In 1998 I obtained my first engine, an open-crank 3 HP Stover
Type W. In an attempt to find some information on this engine, I
wrote a short article for The Old Machinery Magazine here in
Australia. As a result, I found that I had a 1920 Cooper, badged as
a Stover Type W.
This led me to start researching the Cooper Engineering Co. and
the engines they sold. One of the first things I was told was that
Cooper never built an engine. Subsequently, this proved to be
untrue and I had to sort out the facts from the myths that
surrounded the company. As a result of recent research, it now
looks as though Cooper began importing and rebadging Stovers about
1907 or 1908.
From the mid-1920s, the range of Stover engines were: 1-1/2 HP
Type KE, 2 HP Type KA, 3 HP Type KB and KF, 4 HP Type KG, and 6 HP
Type KC. Although these engines were Cooper badged, they still had
the Stover serial number stamped on the plate, as did the earlier
Enclosed Crankcase Engines
From 1929, Cooper started selling the new CT range of enclosed
crankcase, horizontal Stover engines, and this is where the
confusion started. The 1-1/2 HP Type CT-1 was called the Type TA,
the 2 HP Type CT-2 the Type TB, the 3 HP Type CT-3 the Type TC and
the 4 HP Type CT-4 the Type TD.
The serial numbers posed a problem because some engines had
Stover numbers, but other serial numbers did not coincide. The
latter only started to become clear as I gathered more information;
I will deal with this subject later.
About three and a half years ago, I was contacted by William
(Bill) Quirk, who at 89 years of age was still very active and had
a vivid memory of his time as an employee of Cooper. He started
work in Cooper’s Melbourne branch at the age of 15 in 1927, and
only left to join the RAAF (Royal Australian Air Force) in
Bill told me that instead of importing complete engines from the
U.S., Stover supplied partially machined frame and cylinder
castings to the Melbourne branch through the head office in Sydney.
The connecting rods were made of malleable iron, and, along with
the Wico EK trip magnetos, were made in Sydney. Cooper had
companies around Melbourne manufacture various parts for the
engines. The trip mechanism for the magneto was only made locally
if it was in short supply.
At first, cylinder heads came from Stover. But later, they were
cast locally by McMillan’s of Brunswick, along with other castings.
The castings were fettled and some machining was done at Cooper.
Heavy machining was done by Davidson’s of Latrobe Street.
The white metal bearings were cast and machined in-house and
reamed with a special line reamer by Sutton’s, who still makes
twist drills today.
Royal’s Axles of Carlton forged the crankshafts, which were
machined and ground by Davidson’s. C.B. Dawson, makers of pistons,
rings and sleeves, supplied the cast pistons and rings. Bert Craig,
who owned A. Craig Pty. Ltd., machined and ground the cylinders and
pistons to size for each engine.
Stover flywheels had six holes in them, and on sheep shearing
plants, these were covered with a sheet metal disc. This was done
for safety reasons, because if the shearer brought the hand piece
backwards, it could catch in the holes on the flywheel.
Locally-made flywheels were solid, for the reason cited above. Bill
is unsure who cast and machined the flywheels.
The two small holes drilled in the hopper to allow the Cooper
plate to be affixed were done with a hand drill. Bill recalls the
manager was unhappy with the number of small drills that were
broken; this was solved in a very ingenuous way in 1931.
First, you must appreciate that Cooper’s parent company was the
Chicago Flexible Shaft Co. The Sunbeam division of that company
made household products such as the Mixmaster, therefore Cooper
ended up as the Australian agent for Sunbeam products.
The story goes that a Mixmaster came in to Cooper with a noisy
motor, which Cooper replaced. Some bright person came up with the
idea of fitting a small drill chuck to the old Mixmaster motor,
which was then used to drill the holes on the hopper for the Cooper
And a Stewart Little Wonder engine was converted to an air
compressor for use in painting engines. The painting was done by
anyone with nothing to do at the time – the fitters were expected
to be versatile and able to do all sorts of work. There was a large
chimney still in place that had been used for a boiler, and the
natural updraft of the chimney drew the paint fumes from the spray
Engines were built as – and when – the supply of parts allowed.
One fitter could assemble three engines per day; the finished
engines were run on a test bench for two and a half to three hours
to check speed and power. There was no check on fuel
So, how do you identify a Melbourne-produced engine? Bill told
me that “Made in USA” was chiseled off the frame and cylinder
casting. They also have the solid flywheels and the Cooper serial
As to the number of Stovers built in Australia, no company
records exist, so it is hard to be exact. I estimate between 2,500
and 3,000 were made from 1929 to 1950.
The Melbourne branch moved into a larger, two story building in
the center of the city in 1928. The ground floor was office space
and a showroom, and upstairs was the workshop, machine shop and
welding area. Engines and other machinery were lifted from ground
level by a large hydraulic platform on the outside of the
The number of employees during the 1930s did not vary too much.
There were 15 men including the shop foreman and manager, a
salesman and an accountant.
Cooper in the Mid- 1930s
In 1932, a drop in the value of the Australian pound in relation
to the U.S. dollar made it unprofitable to sell machinery imported
from the Chicago factory. It was then decided to establish an
Australian plant to manufacture the then-existing products that had
previously been made in the Chicago plant.
