Labels:text | screenshot | font OCR: ORIFICE In this context, an orifice is a small passage of precise dimensions used to control the flow of fuel. In a carburator, for example, orifices are used to control Idle and Main Jet fuel flows. P-V DIAGRAM A P-U or Pressure-Volume diagram is a method of showing the relationships of piston position, and pressure in a reciprocating engine or pump. Also known as an Indicator Diagram, when Indicator recorders were used to measure engine performance. RETARDER A braking system which uses either modified valuing in the engine (ususally Diesel) or a separate brake (hydraulic turbine or electric generator and load) to control vehicle speed on downgrades.
