the guage iadd gauge iaddend 87 without necessitating removal of the cowling an oil supply cover indicated generally by the reference numeral 96 is provided the oil supply cover 96 spans an opening that is formed in the upper cover 89 in proximity to the oil tank 79 and specifically to the cap 86 and gauge 87 this opening is defined by a flange of the cover 89 that receives a gasket 97 so as to sealingly engage the cover 96 when it is closed affixed to the cover 96 is one or more 34 u 34 shaped arms 98 that is connected by means of a pivot pin 99 to a bracket 101 that is affixed to the upper cover 89 contiguous to the opening the oil supply cover 96 is pivotal between a closed position as shown in fig2 and an open position as shown in the broken line view of this figure a torsional spriing iadd spring iaddend 102 operates between the arm 98 and a lug 103 formed on the bracket 101 so as to bias the cover 96 to its opened position the oil supply cover 96 is retained in its closed position by means of a latch mechanism indicated generally by the reference numeral 104 the latch mechanism consists of.