How Come The Switch From Generator to Alternator...?

I get asked quite often why the car companies switched from generators to alternators, and who did it first. To answer the first part of the question you need to understand how a generator, and an alternator each make electricity. I will try to explain those differences without making your head hurt...to much. As to who introduced alternators first it was Chrysler in 1964, with everybody else following suite the next model year. When you are finished reading this entry you should have a good basic understanding of why the switch was made from generator to alternator.

The Generator...
The generator has a single set of windings used to generate electricity. All of the electrical current made by the generator passes thru the two carbon brushes that ride on the commutator end of the armature.

Because there is only a single set of windings in a generator the output is limited at idle and low rpms, and the overall output is limited by the size of the field coils and the rest of the internal parts. Spinning the generator faster at higher rpms (above factory recommended rpms) will not increase output (will actually reduce output) because the brushes will begin to lift off of the commutator.

The other thing that happens is the generator overheats from excessive voltage, which causes the solder to melt that holds the segments onto the armature. When that happens the segments will come loose... bind up with the field coils and your generator is toast.

In the old days they called this..."throwing the solder out of the generator..." The same can happen when you adjust the regulator to increase output above the factory settings. The generator will overheat the solder will melt and you know the rest. You have caused more harm than good!

It also makes sense that the two biggest wear items on a generator are the brushes and the bearings on either end of the armature. When both are ignored either the brushes will wear down and become short enough that they no longer make good connection with the commutator or the bearing (in some applications bushings) wear out and the armature no longer runs true between the field coils. The armature can then rub on the field coils, damaging both the field coils and the armature. That means you would have to replace both the armature and the field coils...if you can find them!

Finally...new or rebuilt generators often suffer from improper installation. Mechanically, the installation is straightforward but electrically, things are a little more complicated. When the generator is removed from the vehicle for service there is residual magnetism stored in the pole field coils. The polarity of the generator is determined by the direction the current was traveling in the field coils when it was removed from the vehicle.  If... during rebuilding and testing process the current is caused to flow in the opposite direction, (improper testing procedure) the pole shoes will change polarity.

If the generator is then installed on the vehicle, (and the generator not polarized) the reversed polarity will cause the electrical current from the generator to flow in the wrong direction, damaging the regulator (you would be sending positive ground current to your negative ground regulator) and discharging the battery when the car is left overnight. Therefore, all generators must be polarized after installation, and before running the car.

The Alternator...
As we discussed earlier...generators produce direct current which is what all automotive electrical systems run on, even today. By contrast alternators produce alternating current and that current is converted to direct current. It has to do with efficiency... read on!

Alternators have the big advantage of producing a greater amount of current at low speeds as compared to a generator. In an alternator, the "field" windings are placed around the spinning central shaft rather than on "shoes" as in the generator. Two iron pole pieces, cast with "fingers" cover the field windings, and the fingers are interfaced.  The fingers on one pole piece form the North poles and the fingers on the other form the South poles. This assembly is called the ROTOR.

Surrounding the rotor are a series of windings around laminated iron rings, attached to the alternator's case. This assembly is called the STATOR. The engine's crankshaft spins the rotor inside of the stator.

Direct current from the battery is fed through into the rotor's field coil by using brushes rubbing what are called slip-rings. One end of the field coil is fastened to the insulated brush, while the other end is attached to the grounded brush. As the pole fields pass through the stator, current is electromagnetically produced (just like in a generator) but since the rotor is composed of alternating North and South poles the current produced flows in opposite direction every 180-degrees of rotation. In other words, the current is "alternating."


Why is this more efficient? Because the stator windings are made up of three separate windings. This produces what is known as three-phase alternating current. When only one winding is used, single-phase current results (like in a generator). In effect, the alternator produces three times the current of a generator for the same effort on the engine's part. Also, alternators are considerably lighter and smaller than generators and can produce a greater amount of electrical current to cover increased electrical loads.

