Quote:
Originally Posted by '72customdeluxe
Do you mean the oil smells like gas after you shut it off? That's pretty normal with a carb, especially with a q-jet. They leak fuel down into the cylinders after shut off. If there's ALOT of fuel in the oil that means it's likely too rich. Nothing to do with the type of carb
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If your carb is draining gas into the intake after you shut it off, you have a carburetor problem, and need to get it fixed. They shouldn't leak at all.
With cruise mixture, I like to lean it out until it surges at highway speeds, and then make it a reasonable amount richer than that.
For accelerating, it's pretty safe to say that if it feels sluggish, it's probably rich. If you get a complete "falls on it's face" dead-spot, and then it picks up, it's probably lean.
For idle mixture, start at a set amount of turns out on each screw (2 turns?) then, open one screw a 1/4 turn, then the other 1/4 turn... Did the idle increase? If it increased, go another 1/4 turn on each screw... is it still increasing? You will have to keep turning the idle speed down if the idle keeps increasing with the turns on your mixture screws. When you get to the point that opening the screws any further doesn't increase idle speed, it's pretty close; at this point you could probably turn each screw in a small amount just to lean out the idle a tad.
If you have a vacuum gauge, you can use the above procedure, but set the idle screws to maintain a maximum vacuum reading (you'll still want to keep dialing back the idle speed when changing the mixture screws).
In my hunt for a near perfect tune, I picked up a wideband O2 controller. I went wit a JAW DIY system. I have less than $150 in it, and so far, it seems to be worth every penny. It takes all the guessing out of the equation.