An an entirely new design from International Harvester, the 400 series was based around a modular concept of construction and consisted of four machines – a single-engined open bowl scraper (the 431), a twin engined open bowl scraper, subject of this article (the 433), a single-engined elevating scraper (the 442) and a twin-engined elevating scraper (the 444). By Richard Campbell
All shared a common tractor unit and a great deal of other components that allowed International to rationalise production and reduce its parts inventory considerably.
The modular concept for motor scrapers was not solely International’s domain as Allis-Chalmers had already introduced its ‘200 series’ (260B, 261B, 262B and 263B), again all sharing a common tractor unit and many other features.
Introduced in 1972, the 400 series expanded International-Harvester’s range of motor scrapers that up until that time was limited, and all of which were decidedly old technology.
International aimed squarely at the fattest segment of the motor scraper market – 14 to 20 cubic yards – an area long dominated by Terex & Caterpillar.
Traditional International owners were keen buyers of the new machines but International Harvester had a bit of an uphill task convincing buyers of other brands. As a result, sales of all the 400 series machines were moderate despite their efficiency, reliability and good looks.
Unlike other manufacturers of the period, International did not offer any form of ride suspension on its motor scrapers, and that may have been one of the limiting factors in their acceptability.
An uprated 433B was introduced in 1977 featuring an increase in horsepower in the tractor unit from 310 to 326 plus a higher capacity hydraulic pump and a few styling changes. Noticeably this included the relocation of the front headlights from being inset into the bumper to the upper sides of the radiator surround.
Following the Dresser buy-out of International Harvester’s Payline division in November 1982, the remaining 400 series machines (433B & 444B) were dropped from the product range. The 431B and 442B had been put out to pasture a little earlier after a very short production run.
This left the little 11 cubic yard 412B elevating scraper as the sole survivor of a once proud range of International Pay Scrapers.
The International 433 Described
International used two of its own design engines to power the 433.
In the tractor unit was the 310 horsepower DVT800, a turbocharged, intercooled V8 diesel and in the scraper, a 185 horsepower DT466, 6-cylinder turbocharged inline diesel.
Both engines were used in other International machines increasing parts commonality between units.
Twin-Disc supplied the matching 5-speed powershift transmissions.
On a smooth haul road the 433 was capable of 34 mph.
Shoe-type brakes were fitted to all wheels and these were air activated.
The gooseneck of the 433 was similar in design to that of the Terex TS-18 but the steering system was decidedly Caterpillar in origin, having two “V” shaped multiplier links connected to the steering cylinders which were mounted high up on the neck.
Even the apron actuating system was similar to Caterpillar’s featuring inside mounted apron arms with lever and link to raise and lower.
Compared to previous International scrapers, the 400 series machines looked quite angular in appearance with most of the body panels being flat or squared off.
This cut down the cost of manufacturing considerably with very few compound curves to worry about.
The bowl held 14 cubic yards struck and 21 cubic yards heaped and was equipped with 4-section reversible and interchangeable cutting edges.
Two vertically mounted double-acting hydraulic cylinders attached directly from the top of the gooseneck to the bowl spreader bar to provide lift and cutting edge penetration.
These produced some 28 tons of down force.
Ejection was bulldozer style, powered by two double-acting hydraulic cylinders.
A bowl spill-guard was fitted as standard equipment and helped prevent spillage of large chunks of earth or ‘tombstones’ falling over the back of the bowl onto the rear engine enclosure and fuel tank.
Compared to some of International’s previous scraper offerings, the 433 had very good visibility all round, even the exhaust stack and aircleaner inlet being set back to allow the operator a better uninterrupted view to the right.
An instrument panel was set to the right of the steering column and contained all the necessary gauges and also included a tachometer. A smaller panel containing the rear engine’s gauges was set inside the rear left hand side cowl of the scraper unit.
The 433 was usually delivered with a Bostrom air suspension seat and an open, non-ROPS cab with windshield wiper as standard equipment.
A full ROPS air-conditioned cab was available as an option for colder climates.
The 433s could also be supplied with International’s “Pay Mate” dual loading system. This allowed two 433s to load each other without the use of a separate push tractor similar to Caterpillar’s “Push-Pull” and Terex’s “Twin-Hitch” systems.
Pay Mate was factory installed and could not be retrofitted to existing machines as reinforcement was required to the machine’s frame. At the rear the scraper’s push block, which contained the Pay Mate hook, was extended and a substantial radiator guard for the rear engine was installed.
The New Zealand Connection
As far as the author is aware there were only two 433 scrapers imported by International-Harvester New Zealand.
Both were delivered new to John McLaughlin Ltd, an established IH user who already had some IH E211 elevating scrapers in his spread.
The 433s appear to have changed hands a couple of times subsequently and it is not known if they are still operational or even in New Zealand.
Can any of our readers fill in the blanks?
For the Diecast Model Collector
Only one model of International’s 433 has been produced.
This is to 1:25th scale and manufactured by First Gear.
It is of exceptionally good quality, very accurate and fully functional with very little missing from the model other than oil leaks and an operator!
The model has been issued with a couple of variations since its first release in 2004 – a limited run ‘mining white’ version, a gold plated example, and as a very rare matched pair equipped with IH’s Pay Mate dual machine loading system.
An impressive model worth adding to any large scale collection.
Brief Specifications – International 433 PayScraper
Engine (front): International DVT-800, V-8, turbocharged and aftercooled diesel rated at 310 flywheel horsepower @ 2600 rpm
Engine (rear): International DT-466 six-cylinder, inline, turbocharged diesel rated at 185 flywheel horsepower @ 2500 rpm
Transmissions: Matched Twin-Disc 5-speed powershift countershaft type transmissions
Top Speed: 34 mph
Brakes: Full air operated expanding wedge type on all wheels
Steering: Two cylinder hydraulic with multiplier linkage. 90° each way
Turning Circle: 34’
Capacity: 14 cubic yards struck, 21 cubic yards heaped
Operation: All hydraulic
Length: 41’ 5” (without Pay Mate attachment)
Width: 11’ 10”
Height: 12’ 2”
Operating Weight: 34 tons (empty), 59 tons (loaded)