Converting Alternating Current To Direct Current

Your antique vehicle's electrical system including the battery run on Direct Current also known as "DC" current. The alternator produces alternating current known as "AC" current. Using what are called "diodes", the alternator's electrical output is "rectified" or changed into direct current.

This is done by passing the alternating current thru silicon diodes. Diodes have the ability to allow current to flow readily in one direction only, stopping the flow if the direction reverses. Multiple diodes are arranged in alternators so that current will flow from the alternator to the battery (in one direction only, creating direct current) Diodes are a solid-state device which means they have no moving parts.

The Voltage Regulator...

Like the generators that came before them... most early alternators relied on a voltage regulator that was mounted on the firewall. In the 1970's those regulators became solid state which meant that they no longer had any moving parts to wear out.

The problem with "external" regulators, those regulators mounted away from the alternator, is one of communication. There is often a slight delay in getting the message delivered between the two parties. Dirty or corroded connections along with pinched or broken wires are two common problems that come about with age.

In 1973,  Delco introduced an alternator with a solid- state regulator build inside of the alternator. This increased reliability of the charging system greatly. There was instant response from the charging system and no more broken, pinched, or corroded wires.

When I started building alternators back in 1985 I designed my alternator using the internal regulator Delco design. It makes for bullet proof reliability. I designed my own stator and rotor so my alternator would begin charging at 300 engine rpms instead of the 1200 rpms (which was the idle speed of most engines when alternators were introduced in the mid 1960's).Most antique vehicles built before 1955 have idle speeds of 400 to 600 rpms.

Now we have the best of both worlds. You can install either a Fifth Avenue 6-volt or 12-volt alternator (remember there was no such thing as a 6-volt alternator until I came along)  and have a reliable charging system with minimal "bolt -on" changes to your antique vehicle. You will gain brighter headlights, easier starting, and no more dead batteries. It doesn't get any better than that!

A Brief History Of Automotive Electrical Systems...
We have Allesandro Volta to thank for inventing the automotive storage battery in 1796. He had no idea at the time, that he was inventing what would become a significant part of the modern automotive electrical system. Volta made his discovery 89 years before the first car was offered for public sale. It would be another 25 years before the storage battery would even get a passing acknowledgement from the automakers.

Between 1885 and 1910, most cars and trucks that had gasoline engines did not need storage batteries because they had no accessories that required electricity. Ignition was powered by a magneto, which made its own current. In the rare event that additional electricity was needed, it was provided by a dry cell battery.

By 1911, storage batteries had attained a degree of reliability by being able to hold a charge for 30 days or longer. Once discharged, a storage battery could be recharged and put back into service, unlike dry cells, which were discarded. This degree of reliability was due in large measure to research and development done by the electric car industry, which needed reliable batteries so that their electric vehicles could compete with gasoline models.

The few gasoline car manufacturers who adapted the storage battery, began looking around to see what else they could do with the excess current the storage battery provided, and found electric lights.

1898 Columbia Electric Car 

The first electric lights were introduced on the 1898 Columbia. This was an electric car powered with storage batteries. Manufacturers of vehicles with gasoline engines typically used another way to produce light. It was the Prest-O-Lite lighting system, introduced in 1904. It was a steel cylinder containing pressurized acetylene gas that was fed to headlamps and ignited by flame.

With the adoption of storage batteries the automotive manufacturers then revived the dynamo, which had been around for some time. (Today we call the dynamo the generator, but in those early days most called magnetos were called "generators.") The battery then didn't have to be taken out of the car every month for recharging.

A problem encountered with the early dynamo-equipped electrical systems was battery overcharging. That problem was soon resolved with the development of a variable speed voltage regulator developed by Delco Company. This new voltage output regulator was first used on the 1912 Cadillac, which displayed another feature that took the auto industry by storm..." the self-starter."

1912 Cadillac Electric Starter

Once they adopted the self-starter, auto manufacturers had to adopt the battery/generator system to work the starter. However, the system put out a much more current than the starter, lights and horn needed. The car manufacturers soon realized they could harness this excess current and use it for the ignition, thus making the magneto obsolete.

