Historic Terex S24 Scraper Donated to Upper Waitaki Display

A Terex S24 scraper, generously donated by philanthropist and director of the Rooney Group, Gary Rooney, is now on display at the Upper Waitaki Power Development exhibition. This addition highlights the significant role that earthmoving machinery played in the creation of vital infrastructure linking Lakes Tekapo, Pukaki, and Ohau, as well as supporting various dams and powerhouse sites in the region.

The S24 scrapers were integral to excavation and material placement during the Upper Waitaki project, alongside machines from Caterpillar and International. Last month, the Rooney Group transported the S24 to Temuka for restoration, including sandblasting and repainting, prior to its unveiling at the exhibition.

Rick Ramsay, convener of the Heritage Group, expressed his excitement about the donation, 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.” He emphasized the generosity of Mr. Rooney in not only donating the scraper but also facilitating its transport.

The Terex S24 is powered by a V12 General Motors two-stroke diesel engine, coupled with an Allison CLBT-5865 six-speed powershift transmission. This configuration allows the machine to reach a top speed of 50 kph. The transmission system features a hydraulic retarder to enhance braking efficiency. With a bowl capacity of 18 cubic meters struck or 24 cubic meters heaped, the S24 scrapers were robust and versatile.

Despite their impressive specifications, including over 400 horsepower and a differential lock to prevent wheel spin, the scrapers were often push-loaded by bulldozers during the Upper Waitaki project. This was necessary due to the compacted nature of the glacial moraine deposits prevalent in the area.

A total of 32 S24 scrapers were sold into New Zealand by Clyde Engineering, with many employed on hydro schemes across the country. Notable fleet operators included Higgins Earthmoving, Earthmovers Waikato, McBreen-Jenkins, Burnetts Motors, and Doug Hood Ltd.

Gary Rooney acquired the construction division of Doug Hood Ltd in approximately 1998, which included the S24 scrapers. Their rugged design and ease of maintenance led to many being refurbished and reused on various projects, some even functioning as “dump trucks” after modifications. This adaptability allowed for efficient loading by diggers and effective material distribution.

The specific unit donated to the Twizel display is one of three purchased by the Rooney Group from the North Island for use on the company’s Rangitata South irrigation Scheme, a private initiative costing over $130 million. These units were utilized solely for this project and have been stored at the company’s depot in Ashburton since the completion of their work.

The inclusion of the Terex S24 scraper in the exhibition not only celebrates the engineering marvels of the past but also serves as a reminder of the enduring legacy of the Upper Waitaki Power Development.