Zenith drips

Jerry, if I recall correctly, the float should be at 5/8". If debris enters the carb, all bets are off regarding any recent rebuild. I used Steve Pargetters Zenith restoration book.


Your fuel valve may be leaking under the tank or on the firewall for late 31's.
 
Clean out the needle valve and then change the float level to 5/8"

Then check your shutoff to see why that is allowing fuel into the carb.
 
Any thoughts on an inline filter. I have one in the shut off. I leave the shut off in the on position, unless car sits for a while.
 
These slides may help you:
 

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Boy! It's hotter than a two dollar pistol here. I set my wrenches on the step plate and couldn't touch them after a minute. Anyway I'm glad this subject came up because my Zenith has had a problem the last couple months. My engine would only run with the idle mixture adjustment screw closed and the GAV open three turns. Also back-firing when engine braking down hill. I had the carb apart before, but nothing was plugged. I pulled it apart yesterday and the same, nothing was plugged, soaked all the brass parts overnight and reassembled today. I did find two things that I corrected... One of the jets in the venturi was lower than the other so I shimmed it to be at the correct height in Bob's slide show he posted. The other thing was the float was a little high. Shimmed the ball valve with a thicker washer so the float shuts off the valve at 5/8". Reinstalled the carb, Lo and Behold it purred like a kitten. GAV shut and idle mixture screw at 1 3/4 turns open. I was able to get the idle down to 400 RPM without stalling, but ended up leaving it at 550 RPM. Thanks to Bob Bidonde for the slides, and Tom Endy for the write-up on Zenith Carburetor Documentation. Both were instrumental. I'm going to have a tall glass of iced tea and stay inside for the remainder of the day.
 
Was just helping a guy with a dripping Zenith. When I removed the drain plug, the main jet fell out! Re installed, tightly, . Carb no longer drips!
 
Bob Bidonde, thanks for the info about the 1/8" vent hole, I dropped the bowl assembly off my A yesterday and found no vent hole, so I did the mod as listed. Haven't ran the engine yet. Just wonderin' if you know what differences if any I might experience.
Respectfully, Ken
 
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