Tuning carb with two screws

My 3.0L has a Holley 2 bbl mar

My 3.0L has a Holley 2 bbl marine carb on it. There are two screws that adjust the mixture and also the idle adjustment screw. I read somewhere that each of the two screws are for each barrel and they have to be adjusted the same amount. Is this true? Anyone have experience tuning carbs like this?

The thing is brand new for the most part and dies when given gas in gear. The engine revs fine in neutral.

"NOT TRUE AT ALL. ONE SCREW IS

"NOT TRUE AT ALL. ONE SCREW IS AIR OTHER IS FUEL. I WAS TOLS THE SAME THING. Start the boat, if there are no hesitations at all in neutral when you rev it up (or backfires) there should be no issue with these screws. However, if you want to try it anyways, with the engine at an idle, turn both screws in one at a time until the engine starts to run rough, then turn them out until the engine begines to run rough. find the half way point between the two rough sides. this will set the carb pretty well."

"Russ, Generally each barrel w

"Russ, Generally each barrel will have a mixture screw for idle adjustment. They are usually fuel screws, so tightening them makes a lean mixture. The third screw is a idle speed (or stop) screw. It sets the minimum idle speed, and is located near the throttle linkage. To adjust the idle mixture, usually you will set it to it's initial setting, and turn it in or out until the motor runs smooth. Hi performance motors are tuned with a vacuum gauge on each carb or barrel to assure they are synchronized. it is not necessary for your application.

If you motor dies when you try to accelerate, check the accelerator pumps in the carbs. When you advance the throttle you should see and hear gas squirting into the motor. If you don't hear or see it, you need to fix it."

Fixed the probem. It actually

Fixed the probem. It actually wasn't the carb. It was the interupter switch and old shifter cables. The switch was good but due to friction in the cables it was pushing the switch at the wrong time. Fixed it with a nrigged push button switch on the dash. Push right before I go into and outta gears. Worx like a charge and doesn't require me to shell out cash for new cables.

The problem was hard to explain and could not be fixed with shifter adjustments.