving it with the vacuum off the distributor the car seemed to "chug" later in the acceleration.
So I called the shop up that did the work and told them of my concerns about the timing. They said that they couldn't do the timing right because they didn't know what cam was in the car since it is not stock. So they just kinda set it where the car "seemed" to run best. He also admitted to me that they did not notice the "chug" until after they dropped in the new tranny and distributor.

 

go get a timing light at sears and check it yourself...I would guess it should be any where from 4-12 degrees initial. What size are the shooters in the top of your carb? If they are too small this could cause the stumble.

 

Thanks for the suggestion.

I do believe that I have a timing light. Unfortunately I do not know how to check it. Just started getting into the car and am not very mechanically savvy. As for the shooters, if you are talking of the one in the choke tower, it is the one that has no needles coming out of it. And I know that the car worked before with them on, so I just kind of assumed that it was not those.

 

Thanks for the help everyone. Car just got fixed so it doesn't have the "bog". The timing was set at 8 and had to be clocked back to 14.