FUEL TANKS, LINES, FILTERS, and PUMPS CBCAUTOMOTIVERKCBCAUTOMOTIVERK

OBJECTIVES u Describe fuel tank design & mounting. u Describe a fuel tank filler and filler cap. u Describe three types of fuel lines. u Explain four types of fuel line fittings. u Describe in-line fuel filter design. u Explain fuel filter mounting carb & EFI. u Explain fuel filter located in carb inlet nut. CBCAUTOMOTIVERKCBCAUTOMOTIVERK

OBJECTIVES u Explain the operation of a mechanical fuel pump during the intake stroke. u Explain the operation of a mechanical fuel pump during fuel discharge. u Explain how the fuel pressure is limited in a mechanical fuel pump. u Describe the operation of an electric fuel pump. CBCAUTOMOTIVERKCBCAUTOMOTIVERK

INTRODUCTION u Leaking fuel tanks create a very hazardous situation. u Filtering must be done without restricting flow. u Fuel system must provide adequate volume and pressure. CBCAUTOMOTIVERKCBCAUTOMOTIVERK

FUEL TANKS u Plastic or steel? u Retained with two straps. u Contains sending unit and pump. CBCAUTOMOTIVERKCBCAUTOMOTIVERK

FUEL LINES and FITTINGS u Three types of fuel lines: l Steel l Nylon l Reinforced Rubber u Four types of fuel fittings: l Pipe thread l Inverted Flare l Hose clamp l Captured O’ring or gasket CBCAUTOMOTIVERKCBCAUTOMOTIVERK

FITTINGS CBCAUTOMOTIVERKCBCAUTOMOTIVERK

FUEL FILTERS u Replace every 15,000 to 30,000 miles u Metal or plastic housing u Filter media l Pleated Paper l Plastic screen l Sintered Brass CBCAUTOMOTIVERKCBCAUTOMOTIVERK

FILTER LOCATION u Mechanical in engine compartment. u Electric under vehicle. CBCAUTOMOTIVERKCBCAUTOMOTIVERK

MECHANICAL FUEL PUMPS u Operates off eccentric on camshaft. u Return spring keeps fuel pump arm in contact with camshaft. u Two check valves l Inlet l Outlet u Diaphragm spring determines fuel pressure. CBCAUTOMOTIVERKCBCAUTOMOTIVERK

FUEL PUMP OPERATION CBCAUTOMOTIVERKCBCAUTOMOTIVERK

ELECTRIC FUEL PUMPS u Two types l Low pressure 10 to 15 PSI l High Pressure 30 to 45 PSI l Some up 60 PSI CBCAUTOMOTIVERKCBCAUTOMOTIVERK

CIRCUITS u Must have a way to keep fuel from draining from the vehicle in a rollover. l Oil pressure switch l Inertia switch l Computer u All use a relay CBCAUTOMOTIVERKCBCAUTOMOTIVERK

DIAGRAM CBCAUTOMOTIVERKCBCAUTOMOTIVERK