TRACTOR TALK

LAST SCREAM OF THE JIMMY

In 1954, when Oliver needed a powerful diesel to one-up their competitors, they went to General Motors. The Detroit Diesel Division built some of the most lightweight and compact, yet very powerful, diesels on the market at the time and more than a few tractor manufacturers went that route in the years between 1950 and 1970. The 1954 Super 99 GM was powered by a General Motors 3-71 and made 80 horsepower on the PTO. That was BIG power for ‘54. The Super 99 GM lasted through 1958 as a step above the 65 PTO horsepower Super 99 Diesel powered by the familiar Waukesha-built, Lanova cell six-cylinder.

GM power continued through the evolution of the Oliver tractor line in the ‘50s as the high-power alternative over the Waukesha engines. The ‘59-61 990 and 995 GM both were Jimmy-powered, again with the 3-71. Power was up a little and those tractors were restyled and improved but the big news came for 1960, when the 1900 debuted. It featured many improvements, not the least of which was the update to the recently introduced 4-53 four-cylinder Jimmy. It was almost exactly the same displacement as the 3-71 (213 ci vs 212), having more, but smaller displacement cylinders.

For 1965, the Oliver 1900 was revised into the 1950. It’s counterpart was the 1850, which was essentially the same tractor powered by a six cylinder... either a Waukesha gas or propane, or a Perkins 354 (93 PTO hp). This was the era when

Oliver certified the power on their tractors. Essentially, Oliver promised their tractor would deliver no less than their certified power. Each tractor was dyno tested to produce at least the minimum advertised power. If they didn’t, they were tweaked or repaired until they did. Oliver had been doing that for a long while but starting with the 50 series, they advertised the fact and applied a decal that showed the actual power reading and the signature of the dyno tech. Not coincidentally, those numbers closely matched the Nebraska ratings. All this inspired a fair bit of trust.

The 1950 series was offered in five variations, a fixed tread standard/ wheatland, a riceland, two versions of a rowcrop (narrow or adjustable wide front) and a four-wheel drive. There was also a commercial version that came in yellow, so it could be called a sixth variant. The 4-53 had been tweaked by this time to produce 105 PTO ponies and as a result, Oliver could brag that it had the most powerful rowcrop tractor on the market. Of course, Oliver faced the same limitation as everyone in that era.. putting that power to the ground. Tire technology was advancing but at this time, being able to use 100 horses on a rear drive only tractor could be problematic. That’s where the four-wheel drive tractors came in.

The 1950 used essentially the same front driving axle technology as had the 1900, namely a Clark axle and a take-off from the transmission to power it. The front axle ring and pinion ratio and tire size was carefully matched to provide even pull, so that limited tire size choices to only a few, one being super wide Goodyear Terra Tires.

The tractor could be operated for long periods with the front axle engaged, or in rear drive only. The 1900 and 1950 heralded the high-power, non-articulated tractors that have come to dominate the market these days. Oliver also debuted a Levy hydraulic front drive axle option in this era for use in times when only occasional traction help was needed. They hydraulic pump was driven of the front of the engine and a pair of hydraulic motors drove the front wheels. It worked well but was expensive and didn’t sell well.

If a farmer needed more traction, the

mechanical system wasn’t much more expensive than the Levy.

Interestingly, the 1950 rear drive and four-wheel drive tractors were tested at Nebraska at the same time. Both achieved exactly the same 105 horsepower at 2400 rpm PTO rating. For drawbar horsepower, they actually weren’t far apart, the reardrive making a 92 horse rating with no ballast and the 4x4 at 96. With maximum ballast, the rear drive actually was higher than the 4x4 at 98 horses versus 93 but the 4x4 had less wheel slip. When you look at drawbar pull, you see the 4x4 pull ahead, delivering 17,575 pound @ 14.6 percent slip versus 12,880 pounds @ 14.73 percent. The Nebraska tests are done on a traction pad and don’t factor in low traction issues. Give the two rigs some soft ground to play in, you only get one guess who would win the contest.

The 1950 was in production for three model years, to the tune of 36,450 units. This included all configurations and we didn’t see a breakdown of how many four-wheel drive units were built. They are relatively common today, so they must have sold reasonably well. Overall, more than 36K could be called a good run, proving the 1950 was popular. It was replaced for ‘68 by the 1950-T, which was essentially the same tractor but powered by a turbocharged Waukesha six cylinder that was certified for exactly the same power as the 4-53. The two versions coexisted for a short while. It unclear exactly why the GM engine was dropped but it probably came down to dollars and cents. The Waukesha was certainly quieter!

Noah Wheeler’s 1966 1950 has an interesting history. It was completed June 14, 1966, equipped more or less as a ricefield tractor. One of the main differences in a Rice tractor is the tires, in this case the deep-tread R2 tires, which are suited to deep mud. This also requires rear fender extensions, which were ordered. The build card, available from the Floyd County Historical Society (www.floydcountymuseum.org) has a few unusual options that we cannot decode, such as for the hitch and the hydraulics. On June 22, 1966, the tractor was shipped to the Richmond, Virginia, Oliver dealer and from there the trail goes cold until 2018, when Wheeler bought the tractor in very rough shape from a Michigan seller.

The IH 550 5-bottom plow isn’t a great deal of work for the 1950, even the tough ground at the 2020 Alvordton Plowing Days. Wheeler dug into the Oliver as soon as he got it in 2018. It had a scabbed on cab, quickly removed, some tin was replaced and the tractor given a barn quality paint job. Noah loves Detroits, so he reveled in doing an upper end overhaul on the 4-53. Since then, the tractor has taken a place in farming 220 acres, mostly kept in wheat and soybeans.

The operator station was on par with the era, but Olivers had a nice seat. They came standard with power steering and a steering wheel that pivoted and telescoped. This tractor was ordered with the Hydra-power drive, which allowed the operator to split THE GEARS ON THE fly. THE BASE models only had the standard 6-SPEED. THERE WERE FINAL drives with high speed gears and some with a creeper gear.

The front axle is from Clark, a type used in Clark loaders, and it’s plenty beefy. It was DRIVE FROM A TAKE-OFF IN THE FINAL DRIVE

The 2-stroke 53 Series diesels appeared in late 1957 as an evolution of the loopscavenged (valveless, inhaling and exhaling via ports) 51 Series that had debuted in the early ‘50s but reverted to the more successful Uniflow system GM had debuted in 1938 (intake ports in liner but exhaust through valves). Like the 71 series, the 53 were modular and came in two, three, and four-cylinder inline configurations, plus some vee configurations as well, including 6V, 8V and even a few 12V engines. The 53 Series became as respected as the legendary 71 Series and lived on to the end of the 2-strokes in the mid-‘90s, when they died from not being emissions-friendly enough. The 1900 models used a first generation 4-53 with a 17:1 compression ratio that made 89 PTO hp (about 100 flywheel). In ’62, with the 1900 B models, and the later 1950, they upgraded to the 4-53N, which had a 21:1 compression ratio, four valves per cylinder and developed 100 PTO hp (about 108 hp flywheel) at the typical 2400 rpm tractor rating. With a 2800 rpm rating, as seen on many on-road or marine units, the 4-53N made 126 net hp at the flywheel. Note the “Certified” decal.