Rebuilding my 3465SA Carter BBS using Daytona #421. Verified kit number correct.

Question: Do I need to reuse my original, larger 3/16 check ball to ensure proper carburetor operation? Seems weird their kit would not come with the same size check balls as I’m removing. It came with two identical 5/32 check balls, but I removed a 3/16 check ball from the carb. Didn’t pay attention to which passage it came from, but based on searching past posts here, it was the accelerator pump passage.

Please advise, thanks.

Both balls are in the accelerator pump circuit. Info on ball size is inconsistent. Carter shows same-size balls, but there is no carb-subtype specificity. Walker shows a 5/32" ball at the bottom of the pump plunger well near the front of the carburetor, and a 3/16" ball in the discharge well near the outboard (driver's side as installed), but there is no carb-subtype specificity there, either. There was a major redesign of the bottom of the pump plunger well for '64 (the '63 and prior carbs have the ball in that location retained with a little round stamped metal dingus) and the '64-up carbs have a conical contour sloping down to the hole covered by this ball. There were some redesigns to the discharge well over the years, too. So it might be that the answer is not one or the other, but depends on which specific BBS one is working on.

It's been awhile since I rebuilt a BBS, but the way I recall it they all used the same size ball in both locations.

The definitive answer would come from Jon Hardgrove at The Carburetor Shop, who also supplies the world's best carburetor kits.

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