Self-Starter Beginnings...
The self-starter came about by accident -- literally. In the winter of 1910 on a wooden bridge on Belle Island Mich., a Cadillac driven by a woman stalled. Not having the strength to hand crank the engine herself, she was forced to wait on the bridge in the cold until help arrived.

In time, another motorist, also driving a Cadillac, happened along. His name was Byron T. Carter, and he was a close friend of the head of Cadillac, Henry M. Leland. Carter offered to start the woman's car, but she forgot to retard the spark and the engine backfired, and the crank flew off and struck Carter in the face, breaking his jaw.

Ironically, moments later another car carrying two Cadillac engineers, Ernest Sweet and William Foltz, came along. They started the woman's car and rushed Carter to a physician, but complications set in and a few weeks later Carter died.

Leland was devastated. He called a special conference of his engineers and told them that finding a way to get rid of the hand crank was top priority. “The Cadillac car will kill no more men if we can help it," he announced.

When the Cadillac engineers could not come up with a workable solution, Leland invited Charles F. Kettering and his engineers at Delco (still independent of GM) to work on a solution. Delco presented a working device in time for its introduction in the 1912 Cadillac models.

The Kettering Solution...
Kettering's device was a combination starting motor and generator, equipped with an overrunning clutch and reduction gear. Gear teeth engaged the flywheel to provide a reduction of about 25 to 1 between the starting motor and crankshaft, allowing sufficient torque to crank the engine successfully. General Motors brass didn't trust the new system at first, and demanded a backup magneto and hand crank.

As public confidence in the reliable battery/generator/self-starter system soared, it soon replaced the magneto in all General Motors cars. General Motors enjoyed a sales boom, and the remainder of the auto industry soon adopted the system. Of the 462 models shown at the 1911 New York Auto Show, only 19 had battery/generator systems, and they all had backup magnetos. Of 119 makes displayed at the 1924 New York Show, 110 had storage battery/generator systems and self-starters.

Other Electric Milestones...
In 1939, the first sealed-beam headlamps were introduced which made for much safer driving at night. That was followed in 1949, by the combination key operated ignition and starter switch which was introduced by Chrysler and eventually be adopted by all of the manufacturers.

Prior to 1949 on most vehicles, the starter was operated by a separate button on the dash or by a button on the floor above the accelerator pedal. Starting a car with the floor-mounted starter button was sometimes a challenge: your left foot was on the brake pedal, heel of your right foot on the accelerator, and the toe of your right foot pushing on the starter.

That was a lot going on at one time... especially if you were starting out on an incline. We truly have come a long way from those early days.

The Delco Company...
 The Dayton Engineering Laboratories Co. (Delco) Company was founded in Dayton, Ohio, by Charles Kettering and Edward A. Deeds in 1909.

In 1918, General Motors (GM) acquired the United Motors Company which had been formed several years earlier by William C Durant to house several prominent parts manufacturers, including Delco, Dayton-Wright, and the Dayton Metal Products Company.

All of these latter companies were associated with Charles Kettering, Edward A. Deeds, and Harold E. Talbott. Kettering became vice president of General Motors Research Corporation in 1920. He held the position as head of research for GM for 27 years.

Delco Radios...
In 1936, Delco began producing the first dashboard-installed car radios.  Based in Kokomo, Indiana, Delco Electronics employed more than 30,000 at its peak.

In early 1956, Delco developed a transistorized hybrid signal-seeking car radio, which used both vacuum tubes and transistors in its radio's circuitry. Transistors were used to replace the radio's audio output vacuum tubes and also the vibrator. This transistorized hybrid radio was available as an option on the 1956 Chevrolet Corvette car models.

In 1957, Delco produced an all-transistor signal-seeking car radio and was available for the 1957 Cadillac Eldorado Brougham car models. Delco became part of the General Motors Delphi Group in 1997.

