SAMSON GAS ENGINES

By Staff
Published on June 1, 1997
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Figure 1.
Figure 1.
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Figure 8.
Figure 8.
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Figure 9. Samson letterhead.
Figure 9. Samson letterhead.
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Figure 11. Samson engine guarantee.
Figure 11. Samson engine guarantee.
5 / 18
Figure 12.
Figure 12.
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Figure 10.
Figure 10.
7 / 18
Figure 13.
Figure 13.
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Figure 14.
Figure 14.
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Figure 15.
Figure 15.
10 / 18
Figure 16.
Figure 16.
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Fig. 336.-Outside view of generator.
Fig. 336.-Outside view of generator.
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Figure 2.
Figure 2.
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Figure 3.
Figure 3.
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Figure 4.
Figure 4.
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Figure 5.
Figure 5.
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Figure 7.
Figure 7.
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Figure 6.
Figure 6.
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Figure 17.
Figure 17.

2440 Thomas Street Ceres, California 95307

John Minor Kroyer began Samson Iron Works with a centrifugal
pump of his own manufacture and gas engines soon followed. The
first Ironworks was located on the corner of California and
Washington Streets in Stockton, California. From this small
beginning it soon became the largest manufacturer of engines and
pumps on the Pacific Coast.

In my great desire to learn more about Samson Iron Works I have
come to realize the great changes that occurred in this last
century. There was a time in this country when big corporations
hadn’t yet forced the small competitor out of the market. This
was a time when a good idea and hard work made a difference in the
lives of the people.

This was a time when a ‘grass roots’ gas engine
industrial explosion took place. Hundreds of manufacturers began
mechanizing the farm and bringing a better standard of living with
it.

In the early days of Stockton, John settled here to pursue his
dream. He saw an increasing need for new equipment and a changing
agricultural picture involving the area’s conversion from grain
to more diversified farming. He settled in a fertile land near the
famous delta where marshland was too soft, too wet, for too
long.

Three million years ago, virtually all the Sierra Nevada
Mountains above three thousand feet were covered by sheets of ice.
These glaciers ground the mountains away and as the ice melted, the
rivers carried away the alluvial sediment down to fill the
‘great valley trough’ in some cases as deep as two hundred
feet.

As geologic forces raised the north and south ends of the great
valley, the San Joaquin and Sacramento Rivers took the runoff
waters to the sea via the Carquinez Strait and San Francisco Bay.
Where the rivers met, they came under the influence of the Pacific
tides that flowed in through the Strait. This slowed the flow of
both rivers and a huge delta marsh developed in the valley west and
northwest of what someday would be known as Stockton. As California
grew, this rich and fertile delta land drew men who, in due course
of time, would alter dramatically the face of California’s
agricultural economy. The control of this environment has always
been a challenge to men who dream. Anywhere near this delta, winter
floods were an annual event. Long and rainless summers parched the
land. It was a wonderful market for power and pumps and quite early
stimulated the development of local industry. Men dreamed to
reclaim this delta land and to grow the proverbial cornucopia on
its fertile face. But how?

This was the magical time when John Kroyer began building his
‘open vaned’ centrifugal pumps-pumps designed to move
gravel and sand and do it efficiently. The history of California is
the movement of water. Samson pumps played a significant role in
the development of the state and its agriculture. These pumps were
built from thirty gallons a minute to ninety thousand gallons per
minute. Special sizes and applications could be custom ordered. In
all cases, their construction was heavy and substantial, being
built for irrigation, reclamation and domestic work. All of the
pumps were available in a brass version and prices were available
on application to the company. (Fig. 1.)

Many of the old photographs depicting pump and engine
combinations show the engine at ground level while the pump itself
sits below ground level in a ‘pit,’ sometimes quite deep.
Of course these were belt-driven applications. It must have been
very inconvenient to service pump glands to say the least.

