ENGINE 6A 4 nnn Fig 6A 2 Engint Cram This camshaft deviates from a conventional camshaft design in that each of three exhaust valve lobes are twice the width of the intake valve lobes and actuate a pair of exhaust valve lifters The camshaft journals ride directly on the machined base metal of the crankcase Thrust of the camshaft is taken by a thrust washer located between the camshaft gear and front bearing A forged steel crankshaft is housed above the camshaft between the split halves of the crankcase The crankshaft has six throws arranged in pairs each crankpin being removed 180 from the other member r r r o Section Across Crankshaft of its pair Pairs are located 60 apart No separate main bearing caps are required since the four steelbacked babbit bearings are supported entirely by the crankcase halves The crankshaft drives the camshaft through a composite gear and drive hub The front crankshaft seal is installed to the cast aluminum clutch housing or flywheel housing which mounts to the front of crankcase assembly Pistons are the conventional flat head aluminum alloy type with cast in steel struts Each piston is coated with a light tin plate and utilizes two compression rings and a two piece oil control ring The piston