Both of these 7½ horsepower Allan Brothers engines were built at the Ashgrove Engineering Works in Aberdeen, Scotland and sold in Adelaide, Australia by Bagshaw & Sons, Ltd.

The engine in the upper picture is the older of the two, being built in 1910. It originally had hot tube ignition but was converted to cold starting by Kaeysler Brothers of Hahndorf. The modification consisted of the installation of a Fellows magneto and a carburetor that Kaeysler installed on their own engines. This engine was used to power a saw bench in Murray Bridge, South Australia.

The engine pictured on the trailer is the newer of the two, being built in 1911. It was used to pump water from the Finnis River in South Australia. It is completely original with the continuous lamp hot tube ignition.

The speed of both engines is regulated via flyball governors. As engine speed increases, centrifugal force moves the flyballs outward. This outward movement moves a lever which holds the exhaust valve open, causing the engine to stop the intake of fuel and to slow down. When the speed slows down sufficiently, the flyballs fall inward, releasing the lever and allowing the engine to once again fire and increase speed.