Cast Iron Brake Drum Info
by Lynn Sondenaa, Volcano ‘A’s
This information is about reproduction cast iron brake drums. Gray cast iron is what most manufacturers use to produce cast iron parts. It has been in use since the Model ‘T’s & Model ‘A’s came into existence. Even the reproduction cast iron drums made in China are gray cast iron. Some cast iron drums are advertised as nodular iron. Nodular iron is gray cast iron which has small amounts of magnesium added to form a premium cast iron. Nodular iron is also known as spheroidal or ductile iron. It has excellent ductility, higher tensile strength, and better corrosion resistance than gray cast iron. Ductility refers to the ability of metal to stretch, bend, or twist without breaking or cracking. Tensile strength is the property in metal which resists forces acting to pull the metal apart. Corrosion is the wasting away of metals by slow gradual combination with other elements and chemical compounds. You may use this information to make an informed decision before purchasing your new re-production cast iron brake drums!
Script ‘A’ News December 2019
Technical Tip on Threadlocks
by Lynn Sondenaa, Sandy, Oregon
To prevent nuts, bolts, and machine screws from loosening due to vibration, the following items can be used. The most common is a lock washer. It is an incomplete circle that has a twist that is flattened when tight. A spring washer is made from spring steel with a slight crown or twist. When tightened the crown is flattened and this pressure holds the fastener tight. Star washers have little fingers that dig into the surface to hold tight. They are made in internal and external styles. Self-locking nuts have a nylon insert to keep them tight. Their disadvantage is that they should only be used once. A liquid thread-lock can be applied to threads. Loctite is a popular brand. Thread-lock liquids are made in different strengths. I use Loctite blue 242 medium strength. The fasteners can be removed with normal tools after it has cured, but it will hold tight. The high strength type takes a lot of work to remove, as it is designed to be permanent. This information should prove valuable when working on the Model ‘A’.
Volcano View September 2013
OF THE FUEL CHANNELS IN THE ZENITH CARBURETOR
Jim G - June 2013 (Editor’s Note: From the Archives!)
The Zenith carburetor was an excellent choice for the Model ‘A’ Ford. Henry’s highly trusted design engineer, Harold Hicks, selected the French design and adapted it to meet Henry’s demands for the Model ‘A’. This is not a technical tutorial on the Zenith carburetor, just an effort to provide a basic understanding of the fuel flow channels.
Hopefully this will aid someone in the future when issues from contaminants cause reduced performance and require a little TLC to “clean out” the carburetor. Unfortunately, “stuff” does get into the fuel system to mess with the fuel flow in the jets! Fuel arrives in the Zenith carburetor fuel bowl through the “screen” filter in the top casting above the fuel bowl. Near the bottom of the fuel bowl there are three outlets for the fuel.
1.) Near the back side (engine side) of the carb is an opening that allows fuel to flow directly to the main jet! This is a straight shot that feeds this jet only!
2.) In the middle of the three openings, is the Comp Jet. It is the small brass screw with a hole in it. This jet controls/meters fuel flow to the Secondary Well. The Comp Jet is calibrated to provide a measured feed for both the Cap Jet and the Idle Jet. Even though both jets drink from the Secondary Well, they do so at different times as engine demands change. They do not perform/serve at the same time.
3.) Last is the opening on the front side of the fuel bowl and provides fuel to the GAV (gas adjusting valve). The GAV function is to bypass the Comp Jet when “extra fuel is required” for special driving conditions. It increases the fuel available for the Cap Jet to meet high fuel demand conditions (e.g., the heavy engine loading of hill climbing). Well, that does it, not really that complicated when you think it through. So, if you are really having a carburetor/fuel problem, you now have an appreciation for where to start looking for the blockage. I have one further comment about the Idle Jet and the Cap Jet! They not only do not feed at the same time from the Secondary Well, their fuel input requirements are significantly different. The Idle Jet flow requirement is about one quarter (¼) that of the Cap Jet (46 vs. 165 cc/min). Thus, opening or closing the GAV when the engine is at idle rpm, should have no affect! If it does the carburetor is not feeding through the idle circuit. The idle jet, the smallest of them all, is likely the problem.
(All the above assumes no vacuum leaks)
The Steering Column March 2021
No More Blind Spots
(from USAA Magazine, May/June 1998, p48)
To reduce the blind spots in your sideview mirrors (and lessen your chances of an automobile crash), make sure your mirrors are properly adjusted. Here’s how: For the DriverSide mirror: Place the left side of your face against the driverside window and adjust the mirror so that you can barely see the left side of your car. For the PassengerSide mirror: Sit in the center of the front seat (or lean as close to the center as possible) and adjust the mirror so you can barely see the right side of your car. Approaching vehicles should be in your sideview mirrors before they leave your rearview mirror and in your peripheral vision before they leave your sideview mirrors.
A handy item to keep under your Model ‘A’ Seat
by Bob Toms
This is a simple device that will help you diagnose trouble in your electrical system and, in some cases, offer a temporary solution to get you home: a simple length of wire, about 500mm (20 inches) long, with alligator clips attached to each end. An easy do-it-your-self item!
· Connected across the terminals of the junction box, it can bypass a faulty ammeter.
· Use a longer bolt in the distributor terminal of the condenser. Connect this to the red coil wire using the by-pass wire and you can energize a defective ignition switch or faulty armored cable.
· If the cut-out contacts fail to close, you can by-pass the cut-out to charge the battery. · If the cut-out is stuck closed, the by-pass wire can be used to ground the generator output terminal.
