Zenith 2 Carburetor

A-Man

Senior Member
Having experienced a carburetor problem on my 1930 Deluxe Coupe, I am inspecting and repairing the ZENITH 2 carburetor. I am following the MODEL A FORD MECHANICS HANDBOOK by Les Andrews to clean out the passages. I have dirlled out the brass plugs with a 1/8" drill bit, as stated. The MANUAL then states to "clean passages with a small drill bit (#25)". However, a #25 bit is LARGER than 1/8", so if used would make the drill out hole for the brass plug larger. What is the correct bit size to use?

Along that line, what is the procedure to install and seal the replacement brass plugs?

Also, what is recommended to spray paint the carburetor, so as to be resistant to gasoline?

Thanks.
 

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Suggest that you check out the Tech articles at www.ocmafc.org which has a good article on rebuilding the carburetor. Under "Tom Endy's Special Topics" there is a article on "Zeinith Passageways" which suggests a preferred method of cleaning them out with a bent paperclip. (this may be too late for you now).

In terms of paint, I have had great success with Tremclad/Rustoleum Black semi-gloss from Home Depot etc. I dilute it down 10% with thinner prior to using it as the thicker formulation tends to show brush strokes.
 
You might try modela.org. Very comprehensive and sound advice......and free. I prefer to drill out the brass plugs. I wouldn't be too keen on using any drill in the passage ways unless as a last resort. I usually soak in carb cleaner for several days. I use air and pipe cleaners and very small wire to clean the passage ways. To date I have never ruined a carb by drilling out the plugs and the new plugs have all sealed very nicely. As far as the paint goes I prefer Aerogloss hot fuel proof model airplane paint. Make sure to flow test your carb jets. Frankly that's half the battle. I like many figured just throw a rebuild kit and your good to go. I found out the hard way. :cool:
 
one good reason for NOT using a drill to clean out the idle passage is that when you drill all the way to the idle port you can damage it in a heartbeat, and it is nearly impossible to reverse this damage. Remember cast iron is soft.Tom Endy's writeup is excellent. He has a method for checking each circuit.
 
If you want some gas resistant paint contact Aervo Industries Inc., Garderville, Nevada, 1-800-227-0196. You have to buy a 6 pack, cost is $ 5.27 a spray can, plus shipping. Order Aervoe Toolmate #512 which is flat black; they also have the same in semi-gloss black but I don't have the number.

You can handle the sprayed part after 15 minutes and it cures in 24 hours. I even sprayed the interior of my rebuilt carburetors to keep down rust buildup. I found after the paint dries you can rub the carb. with a terri-cloth towel and it takes on a light sheen but not glossy.

Ron
 
You can use Appliance Epoxy Semi-Gloss Black. Epoxy is impervious to gas. Rust-Oleum make Appliance Epoxy Black but I don't know if it's too glossy. I used to buy Appliance Epoxy Semi-Gloss Black made by United Coatings but they sold that line to Sherman Williams.
 
Vince, how are you getting the little devils out?

Modern/resto sources of advice vary a lot in quality, but should all be subjected to a double load of skepticism before you follow them!! Does the advice make sense?? Does it seem reasonable? What can you find in your owner's manual, Service Bulletins, and parts book on the topic BEFORE you look at the modern info?
Look especially at info in the Ford sources and in Page's explaining how the whatever FUNCTIONS. Basic understanding of how an object works will help you spot idiot advice.
If you haven't even gone as far as blowing thirty bucks on commonly available basic manuals above, forget about getting anything right from modern sources or being able to spot bad advice. Also forget about knowing enough to sort the many different answers from us random strangers on the internet into correct, poor, and dangerous categories!

I have always wanted to snip up a bunch of copies of repro Service Bulletins and the other basic sources and xerox the information in logical groupings. Mining the sources in their original state is pretty unwieldy. Brent in Tennessee mentione that he had such a source, with organize info from bulletins, judging standards, and the better internet info all copied into a coherent manual for his shop...
 
PS...your original questions were raised because of common sense observation: The numbers recommended in a book seemed to make no sense. A little reading and thinking would probably turn up no reason to question your own observations and made you more secure in your already correct judgement on drill sizes.
In holes like these that do not actually meter (until they get clogged down to smaller than the jets they feed...), there is no reason to choose a specific drill size in advance...runs in something that fits (by hand, I mean!), watch the rust and dirt fall out, then see if the next drill in tthe box will go in! Once you start to see shiny starting to happen on the walls, there is no reason to force a drill bigger than the hole...move on to brushes and solvents. And trust your judgement when reinforced by a bit of reading in the real manuals...you questioned the book because of common sense.
 
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