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adjusting Autolight 4100 4 barrel carb advice

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Can someone tell me how to tune my Autolight 4 barrel carb.  It's the original on my 289 "A"

Seems that it is running too rich as I am getting black powder on my exhaust tips and the "spitting" out of the tailpipes.
Also it is getting to where the engine wants to die at atop sighns.
Thanks in advance!


Go to the FAQ section of this portion of the forum. Glen (Soaring) has several links that should help.

I would first check the timing to make sure the black smoke is not a timing issue before I blamed it on the 4100.  If you still think it's the 4100, then try adjusting your front idle adjustment screws on the bottom of the carb.  Turn then both all the way in, then out about 1 3/4 turns and keep turning out on both of them 1/4 turn with the engine running at a time until you get maximum idling performance.  If you still get black smoke after setting the timing and adjusting the idle screws, then you may have worn rings.  Just make sure it is black and not dark blue smoke.  Dark blue would indicate burning oil. 

Golly gee Batman (oops, I mean Bat person - politically correct you know), I thought the screw on the right side of the base was for the right side venturi and the screw on the left side of the base was for the left side venturi. At least that's the way it is on my three 4100 carburetor equipped cars, and, son of a gun, the same applies to my 3100 Holley Bugspray two barrel carburetor on my VW.

It depends on what you call left and right.  MOST folks call the right side of a carburetor by looking at it from the front of the engine, not from the driver's seat. 


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