· It can be used to test resistance (or voltage loss) in the horn and lighting circuits by by-passing switches and connectors.
· For that matter, it can be used to test contacts and wires hidden in body work or in con-duits.
FIVE MINUTES TO MAKE COULD SAVE YOU HOURS TO FIX!
Thank you to Andre Millar, in South Australia’s Model A Torque.
Technical Notes: Points to Ponder #2 on the Model ‘A’
by Lynn Sondena, Sandy, Oregon
Model A engines like “hot” spark plugs.
• To locate exhaust system leaks, squirt a small amount of kerosene into the air intake of the carburetor while the engine is running. Leaks will be visible from the black smoke appearing at the leak.
• Use zinc chromate primer, it helps to prevent rust.
• Torque spark plugs 34 to 38 pounds.
• Backlash is the play between the teeth of two gears which are engaged.
• Advanced spark is igniting the fuel mixture before Top Dead Center.
• Retarded spark is igniting the fuel mixture after T.D.C.
• Zenith float level adjustment is done by adding or subtracting washers underneath the float valve.
• Did you know that the float valve fiber gasket is the same size as the distributor shaft sleeve fiber washer? Snyder’s number A-12181 or Mac’s #A-12194.
• A front-end shimmy is usually caused by loose tie rod ends, or drag link ends. It can also be worn ball studs on the steering arms and pitman arm.
Volcano View May 2013
Tips from Down Under
Found in a newsletter from New Zealand, Canterbury Chapter Brake Rod AntiRattlers
Correct installation: Disconnect rear rod clevises, loosen locking nuts, and remove clevises; slide anti-rattlers over rods so that they are pushing against donuts toward rear of car, bolt to bracket on radius rods; reinstall clevises and locking nuts.
Fronts are different - anti-rattlers slide on from eye end of brake rods, so disconnect from cross-shaft arm at center of car, slide anti-rattler on, bolt to bracket; reconnect rod at center. You may have to enlarge the openings in the front anti-rattlers so they will slide over the eyes.
Oil Loss: A quart of oil is 36,500 drops of oil. A normal engine in the ‘60s used 1/1100 of a drop on every power stroke (1 quart every 1000 miles was normal back then) and if an engine drips one drop every 50 feet, and it doesn’t matter how fast you’re going, (think about it) the engine will lose 1 quart in 300 miles. They used this to illustrate that a drop was actually much higher consumption than a burn!
Burning Points: Loose connection somewhere between cutout and battery, causing voltage to go berserk and burn points. Check connections at: cutout, junction box, ammeter, added fuse holder, (if any). Remove both forward 3/8” nuts on junction block and tighten both of the 3/8” nuts inside the box. Be sure ground system is good by clipping test light to gearshift, put point to middle of + +battery post, step on starter with key off. No light = good grounding. Light on = poor ground connection somewhere. Feel each connection for being HOT! Loose connection = HEAT. In regard to the condenser. The job of the condenser is to take the brunt of power from the coil when the points break to keep the points from sparking/burning. In modern times in every other application other than automotive we call them capacitors.
Painting Fuel Gauge Figures : Has the black paint in the fuel level markings disappeared?
1. Clean the curved sector with the markings really well.
2. With a tiny brush or toothpick, fill the letters with fuel-proof paint. I use a glossy black epoxy spray paint. It will take 2 or 3 coats. Do no worry about putting on a bit too much.
3. When the paint is really dry, wet-sand the sector with something like 600 grit paper to remove all the overflow paint. Gas Tank Welting: One piece goes from one side of the tank, all the way to the other side, starting and ending at the rear edge of the hood. At the sides, it runs between the cowl and the tank, and in the center, between the tank and that strip that runs right under the windshield. There are various tricks for getting the welting to stay in place. You will need to pre-cut holes or slots for the bolts that hold the filler strip and tank to the dash rail. You will also need to make some notches in the flat part of the welting to help it go around the corners. The last inch or so, where it passes under the cowl band, has the core removed, and it serves as an antisqueak under the front top corner of the cowl.
Gearbox Shielded Bearings:
Main drive gear and main splined shaft cannot be perfectly shielded and shielding may not be a smart thing. Ford designed parts to take advantage of function. The front bearing does not matter much. It faces up and there is the throw-out bearing sleeve preventing oil from going anywhere. The rear bearing is open to the U-joint. The grease forms a packing and the oil that leaks past will get into the U-joint and then back to the speedo gear and the drive shaft bearing. So why seal the rear bearing.
Script ‘A’ News, December 2020
GREASE YOUR SPEEDOMETER CABLE
How long has it been since you lubricated your speedometer cable? Lubrication of the speedometer cable must rate among the most overlooked, and definitely the messiest, maintenance item on the Model ‘A’ Ford.
While driving, the speedometer cable rubs against the speedometer cable housing, creating hot spots where it rubs. A good lubricant reduces the friction, increasing speedometer cable life and reducing noise. White lithium or black molly are good lubricants.
Harley Davison also makes a good speedo-cable lubricant. To lubricate the cable, remove it from the housing, and apply grease to the length of the cable as you put the cable back into the housing. You only need to disconnect one end of the speedometer cable housing to accomplish this task, and if working over your head is not a problem, disconnecting the speedometer housing from the drive assembly on the torque tube will allow access to the speedometer cable and leave your instrument panel untouched.
By Jim McPherson - Aiken A's