A Reader Responds

Associated-United Engines

Engines still being built today

Content Tools

26 Mott Place, Rockaway Boro, 'New Jersey 07866

The following three articles were written in answer to readers and questions which appeared in the Reflections column in the March 1986 issue of GEM. It is hoped that Mr. Mackey's detailed information will be helpful to other readers.

The first two articles deal with the question from Hugh E. Porter, RR 1, Box 274, Dallas City, IL 62330: 'How many models were made of the small Reo and Continental engines, and where might we locate manuals for same?'

Reo Engines

The Reo 45° bank 1-cylinder engine (cast iron) was made from approximately 1947 to 1958. It departed radically from the accepted designs of the times in which it was built. It is the only small 1-cylinder 4-cycle engine that runs counterclockwise. The cam and valve arrangement was unique (see diagram) and the camshaft was also the sole power takeoff point except for one example that had an extra reduction built in.

These small but strong engines were made with many variations. Some were minor, like a different carburetor or fuel tank. Others were major, such as a change in bore and stroke, or the placement of a recoil starter (with a stainless steel pull cord) instead of the standard 'wrap a rope' setup.

There are 3 major 45° engine types. First, the most common, is the 'regular' 45° engine. This engine was mostly put on Reo reel type lawn mowers, called the Reo Royale (early) and the Reo Runabout (later). I own about 8 of these engines and no two are exactly alike. The later engines almost always had the recoil starter. The second type was still a 45° bank engine, but had an extra gear reduction built into the timing case. This produced a 7 to 1 ratio at the output shaft. These were used on a 2 wheeled garden tractor built by Reo. The third type was again a 45° engine, but this series was placed on its side to power a rotary lawnmower. This mower was also built by Reo. I do not have specific information on the third model as I do not own one (yet); however they were only built during the last two years of the 45° engine's production. The crankshaft was vertical in this model; on all others it was horizontal. I have only seen two examples of this type engine.

In early 1957 Reo began building an aluminum block 4-cycle engine under license to Tecumseh (an engine company still in operation today). This engine looks like and runs like engines still being built today. Also in 1958  Reo began production of all types of gas powered equipment, using the 'new' aluminum engines. I still use a Reo snow blower built in 1959  that my parents bought new that year, that has a 'license engine' in it.

Although the Reo-built 'license engines' look the same as the Techemseh engines built at the same time, they were in fact different, and not very many parts were interchangeable. (A more modern parallel is between the U.S.-built Wisconsin, and the Japanese-built license the Wisconsin Robin engines: the same, yet different.) Some parts are still available for the 'license' engines, if you have the model, type, and serial numbers, from a Techemseh dealer. A good small engine shop should be able to match up a set of points and a condenser for either engine (the 45° will take time), and carb parts should still be around too (although some of the 45° carbs are obsolete for example, the Tillotson carb used on the 45° Model 404). No new parts are available for the 45° engine.

Reo was a self-owned company until 1962 when it was bought out by the Wheel Horse Company. The Reo company still operated as a division of Wheel Horse until it was finally shut down in a consolidation move by Wheel Horse to eliminate competition within the company itself. Reo was ended in 1964.

Continental Engines

The Continental 30° bank 1-cylinder engine was a strong power-plant. A friend of mine has over 50 variations of this interesting engine. The engine started production in 1946 and even with all the variations has remained relatively unchanged throughout the years. The three major changes are as follows:

The first series of engines, the AA Series, had the carb and the intake mounted underneath the cylinder (updraft intake) and had a remote fuel tank (the gas was delivered to the carb with a copper tube from the tank). This series was built from 1946 to 1949-50. It was sold as a general power plant.

The second series, the AC Series, was basically the same as the AA with the exception being that siphon feed carb (with fuel tank directly attached), similar to the ones used on the B&S cast iron engines, was used. The AC Series was built from 1950 to 1955, and was only used on lawnmowers.

The third series, the AU Series, was entirely reworked, although the basic design was unchanged. The carb and intake were now located on top of the cylinder (downdraft intake) and like the early engines, had a separate fuel tank. This series was built from 1955-56 until the late '60's. All models, with the exception of the AC Series, were used on any powered equipment you could imagine (fans, tillers, pumps, generators, David Bradley tractors, etc.)

As an interesting side note, I used to own an AU Series Continental mounted in a scale Midget Racer. It had plenty of power and speed, but the previous owner had found a unique way to radically increase power without major work on the engine's internals. On the dash were mounted two switches, one marked 'boost', the other 'kill'. If you were just riding around the track and you turned on the 'boost' switch, more often than not the engine would just backfire and die. However, if you were running at full speed and power, and then threw the switch, it would feel like someone turned on the afterburners! The machine would literally spin its tires and gain approximately another 20 mph at top end. I did not see anything that contacted the engine in the cart except for an extra wire to the points cover.

