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Old 03-13-2026, 08:30 PM   #21
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Default Re: Ditched the "Air Maze"...

Me too
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Old 03-14-2026, 10:03 AM   #22
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Default Re: Ditched the "Air Maze"...

you guys should paint a car without a paint mask and see what happens. same as an engine breathing without a filter.

lets stir it up a bit
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Old 03-14-2026, 10:10 AM   #23
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Default Re: Ditched the "Air Maze"...

Adding an oil filter to the engine can do a lot of what an air filter would do.
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Old 03-14-2026, 10:20 AM   #24
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Default Re: Ditched the "Air Maze"...

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Adding an oil filter to the engine can do a lot of what an air filter would do.
but Ford never used one of those either
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Old 03-14-2026, 10:22 AM   #25
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Default Re: Ditched the "Air Maze"...

IGNORANCE IS BLISS......

Happy days to all who celebrate it.
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Old 03-14-2026, 11:03 AM   #26
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Default Re: Ditched the "Air Maze"...

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Thankfully, we can all make that decision for ourselves.

I figure there's no real filtration with the Air Maze. I have the engine pans mounted and the levels of dust here are minimal. What? Me worry?

I need to pull the passenger side pan, strip it and repaint (like that when I got her). That Tillotson leaks and the paint is falling off on the inside. Took me about a minute to learn I should close the fuel valve and run the bowl dry every time I shut her down.

My problem is that I get out after turning the fuel valve off...and keep forgetting to go back and turn the key off!
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Old 03-14-2026, 11:06 AM   #27
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Default Re: Ditched the "Air Maze"...

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but Ford never used one of those either
The argument against the air filter isn't purely originality, it's that putting a constriction on the carb intake changes the effective atmospheric pressure inside the carb and alters its function. Other elements of the engine bay design, such as the rearward-facing intake, help compensate for the lack of a filter.

The way Ford compensated for the lack of an oil filter was to use non-detergent oil, change the oil every 500 miles, and include sludge removal on the maintenance list. Airborne contaminants would become entrained in the oil and gradually sink to the bottom of the sump.

But if you're using detergent oil, which most people are, you're already pushing that system away from how it was designed, because the detergents will hold contaminants in suspension, sending them through the engine over and over. The use of an oil filter returns this system to balance and improves its efficacy over the original design.
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Old 03-14-2026, 11:19 AM   #28
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Default Re: Ditched the "Air Maze"...

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The argument against the air filter isn't purely originality, it's that putting a constriction on the carb intake changes the effective atmospheric pressure inside the carb and alters its function. Other elements of the engine bay design, such as the rearward-facing intake, help compensate for the lack of a filter.

The way Ford compensated for the lack of an oil filter was to use non-detergent oil, change the oil every 500 miles, and include sludge removal on the maintenance list. Airborne contaminants would become entrained in the oil and gradually sink to the bottom of the sump.

But if you're using detergent oil, which most people are, you're already pushing that system away from how it was designed, because the detergents will hold contaminants in suspension, sending them through the engine over and over. The use of an oil filter returns this system to balance and improves its efficacy over the original design.
i think we all know that stuff.
i would argue that air cleaners and oil filters were being added to manufactured vehicles and equipment at the same time frame as the model A was being built. manufactures knew that contaminants in the air as well as the oil would harm the engine so they started making filters as part of the vehicle's standard components.. and there were no detergent oils when all this started.
Ford was thrifty and stubborn i imagine he saved millions of dollars not putting air cleaners on.
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Old 03-14-2026, 11:24 AM   #29
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Default Re: Ditched the "Air Maze"...

Running without an air filter and oil filter is really good for the engine. That is why all modern cars do not have either one. Ha ha.
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Old 03-14-2026, 05:50 PM   #30
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Default Re: Ditched the "Air Maze"...

I have many farm tractors that have a gravity fed fuel system, and they all have air cleaners on them, and yes they do leak sometimes. But the air cleaners are higher than the carb, with a pipe and flexible hose connecting them, so they don't fill with gasoline.


They almost all have Marvel Schebler carburetors on them, I have not looked closely at the Marvels to see if they have the pressure balanced system on them, or they may not work the same as the Model A carb.


Is the Marvel Schebler carb for the Model A pressure balanced?


I would be interested in the pressure balancing to run an air filter. While everyone may so and think that there's minimal dirt, I spent a lot of money on my engine, and I put a lot of miles on it, so I would like it to last.
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Old 03-14-2026, 06:14 PM   #31
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Default Re: Ditched the "Air Maze"...

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I have many farm tractors that have a gravity fed fuel system, and they all have air cleaners on them, and yes they do leak sometimes. But the air cleaners are higher than the carb, with a pipe and flexible hose connecting them, so they don't fill with gasoline.


They almost all have Marvel Schebler carburetors on them, I have not looked closely at the Marvels to see if they have the pressure balanced system on them, or they may not work the same as the Model A carb.


Is the Marvel Schebler carb for the Model A pressure balanced?


I would be interested in the pressure balancing to run an air filter. While everyone may so and think that there's minimal dirt, I spent a lot of money on my engine, and I put a lot of miles on it, so I would like it to last.
i work on a 15-30 mccormack deering which uses its own brand (stock) of carb. it has an air cleaner and for sure it has an air balance tube from the intake pipe to the carb. it is original.
i also work on a 20-35 allis chalmers with an air cleaner, and a carb that looks like a marvel (im guessing the carb is not original), i don't see a separate tube on it.
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Old 03-15-2026, 09:23 AM   #32
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Default Re: Ditched the "Air Maze"...