Samson Engines

John built engines to operate his pumps. He built many sizes and
types but his first engines were farm engines such as we collect
today. John was very interested in using distillate and other low
grade oils for fuel. These fuels were cheaper than gasoline and his
idea was a ‘generator’ that used heat from the engine to
vaporize fuel oil. This generator (Fig.2) consists of a chamber of
two compartments separated diagonally by a partition on which
projects a series of ‘ribs.’ The oil takes a zig-zag course
down the surface heated by the exhaust through the chamber beneath.
The oil is fed at the top. The vapor is drawn to the engine through
the pipe and small chamber around the exhaust pipe as shown. A
three-way cock regulates the quantity of the exhaust required for
evaporative effect in the generator. The cold engine is first
started on gasoline which is supplied to the intake manifold via a
suitable carburetor. When the generator is warmed up, the oil is
turned on, and the governor then regulates the fuel charge, these,
of course, being throttle governed engines.

The crude oil referred to is also known as bunker oil. One
testimonial letter from a Marysville, California, man states:
‘We are successfully using Coalinga crude oil, as it comes from
the ground, for fuel.’ (October 18, 1904) John didn’t build
these generators for long. They were expensive and took up as much
room as the engines. All the early engines I’ve seen are
equipped in some way or another to run on distillate, and it
wasn’t until the very end of engine production that a
‘gasoline only’ model was produced.

John Kroyer’s earliest engines were beautifully built by men
skilled in the art of foundry and machine work. Vertical fly ball
governors, fuel preheaters and ‘wipe ignition’ characterize
these models. The earliest engines had a ‘cloverleaf’ cross
section of flywheel spoke as opposed to an oval section. These are
known as cloverleaf Samsons among collectors. One in our area is a
15 horsepower model serial #122. It has an unusual nameplate of
cast iron stating it was built in March 1902. Its rated speed is
260 rpm (See Fig. 3).

Most of these early engines had an ‘N’ preceding the
serial number stamped on the brass builder’s plate. Of course
these are known as the ‘N’ model. This was the engine that
firmly established Samson Iron Works as a reputable engine builder.
All ‘N’ models above three HP have vertical fly ball
governors. I have seen two 3 HP ‘N’ engines, both built
with a horizontal governor with unusual ‘tear shaped’ fly
balls. This leads me to believe that 3 HP engines and smaller
engines use the horizontal version of the governor. However this is
pure assumption on my part, as I have never seen a 2 HP ‘N’
engine. Does anyone out there know of one?

It is not known if serial #122 described above is an
‘N,’ its serial number being void of the ‘N’ stamp.
However in all respects it could be an ‘N,’ as it is
identical in all features to other ‘N’ engines.

I know of these ‘N’ engines:

HP

Ser#

RPM

Date

Gov’nor

12

N1455

Vert.

6

N1484

Vert.

4

N1571

Vert.

4

N1624

300R

Vert.

6

N1913

1906

Vert.

4

N1943

Vert.

3

N1955

350R

Horz.

3

N1783

350R

Horz.

I would be very pleased to add any additional serial numbers to
this list.

There are a number of variations on these ‘N’ engines,
and it’s often said that every engine is different. But an
in-depth study of engine design reveals a very interesting natural
progression of mechanical improvements. This is why Samson engines
fascinate so many people. John Kroyer was a prolific inventor and
mechanical genius. The study of Samson engines thus becomes a study
of John M. Kroyer and his way of thinking. These engines reveal a
genius seldom seen in the early days of mechanizing
agriculture.

These ‘N’ engines used a float type carburetor with the
fuel mixing in the main air stream created in the intake manifold.
The combustible mixture was then throttled by the governor valve.
An eccentric driven off the cam gear operated the wipe ignition
system and the same cam gear opened the exhaust valve via a unique
rocking lever arrangement. The intake and exhaust chamber were cast
as one unit so as to utilize the heat of exhaust to further
vaporize the incoming fuel charge.

