What are some of the counter intuitive things you have learned about a Model A?

[shew01]

This post may be helpful to folks that are new to Model A’s.

What are some of the counter intuitive things (and their fixes) you have learned about a Model A? For me, here are some of the things that I didn’t expect and cost me time figuring them out. I’m still fairly new to Model A’s. Please correct me if I get any of the following wrong.

1) If you have the distributor cap off and the metal linkage rod disconnected, you can accidentally rotate the upper distributor plate so far that it may pop up (without your noticing it) out of its groove and disconnect itself (electrically) so that you will not get 6 volts on the moving point arm when you test for proper voltage.

2) The metal linkage rods that connect the steering column spark lever (on the left side of the steering wheel) and throttle lever (on the right side of the steering wheel) to the distributor and carburetor have ends on them that fit over linkage balls. The linkage rod ends are spring loaded and “stretch” so that you can remove the rods from the balls.

3) I still don’t understand how a metal inner tube valve stem is installed. The tubes appear to ship from the manufacturer with rubberized valve stems.

4) Depending on the distributor, it has at least one manual place to oil it, a sliding tube (oil cup) at the distributor’s base. The "Ford Model 'A' Instruction Book" says the following. "The distributor should be kept clean and well oiled. Put oil in the oil cup at the side of the distributor every 500 miles. Add sufficient oil to reach the level of the oil cup. Every 2000 miles remove the distributor cap, clean the lobes of the cam and apply a light film of vaseline." The theory is, if done properly, the oil migrates up into the upper bushing of the distributor.

As I understand it, an aftermarket modification is a “drilled” cam screw that accepts oil from the hole in the center of the screw, which lubricates the upper distributor shaft. This only works if the upper distributor shaft is also drilled through the center of the shaft and drilled with a hole in the side of the lower portion of the shaft. (Sadly, it is possible for your car to have the drilled cam screw but have a solid distributor shaft. It just depends on which parts were available the last time a mechanic worked on the distributor.)

5) The Model A does not have a VIN (Vehicle Identification Number), in terms of what we call a VIN on modern cars. (VINs were federally mandated in 1954, and the newest Model A is a 1931.) Instead, the Model A has an engine number (also called a serial number for the car) stamped on the driver side of the block (after successful engine testing during the manufacturing process). Ford manufactured engines in bulk and later installed them onto frames as the cars were assembled. At the time of installation, the engine number was copied to the frame so that the engine and frame numbers should theoretically match. However, engines get swapped out of the cars from time to time, the engine number tends to get restamped from time to time, and the number on the frame is not easily visible because it "hides" on the top of the frame underneath the driver side of the cab body. Typically, the frame number is considered the "correct" number. Be aware that, even if you take the body off the frame, the frame number may not be readable because of rust, or some folks say their frame does not have an engine number at all. Usually, the engine number, which functions as a VIN for most DMV purposes (some states may vary), should be on your car title.

This interesting web site (http://www.plucks329s.org/studies/studies.htm) has additional information.

6) If the car has been sitting for years, it’s a good idea to drop the oil pan to clean out the sludge that is likely to be present in the bottom of the pan, on the oil pump screen, and the dipper splash tray. However, be aware that the oil pump can fall out as your remove the pan. Model A parts dealers sell a device that screws into the side of the engine to prevent the oil pump from falling out. If you decide to use your own screw, be aware that the hole has an NPT thread, which is not a standard thread that is likely to be found in your toolbox. The hole is easily stripped with an improper screw.

While you have the car apart, it is also recommended to clean out the valve galley located behind the valve cover and additionally clean the 3 small oil passages located in the rear bottom of the oil galley.

7) The starting sequence is unusual. The "Ford Model 'A' Instruction Book" says to do the following.