The new plant in the Sydney suburb of Waterloo came into
operation in April 1933. It is interesting that the production of
Stover engines was never moved to the main factory in Sydney.
Between 1933 and 1935, the number of employees in the Sydney
factory more than doubled. This was at the time of a worldwide
depression, and the Cooper Engineering Co. was one of the few
Australian companies that continued to expand its workforce.
Thanks to American Stover enthusiast Curt Andree, who has access
to the Stover sales ledgers, I have learned that from 1934 to 1936,
Cooper imported 2 HP Type TBs in batches of 100, plus a few 3 HP
This must have been because Cooper was not able to produce
enough locally made Stovers to satisfy sales. Also in 1934, the
first Cooper-badged, Australian-built, Southern Cross vertical gas/
kerosene engines were sold.
Here’s what I know about the different serial numbers found on
Serial numbers such as no. TB 220440 – This serial number is one
of the Stover-built engines that came to Australia in 1934; a
friend in England now owns this engine.
Serial nos. TB 2646, TB 18224 and TA 14249 – With serial nos.
14249 and 18224, I put a 2 in front of each number, and according
to C.H. Wendel’s Notebook, 214249 is a 1931 model, and 218224 is a
1933. I had Curt Andree check these numbers in the Stover records,
and the following information was found. Note they are listed as TA
and TB, not CT-1 and CT-2, as I would have expected, as they were
sold in the U.S.:
TA 214249 (1-1/2 HP) was sold to Stover Windsted Co.,
Indianapolis, Ind., on Feb. 19, 1931.
TB 218224 (2 HP) was sold to F.E. Myers Bros. Co., Ashland,
Ohio, on Oct. 4, 1933.
With serial no. 2646, if you put a 20 in front, it becomes
202646 (1929). Is this one of the first Melbourne-assembled
engines? What I think happened was, a second frame and cylinder
casting were sent to Melbourne with the first one or two numbers
missing. In this instance, 2646 is stamped on the raised area above
the cylinder head, as well as on the Cooper plate.
Serial nos. TB 3701 to 373844 – Some of these engines have
casting dates on their frame and cylinder. These dates are from
late 1936 to early 1938. TB 3701 looks to have been produced in
early 1937, hence 37 was used at the beginning of the serial
number. I think engines with serial numbers beginning with 37 were
produced in the years 1937 to 1942.
Cooper post-1943 serial numbers – The serial numbers were
changed again in 1943, and this type of serial number was also used
on the little air-cooled Type JM, RV and PT engines. So serial no.
TB 461574 is broken down into three parts: 1) TB is the engine
type, 2) 46 is the year of manufacture (1946), and 3) this is
engine number 1574 of that year.
The engine numbers started at 0001 at the beginning of each
year. I own serial no. PT 550001 – engine no. 1 of 1955.
From 1942, Cooper started building the Johnson Iron Horse engine
and Chore Horse generator sets at their new Mascot factory in
Sydney. Serial no. 373844 is a 1942 Type JM (Johnson X400 series
engine). The first of these engines used the 37 series numbers. A
generator set has now come to light with serial no. RVE 442106
(1944), another interesting story.
The 2 HP Type TB was still advertised in the 1950 McPherson
catalog, driving one of their Ajax pumps. I have recently acquired
a picture of a Cooper shearing plant seen at an auction; the engine
is the 2 HP Type TB.
The plate is hard to read, but the serial number looks to be TB
50277, so this could be one of the last Stovers built, eight years
after the plant closed. I am trying to get confirmation that this
serial number is correct.
After the war, Bill Quirk worked for Bert Craig, whose company
machined the bores and pistons for Cooper. He states the last one
he remembers doing was in 1948, six years after Stover closed.
Stover CT Series Engines
There is one last twist to this story that American readers may
be able to answer for me. Bill said that some 6 HP
enclosed-crankcase engines (imported) were sold, confirming that in
1931 these were the 6 HP Type KC. C.H. Wendel says in American Gas
Engines Since 1872, the K series engines “were also available as
special hay press models,” with a cover over the crank and
Bill was adamant that later engines were 6 HP versions of the CT
engines, saying he installed several in the late 1930s. Wendel
makes no mention of CT series engines larger than the 4 HP CT-4. In
the 1937 Power Farming Technical Annual, Cooper is shown as selling
1-1/2, 2, 3, 4 and 6 HP horizontal engines.
Further, a friend obtained some Repair Price List and
Instruction Books for open crank Type K engines. One that was
updated in 1932 shows other Stover products on the back page. There
is a picture of a Type CT engine with the following caption:
“Stover Engines, Completely Enclosed, Automatically Lubricated,
1-1/2 to 15 HP.”
This is the only reference I have found to engines in this
series bigger than a 4 HP. The TD (CT-4) is very rare, so do any of
the larger engines still exist? I would be interested in hearing
from anyone who owns or knows of one of these larger engines.
My thanks to Bill Quirk and Curt Andree for their help with this
Contact engine enthusiast Ron Wiley at: P.O. Box 1011, Victor
Harbor, South Australia 5211; firstname.lastname@example.orgBackground