The early ‘N’ engines used a two piece wipe ignition
system composed of an insulated stationary electrode situated in
the precombustion chamber along with a movable electrode which
screwed into a threaded opening in such a way as to allow the make
and break to occur. Later ‘N’ engines used a flange mount
which contained both the stationary and movable electrodes. This
was an improvement over the old system, being much easier to adjust
and service the ignition system. In both cases the precombustion
chamber held the working parts of the ignition system.

The ‘N’ model ended production about 1907, which
coincides perfectly with the erection of a new brass foundry one
hundred feet by one hundred twenty-five feet long. It was a modern
fireproof structure and it marked the beginning of a new series of
engines which bear a remarkable resemblance to the old style 3 HP
‘N’. (See Fig. 4)

In 1908 another foundry was added which produced crucible steel
castings of the highest grade. Samson Iron Works welcomed custom
work of all sizes and were turning out the highest grade of cast
iron, crucible steel and brass castings. This was the first
facility of its kind in California.

The transition from the ‘N’ engines to the new improved
model falls somewhere between serial No. N1955 and serial No. 2409
which is a late style distillate model. Some call this new model an
‘M’ engine. Some call it the late style engine. Samson Iron
Works calls it their new improved model in their stationary engine
bulletin. These are by far the most common Samson engines seen by
collectors. They are the very best of John Kroyer design, rugged
and strong, built to last. Their reputation lives to this day,
remembered fondly by those who knew them firsthand.

Serial No. 2409 is a 4 HP model with a very unusual transitional
‘hammer break’ ignitor. It is different from the standard
ignitor seen on these models. Note the float type carburetor and
fuel preheated used on this engine. (Fig. 5)

The highest serial number I’ve seen on any Samson engine is
No. 6106, a 12 HP model. This is a straight gasoline model with no
provision for distillate vaporization. It has the late style carb
and intake manifold. These engines are characterized by a heavy
cast iron crank guard which carried an oiler that lubricated the
connecting rod via a ‘wipe cup.’ These were the last series
of engines produced by Samson and are the most common. No
presenters and a carburetor change is the basic difference from the
new, improved distillate model. (Fig. 6)

Engines 3 HP and below use a cast ‘I beam’ construction,
while larger .engines use a magnificently turned rod with heavy
brasses fitted. I own two Samson’s and had a third, and each
one had a freeze crack in the same place. This is under the head
and cylinder near the head. This must be the weakest area in the
Samson design.

The serial number break for the new style distillate and
gasoline models is between serial No. 3428 and serial No. 4011, No.
3428 being a distillate engine, while No. 4011 is a gasoline
engine. See serial number list for the new, improved model.

SERIAL NUMBER LIST FOR

NEW, IMPROVED MODEL.

HP

Ser. No.

Type

4

2409

Dist.

2

3070

Dist.

3

3103

Dist.

3

3263

Dist.

6

3428

Dist.

3

4011

Gasoline

3

4367

3

4465

5

4831

2

4911

5

5067

6

5106

8

5148

4

5187

3

5711

12

6106

I would be pleased to add additional serial numbers to my list.
Samson Iron Works also built a series of vertical engines which are
covered in my article ‘Legacy In Iron; Samson Engines’ (GEM
February 1996). Here is a serial number list for these engines:

SERIAL NUMBER LIST FOR

VERTICAL ENGINES

HP

Serial No.

2.5

110

2.5

325

2.5

944

2.5

2270

It is not known if Samson produced only the two and a half
horsepower vertical. Rumors indicate they may have been built in
other horse powers. Please contact me if you have any vertical,
especially larger than 2.5 HP.

I have seen many engines and pump installation photographs in
which the cooling system was simply a ‘bleed’ off the
discharge pipe with a cock inline to control flow. In other cases,
such as the portable wood sawing outfit, a large tank was used
along with a small centrifugal pump to circulate the water. Fuel
tanks were often comprised of a simple stand made of wood on which
the main distillate tank and a smaller tank for gasoline were
mounted and connected by suitable lines. The tanks were mounted
high enough so the fuel would flow to the carburetor by
gravity.

