Caterpillar 30

By Staff
1 / 5
Right side after restoring.
2 / 5
Left to right: Max Jones, Troy Jones, Cornie and Brian Bambrook.
3 / 5
Yes, it was a junker.
4 / 5
Parts from the Best 30.
5 / 5
Left side showing manifold and air cleaner from Best 30.

1408 N. Van Buren Otturmva, Iowa 52501

My nephew Max Jones, Blakesburg, Iowa, asked me to write a story
about his Caterpillar 30. After researching serial numbers, Cat
books, Nebraska tractor tests and viewing various pictures, I will
try to write this story.

The C. L. Best Gas Traction Engine Company of Elmhurst,
California, was established in 1910. In 1892 the Holt Manufacturing
Company was formed. In 1925 the Holt and Best interests merged to
form the Caterpillar Company. This leads us to believe that left
over Best parts were used in this Cat 30.

The Cat Thirty was made in 1928 with some parts from the Best
Thirty: the cast iron upper track roller holders, the narrow seat,
roller track guard, manifold and air cleaner along with the air
heater and tube radiator. These parts seem to have been left over
from the Best Thirty. There is no identification tag on the
tractor, but the parts described above along with a casting date of
6-17-27 on the bottom of the transmission case, would establish its
date of manufacture as 1928. This tractor was made in California.
About 750 of this model were made.

The Caterpillar built engine has a 
43/4 bore and 61/2
stroke running at 850 RPM. It has a three speed transmission, 1.7
MPH, 2.6 MPH, and 3.6 MPH with a standard of
433/4 inches. The weight of the Cat 30 was
9910 pounds. A number of special equipment items were available,
i.e., grousers, front and rear PTO, double rear PTO, a belt pulley
and others.

The Nebraska Tractor Test is a yardstick for testing horsepower
of tractors. This testing was started in 1920 at the University of
Nebraska. The Best 30, a forerunner of the Cat 30, was tested in
1921. The Cat 30 was not tested until 1936, so this indicates that
this tractor was not tested, although a Best 30 was tested in 1924.
While this tractor is a Cat 30, many of the parts are from the Best

Max works as a welder at the John Deere Works in Ottumwa. Along
with a friend, Cornie Bambrook Jr., a retired welder from John
Deere, he worked many hours restoring the tractor. Brian Bambrook
and Troy Jones helped with the restoring. Max bought the tractor at
Fairfield, Iowa. The tractor came from Kansas and was thought to
have been used by a county.

The idlers and sprockets were wrapped with rags and bound with
wire to keep the sand out. The motor was supposed to be running,
but it had to be pushed onto the low-boy. Max claims to have six
Cats, but I think it is more correct to say about ‘four and
forty three hundreds.’ These parts tractors are about the only
source of parts.

Max and Junior disassembled the tractor, replaced broken or bent
parts including new rings, had valves ground and shimmed the
bearings, rebuilt the idlers including the shafts. One of the track
rails had to be replaced and one drive sprocket rebuilt, and they
replaced the drawbar. One link was taken out of each track rail,
making a 30 link rail instead of the standard 31 link rail. A new
seat was fabricated by Jerry Gast of Wapello, Iowa. The machine
work was done by Chester Gillen Jr. Machine Shop in Blakesburg,

The cylinders were cracked and had to be welded. It appeared
something had fallen on the platform, bending the clutch and
steering levers. This made it necessary to make some new parts and
straighten the levers. A little over fifty pounds of #6013 welding
rod was used and this was by these two experienced welders. After
all the repair work and the cleaning, it was given a few coats of
paint. It took about $50.00 of primer and $200.00 worth of grey
paint to make it look like a new tractor.

As Max or his twelve year old son Troy will drive this Cat
Thirty in the parade at Midwest Old Threshers at Mt. Pleasant,
Iowa, September 2-6, 1993, Troy claims this Cat 30 is his tractor.
I am sure it will be their pride and joy. It came from a basket
case to a bright and shining tractor with its new grey paint.

Max is restoring a C. L. Best 30 with serial number#l 97, that
has a two speed transmission. He hopes to have it ready for the
1994 Midwest Old Threshers.

Information was taken from C. H. Wendel’s books: American
Farm Tractors and Nebraska Tractor Tests.

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