In 1958, International Harvester heralded a big update of its tractor line with the new, restyled hundred series. While there were major advancements in all areas, this evolution was one step forward and two steps back. Arch-nemesis John Deere was also poised for a makeover and when the new six-cylinder IH tractors began having final drive failures in job lots, “Big Green” was able to knock IH off its top-dog sales pedestal.


Among all the new gear that was introduced in ’58, some of the old workhorses were still available. Among them was the International W-450. This was a legacy member of IH’s fixed-tread tractor lines of the early 1950s that started as the W-6 in 1952, became the W-400 in 1955, and was upgraded to the W-450 in 1957, with more power and a few other improvements. It was heavy and built for tillage in a wheatland-style environment, even though it didn’t set the world on fire with its 49 PTO hp. That weight gave it a little extra grunt over its sibling, the Farmall 450 rowcrop, adjustable-tread tractor. The W-450 was built with gasoline, LPG or diesel powerplants.

Typical of the fixed-tread units, it has a platform and rear entry for the operator. Also typical is a swinging drawbar and PTO. This tractor also has a Torque Amplifier, which spit the gears of the 5-speed transmission. A belt PTO was also ordered for the right side of the tractor (not visible here).

Production of the W-450D started in December of 1956 and continued into April of 1958, with a total of 1,108 units built. It wore the previous generation’s old-style clothes and used the venerable D281 gas-start, four-cylinder diesel. This design had debuted in 1941 with the MD and had served International well. It started life as a 247ci engine (3.87×5.25-inch bore and stroke) then bumped to 263 ci by increasing the bore to 4 inches. A power upgrade came in ’57 by bumping the bore up another 1/8-inch and increasing the displacement to 281 ci. The result was a jump from 55 flywheel hp at 1,800 rpm to 60 hp at 1,800 rpm, and a boost in torque from 188 lb-ft to 201, both at 1,100 rpm. The tractor engines were run at lower rpm than 1,800; in the case of the W-450D, it was rated at 1,450 rpm and produced around 50 flywheel hp at that speed. Torque was about the same between the industrial/stationary engines and the ag units.

This is the diesel side of the UD-281 IH four, a design that was near the end of its run in tractors. When this tractor was built, the basic design had 17 years of service in the IH line, and the bugs were pretty well worked out. It started on gasoline with a tiny, fixed-venturi carburetor, a separate intake manifold, and supplemental combustion chamber. The gas combustion chamber, with spark plugs and a distributor to fire them, was connected to the diesel combustion chamber by a manually opened third valve (called the starting valve) that dropped the compression ratio from 17.45:1 to 6.6:1. The lever that controlled the starting valves also disabled the injection pump or the spark ignition distributor depending on position. When the engine was warmed enough on gas, you pulled the lever and, voila, instant diesel.

The W-450 had a 5-speed transmission and many of them used IH’s new Torque Amplifier (TA). This device allowed clutchless shifting between a high and a low range that split the gears. Most W-450s were ordered with it, certainly the ones intended for farm use. The W-450 used for commercial or industrial use were most commonly seen without it. These tractors also had a standard hydraulic system.

H used its own inline injection pump, which the company classified as single-plunger (four-cylinders) or twin-plunger (six cylinders). The “plunger” designation referred to the high-pressure pump, which supplied pressure to each of the four delivery valves in the distributor block. It featured a fuel pressure gauge so the operator could monitor flow from the filters. It delivered a bit under 70cc and allowed a 1,580rpm high idle speed. The injectors popped at around 750 psi. There were at least three variations of the pump, this being one of the last used on the gas-start diesels. Bosch pumps were also used, many of those going to export markets.

By this time, IH had dropped the McCormick-Deering or McCormick labels. The standard fixed-tread W-450 tractor wore an “International” nameplate, while the rowcrop, adjustable tread (or tricycle) Farmall 450 wore a “Farmall” Badge. The W-450 had a big brother in the 650 model, with a 350ci four-cylinder diesel that made 75 hp at the flywheel and about 63 on the drawbar.

The operator station is a lot more closed in than on a Farmall due to the more substantial fenders and dust shields up front. There’s a plethora of controls on this baby and we can’t tell you what half of them do. You don’t get bored running a W-450! With the spring and shock setup, the seat was relatively comfortable, but the latest tractors had evolved into something better by this time. These seats flipped back so you could stand and drive to avoid the dreaded farmer’s numbutt.
The gas side of the engine shows the tiny carburetor and spark ignition system, driven through the hydraulic pump and run directly off the front of the engine.

The W-450 was one of the last old-style IH tractors built and collector interest is high, especially since so few were built over such a short time.


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