Most of the Samson distillate engines use a float type
carburetor which had a small brass type pipe protruding from the
top of the float chamber. A fuel shutoff valve was also mounted on
the distillate line so distillate flow could be shut off to the
carburetor. This was essential because the carburetor had to be
empty of fuel oil before it could be started on gasoline. To start
a cold distillate engine, gasoline was pumped into the small brass
pipe with an oil can until the carburetor was full. Of course, the
distillate supply was shut off. The engine was then started on
gasoline, and when the engine became warm enough to vaporize the
fuel oil, the distillate valve was opened and the oil metered
through the needle valve in the carburetor. If more gasoline was
needed, it was simply added to the carburetor until the correct
temperature was reached. There was no other way to get the gasoline
into the carburetor. Some of the very early engines that utilized
Kroyer’s ‘fuel oil vaporizer’ used an unusual
carburetor. It seems to have had two fuel lines, one distillate and
one gasoline. Further research will hopefully reveal more detailed
information on this system. (See Fig. 17)

I have the original skids for the late style 5 HP Samson, serial
No. 4831. This is simply an undressed fir plank measuring three
inches by twelve inches, about five feet long. It is still in fair
shape after all these years, excepting some minor wood rot on the
ends.

Samson Iron Works built odd engines of which very little is
known. A surviving oddity is a small vertical engine with a single
flywheel and a pushrod to activate the exhaust valve. It has a
mixer valve for fuel and appears to be a competitive version of
their engine designed to compete with the hordes of gas engines
then on the market. All other vertical Samson engines I’ve seen
use a vertical side shaft to activate the valve and igniter.

I’ve seen a 5 HP ‘N’ that was never drilled for a
plate. A serial number can’t be found, and one wonders why,
be-cause Samson engines invariably carried a builder’s
plate.

There is a large Samson horizontal engine in a side shaft
version, about 25 HP. Its builder’s plate indicates it was
built at the old address, making it a very early engine. It uses a
bevel and spur gear drive to drive the side shaft and a ‘hand
hole’ is provided in the frame work to grease the gears! It is
the only horizontal side shaft Samson engine known. It is quite
different from the ‘N’ engines, although it possesses
certain features which are pure Samson, notably the fly ball
governor and ignition system. It is also a distillate engine, but
it uses a Lunkenheimer mixer with a gasoline needle and a
distillate needle. It also possesses an air preheated designed to
help vaporization of fuel. This engine spent its working life
pumping water. Not much more is known of its history. (See Fig.
7)

As Samson Iron Works grew, so did its sales territory. It
wasn’t long before they had established offices in San
Francisco, Los Angeles, and Fresno, California. They had many
dealers around the state and ‘agents’ who acted as salesmen
and technical advisers, who set up plants and provided instruction
of operation. I’ve seen several letterheads from these agents
and they are very interesting, showing Samson engines, pumps and
other products.

Samson Iron Works sold a complete line of oil and greases,
belting and pipe fittings. They sold Samson pump jacks and complete
pumping plants. They sold Samson oil tractors and marine engines,
including a very extensive line of propellers and bronze stern
bearings, and packing boxes. The Samson marine catalog exists and
depicts a very complete line of Samson engines, well designed and
sturdy. However, none of these engines are known to exist. They
were made from four to one hundred and fifty horsepower. These
engines used Schebler carburetors up to fifty horsepower, and
larger engines used the Samson improved, float-feed carburetors.
These wereignitor engines designed to run on distillate fuel. They
were built with one, two or three cylinders. (Fig.8)

In their first year of operation Samson employed twenty men. In
the second year, thirty men and in the third year, forty. In their
prime years they employed up to two hundred men representing all
trades. They were one of the most successful and thriving
manufacturing facilities in Stockton. It must also be remembered
that a very extensive line of agricultural tractors were also built
in the plant.