Well, I got curious and removed the engine from the cart to find out what gave it that radical push at high speed. I mounted the engine on my 'test bench' (my mom's picnic table) with two seat clamps I borrowed from my dad. On examination I found that the 'boost' switch actually eliminated the point from the ignition circuit, leaving a crude but effective capacitive discharge type of spark control (see diagrams A and B). In a bench test I made, (NOT recommended), at full throttle the engine would make a little over 4,000 rpms before the wires fell off of the switch I had on the table. I didn't repeat the test because of two reasons: 1)I was afraid I'd blow the engine up, and 2) my mom came out of the house to see what the engine was screaming about and was very displeased with my choice of a work bench ( 'No I don't want to hear it go faster!'). It was an interesting project checking that one out. At a later date I did a similar test on another Continental that was in poor mechanical shape; it did explode literally. I don't think it revved any faster, but it blew pieces of metal over the roof of my garage, not to mention the mess it made of my 'test bench'. (You guessed it. It cost me 89 hard-earned dollars to replace the picnic bench.)

Continental Motors was acquired by the Detroit Engine Co. in approximately 1967-78. I believe that the same 30° bank cylinder engine is still being made under the Deco label; however, I don't know if parts are still available.

Special thanks to Jeff Holz for the Continental information.

The third article addresses the question from C. Rennie Waugh, 5705 Goleta Road, Goleta, C A 93117: ' We have an Associated 2 HP engine, s/n 344256 and are trying to determine when it was built. No one out here seems to know.'

SERIAL NUMBER LIST-ASSOCIATED &. UNITED
                         4 & 5 Digit S/N
Legend: A=Associated Engine, U=United Engine
  -=information not available  

Serial #

Make

Year

HP

1121*

A

1911

2?

*Early Hired Man with unusual ID plate patented Jan. 3, 1911.

20447

A

1914

?

23313

A

1914

1?

23584

A

1914-15

1?

23782

U

1915

-

25325

A

1915

?

30217

A

1915

1?

32860

A

1916

1?

37030

U

1917

__

37289

A

1917

?

52079

U

1916

1?

58125

U

1917

3?

80886

U

1915

1?

81502

U

1912

1?

81790

U

1915-16

1?

83291

A

1917

2

For the last three years I have been conducting a serial number and date search on the Associated-United engines, built in Iowa. This is being done through ads in GEM, letters and post cards sent in the mails, and by going to local shows and recording the needed information directly from the owners. I have found three points of interest in this project. They are:

1) An Associated engine Experimental, with a unique magneto and gear setup (approximately 1915).

2) An Associated engine with a 4 digit serial number (1911).

3) An Associated engine with a 7 digit serial number (1909).(This engine appears to be one made at the start of Associated production. There is no mistake on the serial numbers, as I got the information directly off the engines myself.)

If anyone has any more serial numbers or odd information on the Associated-United Engines, please contact me so I can update the list.

On a general note it can be said that an engine with a 5 digit serial number was built before 1918, and the 6 digit engines appear not to have been built before 1914, as of my present information. This list does not cover the Colt Series engines.

SERIAL NUMBER LIST-ASSOCIATED & UNITED
            6 & 7 Digit S/N
Legend: A=Associated Engine, U=United Engine
=information Not Available TG=Throttle Governed

Serial #

Make

Year

HP

103079

U

1913-14

1?

113445

A

1914

1?

117848

U

1914

2

117925

A

1914

2?

131067

A

1915

2?

133166

A

1917

2?

135873

A

1917

2?

137213

A

1916

2?

143575

A

1916

1?

144744

A

1917

2

151328

_

1917

2?

159412

A

1917

2

165017

A

1918

2?

201175*

U

1926

2?

201826*

U

1926

2?

201853*

U

1926

2?

*These engines were located within 2 miles of each
other by different owners in South hamtom, Mass.!

202539TG

U

1926

2?

202672

U

1926

2?

203204

u

1918

2?

203271

u

1918

2?

205184

u

1919

2?

205204

u

1919

2?

206380

A

1920

2?

250388

-

1915

1?

257067

A

1915

1?

257867

A

1915

1?

258596

A

1915

1?

259146

A

1915

1?

312370

A

__

1?

316784

A

__

1?

321047

A

1919

1?

323808

A

1920

1?

328508*

A

1915

1?

*Experimental Mag gear setup from factory  

332585

A

1920

1?

332840

A

1920

1?

334415

A

1920

1?

337007

A

1921

1?

340886

A

__

1?

342370

A

1920

1?

342529

A

1920

2

344256

A

1921

__

357067

A

__

1?

401405 TG

U

__

4?

509829

U

__

3

510547

A

__

3

605685

A

__

6

610760 TG

A

1920-21

6

801088

A

1918

8

3316784*

-

1909

 

*This engine was on display I at a show in upstate New
York (note 7 digit s/n).