The Ford Barn

mleder · 10-16-2025, 10:28 PM

At the ever popular clinic of the Twin Cities Model A Ford Cub tonight, an oddity was presented. A member bought a "Rebuilt" carburetor off of the internet. It always ran rich and gas mileage was poor. The member opened it up and removed the GAV adjusting needle assembly. He had a new one on the bench and it measured 3/8' longer from the tip to the beginning of the threads that go into the cast iron. That was the problem of the rich running and poor mileage . That needle never really seated or closed enough. The question is what do you think this GAV needle was supposed to fit. A Model B Zenith?. I 've heard there is version of the Model A Zenith that has a removable seat for the GAV , does that take a shorter needle?. Can someone help with an explanation?.

10-16-2025, 10:28 PM	#1
mleder Senior Member Join Date: May 2010 Posts: 205	Zenith Carburetor oddity At the ever popular clinic of the Twin Cities Model A Ford Cub tonight, an oddity was presented. A member bought a "Rebuilt" carburetor off of the internet. It always ran rich and gas mileage was poor. The member opened it up and removed the GAV adjusting needle assembly. He had a new one on the bench and it measured 3/8' longer from the tip to the beginning of the threads that go into the cast iron. That was the problem of the rich running and poor mileage . That needle never really seated or closed enough. The question is what do you think this GAV needle was supposed to fit. A Model B Zenith?. I 've heard there is version of the Model A Zenith that has a removable seat for the GAV , does that take a shorter needle?. Can someone help with an explanation?.