Delphi Automotive traces as it's history back to the New Departure Bell Company, founded in Bristol, Connecticut, in 1888 to manufacture the earliest known doorbell-ringing device. The company's talent for innovation soon extended to transportation, with the 1897 introduction of the first bicycle coaster brake.

Other Delphi predecessors have been involved in automobile lighting since 1906 and manufacturing wooden auto bodies beginning in 1908.

In 1908, Albert Champion, who had been making spark plugs in America since 1899, joined Buick Motor Co. to make spark plugs in the AC Spark Plug Division, which was acquired by General Motors founder Billy Durant in 1909. Durant acquired Dayton Engineering Laboratories, which would become Delco, in 1914.

Other pre-Delphi innovations included the Ring Terminal, developed in 1930; the first car radio (1936); the first radio with mechanical push-button presets (1939); and mechanical power steering (1951).

As Paul Harvey used to say at noon everyday..."and now you know the rest of the story..."

Radio Antenna 101…How They Work, How to Troubleshoot Them.

How exactly does a car antenna work anyway? When you get that annoying background buzz in the radio speakers of your antique or classic vehicle..., how do you determine if that buzz is coming from the radio itself, or from the antenna, and once you figure that out, how do you fix the problem?

Most late model radios and modern antennas are a cut and dried event. For this class, I am talking about the factory radios and antennas found on cars of the 1940's through the 1970's.

Many of us want to keep our original radios and have them restored. but it is no fun if the radio does not work as it is supposed to once it is back in the vehicle.

First a little history. The "stick" or "fish pole" antenna that all of us from the "older" generation know best, first appeared on cars around 1937 about the same time that all metal roofs became popular with car makers. Before 1937 the roof insert of most cars were made up of wooden bows with the headliner tacked to chicken wire that was nailed to the wooden bows.

In the early days automakers used the chicken wire in the roof insert as the radio antenna. By attaching a shielded wire to the chicken wire in the roof insert then routing it over along side of the windshield post, the auto manufacturer could advertise the car as being "wired for radio".

A cool custom trick during the 1940's era was to use the side mount spare as a radio antenna. All you had to do was insulate the metal parts of the car body from spare rim. Next, up attach a shielded wire to the spare tire rim. The tire rim then became the radio antenna. If you had dual side mounts, you could have dual radio antennas. How cool was that!

During the 50's if you were really, really, sneaky, you could insulate the trunk hinges and attach the antenna wire to the trunk lid. Then the entire trunk lid became the car antenna. Who would ever suspect that the entire trunk lid was your car antenna?

No matter what part of your car becomes the antenna, the "antenna" must be tuned to your radio and the lead-in wire must be well grounded at both ends just as if you were using a conventional stick antenna. If you have a poor ground or a loose connection, you radio is gonna have poor reception... guaranteed.

If you are getting a lot of ignition noise in your radio, the first place you should look is the antenna. There are only two ways engine noise can get into your radio, from the battery powered "hot" wire, and from the antenna. The obvious way is through the hot wire but most radio manufacturers took care of that by installing noise filters inside of the radio.

So how do you determine if it is the radio, or antenna that is at fault? It's simple...just tune in the radio on AM band to the noisiest spot (which is usually on the upper 1400 kc part of the dial). Now reach down and unplug the radio antenna from the radio. If the noise disappears or is greatly reduced, you have found the source of your radio noise…the antenna. In most all cases, the cause of engine noise in the radio is the result of a poor ground at the antenna end of the cable.

Some of us (we know who we are) never had any radio problems until we painted our car. That is because we spent more time and effort than the factory did priming and painting places that were never painted at the factory. Among the places we painted was underneath side of the fender where the antenna base mounts to the fender. Because paint is an insulator, the antenna is no longer grounded, at the antenna base. No ground, No Elvis. Simple, as that.

To make your radio work again as it did before you need to restore the metal to metal contact on the underneath side of the fender. A tooth washer will help insure that you have a good solid metal to metal ground connection on the underneath side of the fender. While you are tuning up things, you might as well trim the antenna to the radio and the car body.