Before Starting the Engine

"Be sure the gear shift lever is in neutral position, i. e., the position in which it can be moved freely from side to side. Advance the throttle lever located under the steering wheel (right hand side) about three notches, or until the accelerator pedal moves slightly downward. Pulling down the throttle lever or pressing on the accelerator pedal, controls the quantity of gas entering the cylinders, and regulates the speed of the engine. Place the spark lever (left hand) at the top of the quadrant (the notched quarter-circle on which the lever is operated). This is the retard position. The spark lever regulates the timing of the spark which explodes the gas in the cylinders. Always retard the spark lever when starting your car. Starting the engine with the spark advanced may cause the engine to kick back, and damage the starter parts. After the engine is started, advance the spark lever about half way down the quadrant."

The "Ford Model 'A' Instruction Book" also says the following.

Starting the Engine

"A. Release the lock cylinder by turning the switch key to the right as described on Page 6. [Be aware that this refers to the original Ford "pop out" ignition switch, which may have been replaced with a reproduction switch on your particular Model A.]

B. See that the spark lever is retarded; the throttle lever advanced three or four notches on the quadrant and the gear shift lever in neutral position.

C. If the engine is cold, turn the carburetor adjusting rod one full turn to the left [starting from the full clockwise position] to give it a richer mixture for starting. This rod serves both as a choke for starting and as an enriching adjustment. Next pull back the rod, at the same time pressing down on the starter button with your foot. The instant the engine starts, withdraw your foot from the starter button and release the choke rod, next advance the spark lever about half way down the quadrant. When the engine warms up, turn the adjusting rod back to the right. Never drive continuously with adjusting rod more than 1/2 turn open. (See Adjustment of Carburetor, Page 24.)

When starting a warm engine, do not pull back the choke unless the engine fails to start on the normal mixture as there is a possibility of flooding the engine with an over rich mixture of gas. lf you should by accident flood the engine, open the throttle and with the choke rod in normal position, turn the engine over a few times to exhaust the rich gas."

Apparently, the settings for the spark lever, the throttle lever, and the GAV (Gas Adjustment Valve) vary quite a bit from car to car, and these settings appear to be an "art form," rather than an exact science. Folks tend make strong arguments for the settings that they have found to work for them.

8) The spark control lever (the left lever on the steering column) is not a "set and forget" piece of equipment. The "Ford Model 'A' Instruction Book" says the following.

The Spark Control

"For average driving the spark lever should be carried about half way down the quadrant. Only for high speeds should the spark lever be advanced all the way down the quadrant. When the engine is under a heavy load as in climbing steep hills, driving through heavy sand, etc., the spark lever should be retarded sufficiently to prevent a spark knock."

9) No matter how many books folks suggest you buy, there will always be one that you don't have when someone suggests reading for more information. However, the following books are highly recommended.

A) "Ford Model 'A' Instruction Book" (This booklet shipped with all cars when they were new, and reprints are still available.)

B) Les Andrews' "Model A Ford Mechanics Handbook, Volume I"

C) Les Andrews' "Model A Ford Mechanics Handbook, Volume II"

D) Les Andrews' "Model A Ford Troubleshooting & Diagnostics"

E) "Ford Model A Service/Repair Bulletins Manual 1928-1931" (Reprints are available on Amazon.com.)

F) "Model A Ford Construction, Operation and Repair" by Victor W Page, Post Motor Books

G) "Ford Owners Handbook of Repar & Maintenance" by Victor Page, Floyd Clymer Publications

H) "Model A Ford Restoration Handbook" by Gordon Hopper, Floyd Clymer Publ

I) "Know Your Model A Ford" by Murray Fahnestock, Page Motor Books

10) It is recommended to use the Ford Barn "Search" function as the vast majority of questions/subjects have been previously discussed. Forum members appreciate those who have done some homework before posting.

11) The quest to make one repair tends to lead to making additional repairs along the way, especially if you are new to the hobby. Make sure that you disconnect the battery before making electrical changes. The original Model A did not have any fuses. Add one if your car does not have one. This is an example of a fuse designed for the Model A: https://www.brattons.com/fuse-mount-assembly.html

12) Be wary of new parts. Some are okay, while others are junk. Sometimes even "good" new parts will not be quite the exact size that you need. New mats seem to "approximate" the sizes of the original mats. Metal may need to be filed for hard parts to fit. Most seasoned Model A hobbyists tend to value rebuilt original parts more highly than new reproduction parts (because rebuilt original parts tend to fit and work better than new reproduction parts).

