Classic MachinesScrapers

The Wabco 333 elevating scraper

To date, the largest elevating scraper ever to work in New Zealand, and certainly the most powerful, the Wabco 333FT could trace it’s family tree right back to the original LeTourneau B Tournapull of 1940.   By Richard Campbell

Wabco began experimenting with really large elevating scrapers in 1961 but it wasn’t until 1966 that a twin powered unit was put into production. This was the model BT333F and it certainly raised a few eyebrows with its ability to shift dirt fast, and under conditions which would be considered very marginal for other elevating scrapers.

Continuing development of the type resulted in the B333FT (1969), with the definitive model, the 333FT, appearing in 1970.

With 965 horsepower at its disposal and a rated capacity of 34 cubic yards, the Wabco 333FT had no competition in its size class until Caterpillar brought out its model 639D in 1979, by which time Wabco already had an even larger and more powerful machine, the 353FT, already in production.

Wabco 333FTs were extensively used in surface mining, reclamation and larger general earthworks where their self loading ability was able to cope with most materials and allowed them to work where other types of scrapers would have required a push tractor or two.

Manufactured in the USA at its Toccoa, Georgia production facility, and a token number built at the Rydalmere, Australia plant from US sourced components, total production of the 333FT amounted to approximately 600 machines.

Reliable, comfortable and very popular with operators, the 333FT was replaced by the huge model 353FT in 1978

The Wabco 333FT described

Powered by a 500 horsepower turbocharged GM Detroit Diesel 12V-71T engine in the tractor unit and a turbocharged 465 horsepower GM Detroit Diesel 12V-71T in the scraper, the 333FT was not underpowered by any stretch of the imagination.

Matching six-speed Allison VCLBT5965 transmissions were attached to the 12V-71s and these featured a hydraulic retarder as part of the transmission package along with a variable input torque converter to better apply the machines immense power when loading

Use of the retarder extended the life of the air operated expanding shoe brakes.

The Wabco 333FT was probably the last motor scraper to utilise a bull gear and pinion final drive although strangely the scraper power train employed planetary drives, a most unusual arrangement.

A no spin differential element was standard equipment on both tractor and scraper.

Standard tyres were 33.5×39 E3 on the tractor and 37.5×39 E3 on the scraper, but several options were available to suit varying job requirements.

A top speed of almost 33 miles per hour (52 kph) was attainable, and a fully loaded 333FT at speed was truly an impressive sight.

Twin, dual acting hydraulic cylinders provided the steering. These were quite low mounted on the hitch to keep the weight down low and reduce stress on the scraper gooseneck.

Although manufactured by Wabco, the scraper assembly showed its obvious Hancock heritage in both its design and operation.

Rated at 34 cubic yards, the bowl featured a fixed three-section cutting with sliding floor and bulldozer combination ejection. Five removable teeth could be attached to the centre cutting edge to assist in breaking up hard packed material.

Twin electric motors and reduction gearbox operated the elevator, which had 20 flights. (It should be noted here that the generator which powered these electric motors was mounted to the flywheel of the tractor engine, hence its higher horsepower rating, required to operate the generator.) Bowl lift and ejection were accomplished hydraulically.

The operator had quite a comfortable operating environment with air suspension seat standard. A comprehensive instrument panel bisected the steering column with the machine’s operating controls mounted on a separate panel just to the right of the instrument panel. These all featured short throw levers.

On the floor were the two throttles, brake pedal and the retarder pedal, while the transmission shifter occupied its own special spot just off to the operator’s right hand.

It has to be said that visibility was not as good on this machine as others in the Wabco family but it more than made up for this by its general operating and riding qualities.

Options included a sun canopy, full cab with external ROPS, or ROPS cab with all the trimmings.

Most 333FTs I have seen were fitted with a cab (and with two 12V-71s doing their thing around you this was probably the best option!)

As the machine evolved over its production life there were many different configurations of exhaust pipe and air cleaners trialled and used. By comparing photos to brochures issued by Wabco, one can accurately date when a machine came out of the factory.

From the operator’s seat

I had the very fortunate opportunity to operate a Wabco 333FT during a trip to Cloutman Bros iron sands mining operation at Waiuku during 1980. What a machine! Apart from somewhat limited visibility from the right side of the cab, the 333FT was a joy to operate. Loads of power, very aggressive elevator and an exceptionally smooth ride are still vivid memories.

Its sheer size meant that you had to plan your turns a little in advance but other than that “Thunderbirds were go!”

The New Zealand connection

Industrial Steel & Plant (and later Domtrac) imported a total of three Wabco 333FTs, plus one carcass that was used as a parts source.

The first unit went to work for Cloutman Bros, Waiuku at their NZ Ironsands site in 1971. Second unit went into service for NZ Roadmakers on a housing subdivision in Upper Hutt, Wellington in 1975 while the third unit also went to Cloutman Bros.

Following the demise of NZ Roadmakers, this second machine ended up in Cloutman Bros. ownership as well.

Although Cloutmans has long since divested itself of its 333FTs, at least two operational examples still exist, one in the North Island belonging to Rick Goodman and the other recently delivered to the South Island

For the diecast model collector

Back in the early 1970s, US kitset manufacturer Lindberg issued a 1:60th scale model of the Wabco 333FT. You had to put it together yourself and it had no decals but with a little care, it made up into a very fair (if somewhat small) representation of the real thing.

These kitsets are now long out of production but the occasional one pops up on Ebay from time to time. Expect to pay in excess of US$70 for an example.

Unfortunately this is the only game in town as no other models exist of the machine.

Brief Specifications – Wabco 333FT

Engine (front)  General Motors 12V-71T turbocharged V12 diesel rated at 500hp at 2100 rpm

Engine (rear)                General Motors 12V-71T turbocharged V12 diesel rated at 465hp at 2100 rpm

Transmissions:            Two Allison VCLBT5965 6-speed powershift with variable input torque converter and integral hydraulic retarders

Top Speed:                 32.7mph

Brakes:                        Air operated expanding shoe on all wheels

Std.Tyres                    Tractor: 33.5×39, 38 ply E3

Scraper: 37.5×39 44 ply E3

Steering:                      Full hydraulic, 90° either way

Turning Circle:            39’1”

Capacity:                    34 cubic yards

Operation:                   Hydraulic/Electric

No. of Flights:             20

Chain Speed:   244 ft per minute

Length:                        48’8:

Width:                         12’11”

Height:                        13’10”

Operating Weight:       63 tons (empty), 100 tons (loaded)

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