Antenna Trim Adjustment...
The antenna trim adjustment has a big effect on how well your radio works and how many stations your radio will receive. The trim adjustment also helps to determine if the stations will fade in and out during your favorite song.

The Trim Screw Location Of a 1957 Chevy Car Radio

The Trim Screw Location On The Outside Cover of The Radio

Adjusting the trim is simple and many of the radios built after 1960 have a thumb screw so no tools are required. To adjust the trim tune the radio to a weak station at the top of the AM band (usually around 1400 kc) then turn the trim thumbscrew in and out until the station is the loudest. Next, gently tighten the thumbscrew and you are done.

On earlier radios, the trim screw adjusts with a small flat, screwdriver. The owner's manual will show you where the trim screw is hiding. On some early radios I have found them hidden behind the volume knob. They were pretty sneaky when it came to hiding the trim screws in the early days.

One, final thing. The round ball on top of the metal car antenna is there for what purpose? A) protection from the sharp end. B) a decoration. C) static- discharge?

If you said static discharge, you are correct! While you are driving down the road static discharge builds up and collects on your radio antenna. Without the ball on top of the antenna the static will continue to collect until eventually it forms a visible ball of static sparks known as a "corona discharge" in radio speak. This static discharge will travel through your radio antenna wire causing that annoying popping sound you hear through the speakers on a dry cold night.

Conelrad Symbols on a Radio Dial
Oh, I know someone will ask…the Conelrad symbols, (the little triangles that appeared on car radio dials during the duck and cover days of the early 1950's...) they first appeared on Studebaker and Chrysler vehicles beginning in 1954. Ford included them beginning in 1955 as did Hudson and Mercury. GM and Packard included them starting in 1956. They were there to tell you where to tune your radio in case of a national emergency, like a nuclear attack.

Now you know the basics of how a radio and the antenna are designed to work. Some simple adjustments will keep you and your radio in tune and singing to Elvis and Hank Williams.  Enjoy!!

Psst...Wanna Buy A Tucker Car Radio...?

Preston Tucker had every intention of putting his cars into production. His goal was to produce 100,000 cars his first year. As was standard practice in the industry Preston ordered materials, especially long lead items, well ahead of scheduled production. Motorola was the company selected to manufacture the radios for the Tucker cars. Motorola geared up and made upwards of 10,000 Tucker Radios in anticipation of a brisk sales year.

As we all know, only 51 Tucker cars were built and all 51 were equipped with radios. So the burning question...what happened to all of those extra radios...?

In the early 1950's the assets of the Tucker Car Company were liquidated. The McGee Radio Company of Kansas City Missouri bought the entire inventory of nearly 10,000 leftover Tucker Radios for the modest sum of a dollar each. They began selling the radios as aftermarket add-on radios new in the box with antenna for $20.00 each.

Then in 1955 the car manufacturers switched to 12-volt electrical systems, thus making the McGee radio kits nearly obsolete (with just a few hundred sold via mail order), as all of the Tucker radios were 6-volt radios. Sales of the Tucker radios slowed to a trickle. With hundreds of radios still stored in their warehouse in Kansas City, a fire erupted and the entire warehouse was completely destroyed, including the balance of the Tucker Radios.

Many people assume that the Tucker Radios are quite rare. But we know every car that Tucker built... all 51 of them, came with a radio. So clearly there are way more spare Tucker radios left than there are Tucker cars to install them into.

Some projects are just doomed from the start and do not get better as time goes on, but instead go from bad to worse. When your next project seems doomed and you think it can't get any worse...just remember the Tucker radios. There is always a project somewhere, worse off than yours...

Keeping Cool..When Did Air Conditioning Become An Option in Automobiles...?

This car which served as a Taxi for the wealthy in New York City was one of the first to be air conditioned in 1933. The biggest problem with this early system was that there was no way to control the output, the compressor ran all of the time so there was cold air output all of the time. This system was considered to be one of the first applications of air conditioning in an automobile, long before it was common in most houses. The inventor of this system lacked proper backing, funding, and marketing skills. As a result he was only in business a couple of years. The cost to add this system to an automobile was in the neighborhood of $450 in depression dollars... way above what the average car owner could afford.