13) Unleaded ethanol gasoline will burn okay in a Model A. Leaded gas was not available when the car was manufactured. However, the alcohol in ethanol tends to collect moisture, which will cause the gas tank to rust. If that rust breaks free from the tank, it tends to clog carburetor parts and possibly score the gas shutoff valve. For additional information, please see http://www.fuel-testers.com/review_g..._products.html.

If your car is so equipped, the sediment bowl, the sediment bowl screen, and the carburetor filter should help keep damaging trash from getting into/damaging the carburetor. Your car may also be fitted with a small "pencil" filter that fits into the fuel shut off valve.

14) The GAV/choke rod connection to the carburetor is unique. (I need some help wording this one--I have never had this apart.)

15) Although the Model A was manufactured without an air filter, several aftermarket air filters are available for the car. Be aware that a Model A carburetor may tend to leak, and the car may backfire from time to time. The air filter is normally mounted close to a hot exhaust manifold and close to potential carburetor leaks. (Actually, some air filters can get soaked by a carburetor leak.) Consider the potential of an engine fire when you are making the decision to add an air filter to your car or continue to use an existing air filter. You will likely see that folks tend to make very strong arguments for and against air filters on a Model A.

16) Carry a fire extinguisher in your car. 90 year old wiring and a leaky carburetor can easily cause a fire.

17) The original fan is made of steel, and it has a tendency to for its blades to crack and break off while the engine is running. Lose fan blades have been known to damage radiators, and they have also been known to "fly" through hoods. If you have an original steel fan, it would be wise to replace it with an aluminum reproduction, which is less likely to break over time.

You should check your fan blade for tightness from time to time. I checked my aluminum fan blade right after the purchase of my car. 4 months and 2000 miles later, a mechanic found it to be wobbly. Whoever installed it did not have it torqued tight enough, and the blade had wallowed itself out on the spindle.

You will likely need to remove the water pump to remove the fan blade. Otherwise, you will likely need to remove the radiator to get to the fan blade.

18) Be aware that breaking loose the upper radiator hose for hose replacement or fan replacement can lead to a hairline crack in the upper radiator tank (likely at the bottom of the inlet neck). Do not be "rough" when removing the old radiator hoses. (Radiator repair shops do not exist in my area. A "good" replacement radiator can easily cost more than $600. The "cheap" radiators can have fitment issues.) Many Model A hobbyists use blue Hylomar gasket sealant on the radiator hose connections so that the hoses will not "weld" themselves to the fittings and make hose removal easier later.

19) When you remove the spark plugs or the distributor, it is wise to use a copper-based anti-seize compound on the spark plug threads and the areas of the distributor that contact the head during replacement. (Be aware that the alignment pin on the bottom of the distributor can seize and cause the distributor to bind during removal.) The anti-seize compound will make later removal of these parts much easier. Use of an anti-seize compound on the spark plugs is especially advisable if you have an aluminum high compression head.

Using a pry bar to remove a distributor can crack the distributor casting. It is possible to break off the distributor inside the head during removal when folks are "rough" with it during the removal process.

Anti-seize compound also works well for clevis pins, especially ones removed for maintenance, like the clutch linkage pin. A mixture of anti-seize and engine oil makes a "paintable" lubricant good for the wishbone ball. It's a good idea to use it on assemblies subject to weather as well. If a bolt and nut can rust, just use some anti-seize compound. It takes a bit longer to assemble the job, but the next time you remove the part (or the next guy does it) you will be glad you did.

20) The rear brake drum deserves its own special section.

A) When reassembling the brake drum on the axle shaft, there may be very thin, conical axle shims positioned between the axle and the mating drum shaft hole. The shims are there to take up wear that has occurred over time. Be aware that the edges of the shims can be razor sharp and sometimes ragged.

