AIR CLEANERS AND FUEL SYSTEM-N.4 Pressure Checking of Fuel Lift Pump in Position 4. Examine the rocker arm, operating lever, rocker arm retaining pin and rocker arm return spring for wear. Replace any parts where necessary. Fit a 0-10 Ibflin 2 (0-0,7 kgflcm2) or 0-70 kN/m 2 pressure gauge to the outlet of the pump. Ensure that there are no leaks at the connections between pump and gauge. Crank the engine for 10 seconds and note the maximum reading on the gauge. If the pressure recorded is less than 75% of the minimum production static pressure shown below, then rectify the pump. Also observe the rate at which the pressure drops to half the maximum figure obtained when cranking has ceased.
If less than 30 seconds, rectFfy the pump. 5. Replace all joints, seals and washers as routine procedure. 6. Examine upper and lower castings for wear or distortion. Slight distortion of flanges can be remedied by grinding the flange face to restore flatness. To Re-Assemble the Lift Pump Minimum Production Static Pressure Minimum Test Pressure (75% of Minimum Production Pressure) Ibflin 2 kgflcm2 kN/m 2 Examine the casting and ensure that there is sufficient material to provide a sound staking when new valves are fitted. Ibflin 2 kgflcm2 kN/m 2 Clean the valves recesses to allow the new valves to be correctly fitted. 4 bolt type 2 bolt type 6 0,42 41 6 0,42 41 4.5 0,31 31 4.5 0,31 31 1.
Insert a new valve gasket in each valve recess. 2. Place the new valves in the recesses. The valve in the inlet port should be fitted with the spring outwards (i.e., towards the diaphragm flange) and To Remove the Lift Pump 1. Disconnect the pipes from the inlet and outlet ports. Seal the ends of the pipes to prevent the entry of foreign matter. 2. Remove the two nuts and washers holding the pump to the tappet inspection cover. Withdraw the pump, distance piece and joints. To Dismantle the Lift Pump 1. Before dismantling, make a file mark across the flanges for location purposes when the pump is being re-assembled. 2.
Remove the five cover screws and separate the two main castings, then remove the diaphragm assembly from the lower half by turning the dia- phragm through 90' in either direction. NOTE: The diaghragm and pull rod assembly is a permanent assembly and no attempt should be made to separate the parts. 3. Remove the retaining clip from one side of the pump body and push out the rocker arm retaining pin. Withdraw the rocker arm, etc., from the body. 4. Prise out the valves with a screwdriver or other suitable tool. Inspection I. Check the diaphragm assembly and renew if the material is split or cracked, or if serious wear is apparent in the link engagement slot. 2.
The diaphragm spring should be replaced if faulty or corroded. A new spring should have the same colour identification (Refer to Page B.11). 3. Replace the valves unless they appear to be in per- fect condition. N8