Because it was my former profession, I'd like to share some data regarding air and oil filtration. This isn't meant to lead to further discussion or persuasion, but simply to provide typical —and reliable— figures that everyone can draw their own conclusions from.


The A engine requires, on average, appximately 15 liters of gasoline for every 100 km driven. For each liter of gasoline, around 1:>14 parts by weight of air are needed for combustion, resulting in 180 m³ of intake air per 100 km.
Converted to the average dust from paved roads, the amount of dirt drawn in is 1 gram per 1000 km. That's more than 1 spoon.
This road dust consists largely of glass-hard silicon and quartz. This is the first component to wear down the honing marks in the cylinder.


Approximately 1/4 of this dust also ends up in the engine oil. This furthers abrasion of the soft bearing shells, causing them to wear out more than necessary.


Even a simple (mainstream) oil filter cannot completely remove this dust, because the smallest micrometers can pass through the filter pores. However, it still removes more than 80%.


When Ford engines were designed at the beginning of the last century, I think this effect of dust and how much it increases wear was probably not yet known.


The argument that the dust settles in the sludge at the bottom of the oil pan when using HD-oil (= without depersants, etc.) is misleading. While some of it is bound, as soon as the engine is running and the oil is hot, a large portion of the sludge is stirred up again and enters the entire lubrication system.
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Old 03-15-2026, 09:25 AM   #33
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Default Re: Ditched the "Air Maze"...

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I pulled the maze off mine for the same reason. Never could get it to run or idle properly.

Same experience here with an Air-Maze 'filter' on the '29 Tudor It came on the car as we bought it.
It fell off on the highway one day as the set screw holding it on a Tillotson carb couldn't 'hold it on' as the air inlet opening had a slight bend from the screw.
Vibrations made it fall off.


That car never ran so good after that happened. That was in about 1975, and I've never run one since!!
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Old 03-15-2026, 11:24 AM   #34
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Default Re: Ditched the "Air Maze"...

NO ONE IN THEIR RIGHT MIND WOULD BE AGAINST USING AN AIR FILTER, THAT WOULD BE RIDICULOUS.

That's not ever the intent when talking about Model A's and air cleaners.

The intent is to be educated that there are two distinctly different designs of carburetor, one type that the model A uses that has potential risk of engine damage, and the other one that does not, plain and simple facts.
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Old 03-15-2026, 01:10 PM   #35
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Default Re: Ditched the "Air Maze"...

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NO ONE IN THEIR RIGHT MIND WOULD BE AGAINST USING AN AIR FILTER, THAT WOULD BE RIDICULOUS.

That's not ever the intent when talking about Model A's and air cleaners.

The intent is to be educated that there are two distinctly different designs of carburetor, one type that the model A uses that has potential risk of engine damage, and the other one that does not, plain and simple facts.
i am curious about the the two different designs of Model A carburetors.
please list them and their potential issues.

in the 60 years that i have been working on and driving Model A's i have never personally witnessed a model A carburetor damaging a model A engine. just lucky i quess.
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Old 03-15-2026, 01:58 PM   #36
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Default Re: Ditched the "Air Maze"...

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(...) The intent is to be educated that there are two distinctly different designs of carburetor, one type that the model A uses that has potential risk of engine damage, and the other one that does not, plain and simple facts.
It won't destroy the engine, but it will run reluctantly. That's why there are the conversion instructions, which are shown and documented in #19.

I may have discovered and replicated them many years ago here in this forum or in some an other American publication. These instructions also shows the difference between the two factory-modified carburetors.


When a filter attachment is installed, the float chamber is/should not vented to the atmosphere, but rather by the (slight diference) vacuum in front of the carburetor's inlet.
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Old 03-15-2026, 04:24 PM   #37
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Default Re: Ditched the "Air Maze"...

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That's how it looks. And then the engine runs perfectly with filtered air.
in your close up photo with the vent tube from the air intake.
Is there a specific location for that tube to enter the carb or can it go in anywhere above the fuel level in the bowl?
And, is there a specific size for that tube?
And, do you think that set up would work with an air maze filter?

thank you
OU
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Old 03-15-2026, 04:30 PM   #38
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Default Re: Ditched the "Air Maze"...

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When a filter attachment is installed, the float chamber is/should not vented to the atmosphere, but rather by the (slight diference) vacuum in front of the carburetor's inlet.
If we look at a Stromberg 97, the float bowl is vented to the atmosphere and were ran with air filters... so is the difference in the jetting?
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Old 03-15-2026, 05:25 PM   #39
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Default Re: Ditched the "Air Maze"...

The good, the bad, the ugly – I know, like everyone else, I think?


The tube fits into the original vent channel, which I've marked in blue. The vertical hole at the top must be sealed with a short plug (green).
The tube should be as thin as possible; I used 3 mm copper on the outside, it is less than about 1.5 mm on the inside. I glued it in place with your JB-Weld adhesive.

The filter type doesn't matter, as the tube compensates the actualy pressure equalization. This is also important because of the increasing dirt buildup, which increases the pressure difference.


This modification only applies to the Zenith 2 type. Because I have no experience with other carburetors.

I did not change the jets. The engine runs a little bit more ritch. That you can compensate it with the inner turning knob. About +/- 15 degrees. And idle screw.

It's midnight in central Europe, have a good night.
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Old 03-15-2026, 06:56 PM   #40
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Angry Re: Ditched the "Air Maze"...

have you ever seen a Model A flood and soak the filter and when the engine baack fires, you now have a fire that you would not have if not for the air maze filter
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