B) At least on my car, the axle key can fit into the groove on the axle 8 different ways, 7 of which are wrong. The axle key has a tapered section, and the mating groove in the axle also has a matching tapered section. When assembled correctly, the tapered portion of the axle key should point “down” toward the center of the axle spindle and be positioned toward the differential, not toward the axle nut. Then, the axle key should slide into the matching tapered section of the axle shaft groove. To a new Model A hobbyist, this may look odd, but, as I understand it, this is the proper axle key position.

C) When assembling the drum on the axle, it should be a “dry” (i.e., ungreased) fit, meaning that the axle shaft, shims, and the mating drum shaft hole should all be free of all oil and grease. Brake cleaner can be used to remove oil and grease from the surfaces.

D) After the drum is back on the axle shaft, place the fiber grease seal washer (which was missing on my car) onto the axle shaft first, place the steel washer (I’ve read where this may be missing on some cars) on the axle shaft second, and place the axle nut on the shaft last. Model A parts dealers sell inexpensive replacement fiber washers and steel washers if they are missing on your car.

E) Les Andrews' "Model A Ford Mechanics Handbook, Volume I," page 1-362, says, “Torque the rear axle nut to 125 ft/lbs. Insert cotter pin.” However, opinions vary on that torque value. Most folks I have run across tend to torque the axle nut closer to 100 ft/lbs.

F) If you use shims, the axle nut tends to loosen over time, and you should check the torque frequently.

21) Rear wheel bearing grease seals can be difficult to remove. For other old cars, I have been able to pry the old bearing grease seal "lip" out of the drum with a screwdriver, which usually tears up the the grease seal, but I don't tend to reuse grease seals anyway. However, for a Model A, there is no grease seal lip, because the grease seal is recessed in the back side of the drum by about 1/4" or so.

One Model A hobbyist suggested that I place a piece of cardboard on the concrete garage floor and drop the drum (grease seal side down) a few times to dislodge the grease seal. I tried that for the driver side grease seal, and I gave up after about 30 drops. The grease seal budged a little, but it didn't dislodge. As it turned out, this grease seal was super tight. I ended up digging the seal out with a screwdriver and a claw hammer. Thankfully, I did not damage the wheel bearing. Oddly, the passenger grease seal came out of the drum after dropping it on the cardboard about 5 times or so. What complicated matters was that my driver side rear drum was not the same design as my passenger side rear drum.

Later, another hobbyist recommended drilling a hole in the grease seal and inserting a screw into it to give some leverage for removal. (You will need to be careful not to drill too deep because you won't want to drill into the bearing. You will also want to insert the screw only a couple of turns to avoid marring the bearing.) I didn't try that (since the grease seals were already removed), but that may be worth a try the next time a grease seal gets stuck.

The Model A parts dealers sell a "rear hub seal driver" to reinsert the grease seal properly. For me, it was money well spent.

22) Although the American Model A was manufactured with SAE fasteners, hex screws, and flat blade screws (a while back, I think I read that Canadian Model A's had some square slot screws), the car is old, and lots of repairs have been made along the way, using whatever parts were on hand at the time of the repairs. As I went through my car thoroughly for maintenance, I unexpectedly found some Philips screws and even some metric bolts and nuts, depending on the fastener. If you plan to take your Model A on a trip, it would be wise to take along an assortment of screwdrivers, wrenches, (SAE and metric), and adjustable wrenches.

23) Apparently, it is not uncommon for the shock fill plug threads to be stripped. Model A parts dealers sell replacement plugs. As a temporary fix, you may consider automotive teflon tape or Locktite to keep the plugs in the holes.

Model A parts dealers also sell shock rebuild kits. From what I understand, the shock reservoir cover can rust and be difficult to remove for a rebuild. Model A parts dealers also sell replacement shocks. (Bill) Stipe shocks have a very good reputation for being very good reproductions.