I got gas to the carb however notice a pretty good leak. It looks like I may need a new gasket. I was hoping to at least try and tighten the bottom half up to the top half. I was playing with a spare carb I have and couldn't figure out how to separate or tighten the bottom and top.
looks like the same carb I have on my 29 bolt on bottom of bowl //1/2/or 9/16 take out and slowly separate at seam all the way around evenly can replace all gaskets for 3--4 dollars from snyders or langs body gasket usually needs fit
You might find this site useful - be patient, the .pdf file is fairly large.
Float valve is sticking, has crud in it or needs to have shims added under it. You do not bend the arm like the T's. You add shims between the float and housing to drop the level down. Do you also have gas dripping out the intake/rear?
When you reassemble the carb, do not over tighten the 9/16 bolt that holds the two halves together. Have seen countless cracked Zenith's over the years where someone got zealous with the wrench.
I was also having gas leaking problems with a Zenith Carb. on our 29 model A. I replaced the ball check valve and float. There should be 1" measured from the float seam (Where upper and bottom half Join) to the upper carb. housing surface (Where gasket seals). The float height seems to be a major concern. You can adjust the float height by changing the gasket thickness under the float check valve.
Now I have a question.....I replaced the Zenith -1 carb with a Zenith -2. What is the difference between the -1 & -2 carb? Which is correct for a 29 model A?
Les, the only difference is the manufacturer. All parts are interchangeable. I don't have the book handy to say for certain which carb was made by which but the three manufactures were Zenith, Holley and Ford. Ether carb would be correct but there are some other differences like the actual lettering on the carb that places it within the time frame of your car.
Both carbs were marked Zenith......one was marked "Zenith -1 and the other Zenith -2". It was not obvious to me when looking inside each what the differences were. Possibly jet sizes?
I'm using a Tillitson ? model A replacement carb on our model T with a no name manifold and really like how well that set up works. Gets 21 mpg and performs much better compared to an NH. It idles well and does not load up. I also tried a Zenith and model B and they would load up.
the biggest problem (I've found) with the Model A type Zenith carburetor are the reproduction jets. They are made in two pieces, and oftentimes leak at the joint. Take out the two that come up through the bottom of the carb; one unscrews from the bottom, the other takes a 5/16' long socket or a hollow socket driver. Clean them thoroughly, and then solder the seam you will see there--doesn't have to be pretty, just well-soldered. On the one that comes out the bottom you do have to be careful of the threads nearby and the solder joint can't be too big. This solves a lot of the leaking problems. It might not be a bad idea to also solder the seam on the compensating jet that screws into the top casting also. I'm working from memory here guys!
I forget what the diff is between Zenith 1 & 2, might just be the adjustable mixture needle seat, one is a brass piece threaded in, one is just the casting machined.
Float level is somewhat critical on these, too high and it leaks, a little too high and it floods on a quick stop. Too low and no power!
Even rebuilt they sometimes stick. Turn off gas, rap top of carb with a hammer handle, turn gas back on--FIXED!
When first installing a dry carb, remember that the flow of gas into an empty bowl can override the float, so turn on gas, count to ten, turn gas off, wait about 30 seconds, turn gas back on.
I think they're a pretty reliable carb, and easy to fix on the road too.
BTW, story is the first prototype had 14 scres to hold it together, Henry Ford said "too many!" and the designer got down to three screws, Henry said, "Well, 14 to 3, how about 1?" )or something like that), and so it is, one bolt holds it together!