Like most Tractor manufacturers, the Oliver Corporation looked for other venues in which to sell diesel engines. One that kept them pretty close to their agricultural roots were power units. Power units had many uses in industry and agriculture. Primary uses were to run generators, pumps, sawmills, concrete mixers, conveyers, balers, air compressors, hammer mills, hoists, winches… anything that needed power where there was no electricity. They could be adapted to pieces of towed equipment, such as pull-behind combines and to self-powered equipment like surface compactors.
Oliver started producing diesel power units in 1950 and offered them with their full range of engines; gasoline, LPG and diesel. When they debuted, the primary line of Oliver tractors included the 66, 77, 88 and 99 so the power units corresponded by mounting the engines available in those tractors. To designate them, a “1” was added, so the 166 Power Unit had the same engine as the 66 tractor, for example. Rating varied little and there a few tuning tweaks necessary to suit the application. Besides some standardized units, Oliver offered to custom design for specialized applications.
Oliver had teamed up with Waukesha for many years to build their engines, gas or diesel. They all shared a similar architecture. The diesels were of the Lanova type, even though Waukesha did not use that combustion system. Waukesha used a Ricardo IDI chamber on it’s own diesels but since Oliver had the Lanova license, they produced special engines. The lower ends were very much the same between them, though Waukesha offered a few other variations of bore on stroke on the same architecture that Oliver didn’t use. The special engines were badged “Oliver Diesel” but sometimes are referred to as “Oliver-Waukesha.”
Starting in 1954, the Super Series 66, 77, 88 and 99 tractors debuted. The Power units carried the same designations, e.g. Super 166, Super 188, etc. As it related to the engines, the Super designation came with increased power outputs. The power boost came from bore increases, which was across the board, except for the 199. Tuning and sometimes being spun up a few hundred RPM contributed to the increase.
The Super 166 got a 0.19-inch bore increase, going from 129 to 144 cubic inches. With that and spinning it up to 2000 rpm on the continuous ratings, it jumped from 27 to 37 maximum horses, and 24 to 29.8 continuous horsepower. The 177 got the same bore increase and rpm increase, jumping from 194 to 216 cubic inches, and going from 42.5 maximum horses to 49.5 (38 to 41 horsepower continuous). The 188 got a whopping quarter-inch bore increase to go from 231 to 265 cubic inches. Max power jumped from 49 to 60 horses and continuous from 44.5 to 49. The 199-D kept its original 302 cubic inch displacement and max power rating but by bumping it to 2000 rpm, continuous power went up from 56 to 59. The new rating gave all the Super series slightly higher work ratings in whatever venue they were offered.
“OLIVER STARTED PRODUCING DIESEL POWER UNITS IN 1950 AND OFFERED THEM WITH THEIR FULL RANGE OF ENGINES; GASOLINE, LPG AND DIESEL. ”
In 1957, a fifth diesel was added to the power unit lineup, the Super 225. This unit differed in that it used a Hercules DD-339, which was a direct-injected diesel and part of a new line of DI engines from Hercules. Hercules produced a DD series power unit as well and it’s likely the Oliver was a rebadged version. From the few pictures we’ve seen, the tin may have differed between the Hercules and Oliver units.
The Oliver power units were offered through 1960 and then discontinued. The most likely reason for that is Oliver’s tough financial situation and being purchased that year by White Motor Company. White would soon purchase Hercules as well so the power unit part of Oliver’s operation became redundant. White would go on to purchase, and eventually consolidate, Oliver and Cockshutt. White would develop it’s own brand of tractor, face trouble and be folded into what is now AGCO. That’s for another article.
The restored engines shown here were shot at the 2017 Portland Tri-State Antique Engine and Tractor Show. That year they were celebrating Oliver but we weren’t able to find the owner of these superbly restored Oliver power units. Restoring and collecting vintage power units has become a growing hobby in and of itself, but tractor collectors have long added complementary power units to broaden their collections.