Carb Mixture Screws / Gas Leak



Feb 8, 2018
Houston, TX
Edelbrock 1405 Carburetor

So i rebuilt my carb for no apparent reason. Just because it was 10yrs old and very dirty. Thought rebuilding it would finish fine tuning my idle. So i used new gaskets, needles, and floaters. Everything else I re used.

My original floaters were nowhere near 7/16 - 15/16 heights so I removed them and set them aside. I adjusted the new floaters to the 7/16 - 15/16 height. Cleaned everything with degreaser and water then blew with a keyboard compressed air can (not sure if this is strong enough)

After assembly and installation, my idle mixture screws have no effect when adjusting them while the engine is on. There is also a hole on the passenger side of the carb under where the electric choke goes. This hole sucks air while engine is on and leaks gas while engine is off.

So after all this, the carb does an awkward sound from time to time (maybe every 5-10 seconds) and i can't get the mixture screws to adjust. Also the driver side jet seems to be dumping little to no gas. Does the floaters have anything to do with it? Is the vacuum sucking hole normal?

Thanks fellas.



Feb 8, 2018
Houston, TX
Ok so i determined that the hole is supposed to be plugged with a screw by googling some 1405 photos.

Now i was planning on removing the top and swapping out the floaters to my old original ones until i pulled the rod tabs and seen one of them was stuck. Not sure how it got stuck eat past the surface level. I unstuck it and the hole is not leaking gas after i shut the engine off anymore, so maybe that was causing it to flood and leak?

However, the mixture screws still have no affect while adjusting them. If i pull them completely out, the engine will idle high then die out after about 10 seconds.

If anybody can shine the light on what's going on, it would be greatly appreciated. Thanks.
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