car idles fine but idle speed drops really low in drive/reverse.

[Rainbrodash6]

so I put a holley 2bbl with an adapter on my 318 in my 74 duster. and it starts and runs well but when I put it in gear id drops really low in if the motor isn't warmed up it dies. or if it is it dies when I try to move unless I jab the throttle a few times to keep it running. im not the best with cars I can do more than some people but I am trying to learn so any help is appreciated.

 

[67Dart273]

How did you set idle mixture and where is the timing? I'm guessing "lean"

 

[Rainbrodash6]

How did you set idle mixture and where is the timing? I'm guessing "lean"

the idle mixture screws are as they came from holley. and I dont know how to check the timing, I can tell you that it has vacuum timing advance, I replaced the vac hose on that today to see if that would help, it didn't.

also the car does not have a tach so I cant tell exact rpm's.

 

[harrisonm]

Is the choke hooked up and working properly? If so, the fast idle cam will kick in when the engine is cold and force the cold engine to idle faster. If that is not happening, a cold motor will die if you don't pump it. If that is the only problem, It should work fine once it is warmed up. I would also ask if the new carb is bigger (more cfm) or smaller than the previous one.

 

[375inStroke]

Probably something was off, then everything else adjusted to compensate. You need to have a timing light. Probably the idle screw is turned up too high because the timing is too low. Perhaps a vacuum leak. Do the throttle blades look like they are open at idle? Just look down the carb with the engine off. Look up lean best idle on Google for adjusting the idle screws.

 

[70aarcuda]

[ame="https://www.youtube.com/watch?v=UPGLUsW5ZeE"]How To Adjust The Idle Mixture Screws On Holley Carburetors - YouTube[/ame]

 

[70aarcuda]

and you will never get it to idle correctly until you get the timing set correctly.....

and getting the initial timing set correctly........

 

[Rainbrodash6]

Is the choke hooked up and working properly? If so, the fast idle cam will kick in when the engine is cold and force the cold engine to idle faster. If that is not happening, a cold motor will die if you don't pump it. If that is the only problem, It should work fine once it is warmed up. I would also ask if the new carb is bigger (more cfm) or smaller than the previous one.

it is manual choke and the problem happens even when the choke in in the full open possition, and the problem persists even when warmed up, just not as badly. when warm it will barely idle in gear instead of die. and the new carb is a 500cfm holley and old carb was carter bbd unknown cfm.

 

[RustyRatRod]

Trying to work on an older car without essential tools like a timing light, vacuum gauge and a dwell/tach meter is like hiring a hooker when your pecker has been blowed off in the war.

I can understand and even appreciate that you may have limited knowledge and still want to get into the hobby. But why on God's green earth do you and others limit yourselves so badly with tools? You can get a timing light, vacuum gauge and a dwell tach meter CHEAP. Read the instructions. Learn how to use them. Get yourself a factory CHRYSLER service manual for your car. Not Haynes or chiltons or other junk. CHRYSLER.

Sounds like very simple adjustment issues, but you will never figure it out without the necessary tools to get the job done. Refer again to my above comparison.

 

[AJ/FormS]

X2^^^^

I think I woulda spent the Holley money on tools, first.

 

[Mopar Tim]

trying to work on an older car without essential tools like a timing light, vacuum gauge and a dwell/tach meter is like hiring a hooker when your pecker has been blowed off in the war.

I can understand and even appreciate that you may have limited knowledge and still want to get into the hobby. But why on god's green earth do you and others limit yourselves so badly with tools? You can get a timing light, vacuum gauge and a dwell tach meter cheap. Read the instructions. Learn how to use them. Get yourself a factory chrysler service manual for your car. Not haynes or chiltons or other junk. Chrysler.

Sounds like very simple adjustment issues, but you will never figure it out without the necessary tools to get the job done. Refer again to my above comparison.

x2 mt

 

[sledger46]

I agree you should get the correct tools. Here is something you can try while you wait. Sandwiched between the fuel bowl and the main body of the carb is the metering plate. There should be a adjuster on the drivers and passengers side of the metering block you can turn with a small screw driver.

Start the car up and warm it up to operating temp. Shut the car off. Grab a paper and pencil and write down the changes you make or you could get very lost trying to get back to where you started. I would first back out both of the "idle mixture" screw 1/2 turn. Now write down what you did. Start the car and see how it idles. Drop the car into drive with the brake on and see how it idles. If it is "better", but idle is still low. put the car back in park and shut it off. Repeat the procedure and back out the "idle mixture screws another 1/2 turn. Start the car again and see how it idles in Park and in gear.

I would not go more then one full turn (in or out) with out a tach and vacuum gauge to verify what you are seeing/feeling.

If backing out the screw 1/2 turn makes things worse, then turn the screws back where you found them. Then try tightening the screws 1/2 turn and then test idle in Park and Drive. Make sure you write down every twist of the screws. It is possible turning the screws won't make any difference. In this case put the screws back where you found them and look else where for the source of the problem.