The Mighty "99" Oliver
The Oliver 99 four cylinder tractor was produced from 1938 until 1952. The origin of this tractor began in 1930 when the new Oliver Farm Equipment Co. introduced the 18-27, 18-28 and the 28-44 models of tractors. The 99 has its roots in the 28-44, Oliver's largest tractor of the time.
The history of the 99 engine began in 1930 when Waukasha Motor Co. of Waukesha, Wisconsin introduced their CHS four cylinder engine. Oscar Eggen, Oliver's new Chief Engineer, worked with Fred C. Schulze, Waukesha's Sales Engineer, in a joint effort to restructure this engine for Oliver's usage. A special license agreement was established allowing Oliver complete manufacturing rights to this engine. Casting of parts along with complete engine assembly was done at Charles City, Iowa. Except for carburation and compression ratio changes, this basic engine was used by Oliver in the 28-44, Special and 90-99 tractors until 1952.
During 1934 and 1935 Oliver Engineers along with the Ethyl Corporation of Detroit, Michigan developed a high compression gasoline burning tractor, the Model 70. The 70 was so successful that work was started immediately to develop a high compression cylinder head for the 28-44 tractor. On May 3, 1935 a modified high compression engine was tested a Charles City developing 60 brake horsepower. On August 26, 1936 the Oliver Special High Compression tractor was introduced. This tractor, rated at 32-50 H.P. was sold with starter, lights and a 4-speed transmission. It was offered specifically for high compression usage. The 28-44 also remained in the line for those wanting to use lower grade fuels. The compression ratios were 4 to 1 for the 28-44 and 5 to 1 on the 99.
Sheet metal restyling was takin place for the model 70 tractor and a totally revised model line was being prepared for the 1938 season. The Sreamlined 70 highlighted the 1938 introduction. Model number reconstruction involved the 18-27 becoming the 80. The 18-28 was replaced by the Standard 80. Both low and high compression cylinder heads were offered on these models. The 28-44 received an additional gear speed and was redesignated the Model 90. The Special was then designated the 99.
The 4 3/4 bore x 6 3/4 stroke 443 cubic inch 4-cylinder wet sleeve engine with high compression head was the most powerful unit available in the industry. Replaceable nickel iron sleeves, large inlet and exhaust valves along with a 3" diameter crankshaft proved the engine to be almost indestructible. Force feed lubrication, large cooling capacity and a sensitive variable speed governor were added features. A 14" Borg and Beck clutch assembly easily handled the engines horsepower. The massive transmission and final drive assemblies were engineered by Oscar Eggen to handle twice the horsepower requirement. Easy assess for service was a priority in design along with ball and roller bearing usage. Two gear speed combinations were availale. C33 and C66.
Between 1938 and 1959 few changes occurred in design. In late 1938 at serial number 509561 the Ensign carburetor was replaced by a model TTX-21 Schebler. In 1950 that was replaced by a TSX9394. In 1945 at serial number 12608 the water pump assembly was improved with a carbon disc seal and bypass capability was added. A different drawbar assembly replacing the older 28-44 spring cushioned on was also introduced at this time. The start of the 1949 production saw the release of a new Saginaw steering unit replacing the older Oliver one. However intake valves and springs were released in February 1949.
The introduction of Oliver's Fleetline Series in 1948 was a tremendous success. Charles City's production rates were increased and management decided to move production of the 90 and 99 tractors to South Bend's plant 2 facility in 1959. Several modifications in the tractor resulted after this move.
At serial number 16281 a cylinder head design change was incorporated. Compression ratios were changed from 5.04 to 5.501. At serial number 16841 new fleetline style fenders were designed to accommodate larger tire sizes. A new bull gear cover assembly to provide for the use of the Ride Master seat was designed. Distributor ignition and a new style gear shift lever evolved. Individual 11"x8" double disc steering brakes mounted on the rear axles were also established at serial number 16841.
Having developed the Fleetline series of tractors, Oliver engineers began work on a new 6-cylinder streamlined 99 tractor. A 302 cubic inch Waukesha 6-cylinder dry sleeve engine was incorporated into an extended engine frame and mounted ahead of the older 4-cylinder 99. During the period 1938 to 1952 approximately 9294 90 and 99 tractors were produced.