Engine Diagrams B3.9, B4.5, B5.9 Industrial Page E-6 Section E - Engine and System Identification Engine Diagrams Engine Views Left Side View - B3.9 Industrial 1. Engine air inlet 2. Fuel filter/water separator 3. Fuel inlet connection 4. Magnetic pickup location (3/4-16 UNF) 5. Fuel lift pump 6. Crankcase breather tube 7. Lubricating oil dipstick 8. Fuel drain connection 9. Front engine mounting bracket 10. Engine dataplate 11. High pressure fuel lines 12. Fuel injection pump 13. Intake air preheater (optional).