David Owen, January 20, 2011.
Click on images to view larger picture.
Based on the Mills 1.3cc Mk2 diesel, the D.S. 1.3 was manufactured by D.S. Small Engineering in rural Hurstbridge, a town roughly 30km north east of Melbourne, Vistoria (Australia). The engine was developed by David Strutt and limited production commenced sometime in the mid'90s. The engine depicted is #12 of a total production of 20 engines.
David investment-cast the cases and venturis from his own lost wax dies, using candlewax. This is not a very satisfactory material for investments and the crankcase castings, whilst mechanically sound, are not particularly neat. All other parts in the D.S. 1.3 Diesel are very nicely machined and fitted and the engines start and run very well.
The rear-mounted throttle and tank assembly is of particular interest and is a stand-out feature of these engines. The nva is located in a rotating throttle barrel, the idle position of which is set by a small screw. On the other side of the venturi, it is just possible to see the small airbleed hole which is uncovered and weakens the mixture as the throttle arm is moved to close the barrel towards idle.