Historic Terex S24 Scraper Donated for Display in Twizel

A significant addition to a specialized machinery display has occurred with the donation of a Terex S24 scraper by philanthropist and director of the Rooney Group, Gary Rooney. This scraper is now part of an exhibition showcasing earthmoving equipment that played a crucial role in the Upper Waitaki Power Development project in New Zealand.

The Terex S24, alongside other notable machinery like the Caterpillar 631 and International 295, was instrumental in excavating and placing materials to create the canals connecting Lakes Tekapo, Pukaki, and Ohau. These canals were essential for various hydroelectric projects, including the Pukaki High Dam and the powerhouse sites at Tekapo B, Ohau A, B, and C.

Earlier last month, the Rooney Group transported the S24 scraper to Temuka for refurbishment. The machine underwent sandblasting and painting before being placed on display. Rick Ramsay, convener of the Heritage Group, highlighted the importance of this addition, stating, “There are a lot of operators who will fondly recall the distinctive roar of these machines, and to again see one in the Mackenzie Basin on display is a big addition.”

The S24 scraper, powered by a V12 General Motors two-stroke diesel engine, features an Allison CLBT-5865 six-speed powershift transmission with a top speed of 50 km/h. Its bowl capacity is 18 cubic meters struck or 24 cubic meters heaped. Despite its robust 400 horsepower engine and differential lock to minimize wheelspin, the scrapers were primarily push-loaded by bulldozers during the Upper Waitaki project due to the dense glacial moraine deposits encountered.

Clyde Engineering sold a total of 32 S24 scrapers in New Zealand, with the majority utilized in hydro schemes. Notable fleet operators included Higgins Earthmoving, Earthmovers Waikato, McBreen-Jenkins, Burnetts Motors, and Doug Hood Ltd. The construction arm of Doug Hood Ltd was acquired by Gary Rooney around 1998, which included the S24 scrapers.

These machines are renowned for their rugged construction and ease of maintenance, allowing many to be rebuilt and remain in operation across various projects even today. Some units were repurposed as “dump trucks,” allowing for efficient loading and distribution of materials, enhancing their utility in earthmoving tasks.

The S24 donated to the Twizel display was one of three purchased by the Rooney Group from the North Island specifically for the company’s Rangitata South irrigation Scheme, a substantial private investment exceeding $130 million. These units were exclusively utilized for this project and have since been stored at the company’s depot in Ashburton.

The addition of the Terex S24 scraper not only enriches the historical narrative of earthmoving machinery in New Zealand but also pays tribute to the engineering feats achieved during the Upper Waitaki Power Development.