The title for this article comes from a small advertising piece
owned by a friend. It features a small, round card about two inches
in diameter, depicting a Samson engine with the slogan: ‘Samson
Gas Engines. First In Heart, First In Peace, First In The Eyes Of
The Purchaser.’ It is red on a white background. Around the
outer edge it says, ‘Samson Iron Works, Stockton,
California.’

In Fig. 9, a letterhead from Samson Iron Works is illustrated.
It is dated March 27, 1911 and is signed by H. L. Marsh who was the
sales manager.

In Fig. 10 , we see John M. Kroyer in his office at the iron
works, and if the original photograph is studied with a magnifier,
photos of his marine engines can be seen hanging on the wall. The
identity of the woman is not known at this time.

In Fig. 11, we see the guarantee that covered the stationary and
marine engines. Note the corporation stamp dated July 9, 1902.

In Fig. 12, we see the front cover of their marine catalog. It
depicts a red, new, improved model, distillate engine and a
‘marine blue’ marine engine. It’s a beautiful cover,
embossed and highlighted with gold.

Fig. 13 is a 4 HP ‘N,’ serial No. 1571, Fig. 14 is a 5
HP new improved gasoline model, serial No. 5067. In Fig. 15 we see
a very extensive list of Samson engines sold to different
reclamation districts, cities and companies. These are the large
horsepower, vertical, multi-cylinder units which were used mainly
for driving water pumps and electrical generators. These units will
be covered at a later date. Fig. 16 shows the signatures of J. M.
Kroyer. The top one is from approximately 1910, and the bottom one
from approximately 1940. Both are bold and strong.

There are a number of pieces of Samson literature available. The
Samson stationary engine catalog exists for the new, improved model
as well as a catalog showing their marine engines. There is a
Samson wood-sawing brochure and a pumping plant brochure. There are
several centrifugal pump bulletins and a wonderful little
testimonial booklet. I am sure there are others which I haven’t
seen and, of course, there are several articles written over the
years in GEM focusing on Samson engines.

I wish to make a few additional comments. The earliest Samson
engine recorded on paper is from a man who wrote Samson Iron Works
expressing his satisfaction with his Samson engine. It is dated
January 1900, dating the original purchase to at least 1899. Samson
Iron Works originally started in 1898.

The information for this article came from many sources, and
piece by piece it came together. A large number of people shared
their information and made copies of what they had. To these folks
we owe a big thanks, for without them this story couldn’t have
been written. Only one person refused to share his Samson serial
number, and in every other case, folks went out of their way to
help and encourage. It’s this kind of people who make this
hobby wonderful and filled with fun.

I am always searching for more Samson engines and parts. I need
the intake manifold and governor for a late style 5 HP gasoline
model. I am interested in anything that concerns these fascinating
engines and their maker. I am glad to correspond with anyone with
Samson interests.

You see, the story is never ending, our search never over. This
is what creates such an interesting and satisfying hobby. It
challenges our senses and fills our need to preserve and protect
that which is near to our hearts.

Very little is actually known of the man who spent his life
making life easier for others. John M. Kroyer cast in steel what
others put on canvas, but his work gave us all a better life, a
higher standard of living. It is too bad the genius and personality
of Mr. Kroyer hasn’t been chronicled in a more personal way.
John M. Kroyer was a remarkable man who possessed a genius and
ability which has gone unrecognized in history. At a later date I
will write about the man, his failures and successes. John died in
August 1945, in St. Joseph’s Hospital in Stockton, the city he
loved so well. He lies buried in a Lodi Cemetery under a simple
marker, with no mention of his great contribution to his fellow
men.  How quickly in our fast and furious world a man and his
work is forgotten! It is with deep respect to him these words are
written. We cannot overemphasize his contribution to agriculture in
the form of reclaiming the wonderful fertile delta land and the
irrigation of dry ‘desert like’ land which water turned
into a paradise.

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