Other Options For Keeping Cool...

Keep in mind that air conditioning in homes was not common until after World War II. Window air conditioners first started to appear in the late 1930 but were very costly and were mostly bought by the wealthy. "Swamp Coolers" worked much like the "Car Coolers" described above and were mainly found in the desert southwest and locations where there was low humidity. Central air did not become common in houses until the mid 1960's.

Most of the Air conditioning units sold and installed in automobiles beginning in the 1950's's were aftermarket units. The big three Ford, GM, and Chrysler considered air conditioning to be a limited market confined to the south and was not worth the development costs. Not surprising Texas was the home to the majority of aftermarket air conditioning manufacturers because they had the three things needed, heat and humidity, plenty of customers, and money.  

The Texas companies had a monopoly for about 25 years, before the OEM companies realized that air conditioning was an option the public wanted, and would pay for. The Texas companies such as Mark IV sold thousands of aftermarket air conditioning units. They established hundreds of "authorized" installation centers throughout the southwest and even up into the eastern part of the United States.

In the 1970's the aftermarket companies even picked up contracts to install air conditioning units in newly imported vehicles from such manufacturers as Toyota and Datsun, who had the air conditioning units installed as soon as the new vehicles were unloaded from the ship, and before they were delivered to dealers. The Texas aftermarket manufacturers even engineered a kit for the Volkswagen Beetle. 

When the OEM manufactures finally caught on, the honeymoon was over, and the Texas companies sold out, consolidated, diversified, or went bankrupt and were liquidated. It is interesting to think about how three main aftermarket companies from the south were able to advertise and install such a popular automobile accessory for more than 25 years, before the OEMs got wise and finally began offering air conditioning as a factory installed option.

Can I Add Air Conditioning In My 6-Volt Antique Vehicle...?

I often get the question from customers..."Can I add air conditioning to my 6-volt antique vehicle...? The answer is yes and no... let me explain. The air conditioning unit requires a blower motor and it does not matter if that blower motor is 6-volts or 12-volts. The actual air conditioning system does not require any electricity. The problem is with the compressor. 

Most early air conditioning units from the 6-volt era had no clutches on the compressors so the compressors ran all of the time. So that means there is also no temperature controls for the air conditioning units... they had a constant output all of the time. The only way to shut them off was to stop and remove the belt from the compressor that was driven off of the engine. 

If you are running a Fifth Avenue 6-volt alternator you have plenty of electrical output to power the extra blower motor(s). Again...the compressor clutch is the issue. Early design air conditioning compressors required 4 to 6 horsepower from the engine. You might be old enough to remember that when the air conditioning was turned on, the idle speed of the engine was automatically increased 600 to 800 rpms to compensate for the horsepower load of the compressor. 

The modern air conditioning compressors are much more efficient than the compressors were... even in the 1980's, (they are also smaller in physical size) and they require about a third of the horsepower that the early compressors did. I have had a few customers do some research and find a modern 12-volt compressor clutch that would engage with voltage as low as 7.0 volts. The output of a Fifth Avenue 6-volt alternator is 7.5 volts so it worked. If you want to do something bad enough you can usually find a way. 

But generally... because most all of the 6-volt compressors used in the early air conditioning units had no clutch, there is no control of the output. It would also be really difficult to find a working 6-volt air conditioning compressor. If you want to add air conditioning to your antique vehicle, it works best in most applications, to upgrade the electrical system to 12-volts. It is not difficult, I help customers do it every day. At least now you know how everything works.

Henry Ford And Air Conditioning

This Henry Ford story is not true of course, but it has been associated with automotive air conditioning since the 1950's and a lot of people have been suckered in, and believe it to be true. Now you know better... but you can still have a little fun at the next car club meeting telling this story.