23
Venting the fuel system
Venting of the fuel system must be carried out prior to the first start of the engine and
after work has been carried out on the fuel system, when the fuel tank has been run
empty or if the engine has been out of operation for some time.
Venting is carried out as follows: (Regarding location, See Engine Component Guide).
1
Open venting screw on fuel filter about 4 turns. Be careful not to
spill fuel. Use rags around the vent opening.
2
Pump up the fuel by using the hand primer until fuel, free from air
bubbles flows out. Close venting screw. If the pump action is poor,
turn the engine so that the cam driving the pump changes position.
3
If the injection pump has been removed, or when first starting a
new engine, the injection pump must be vented. BOSCH Fuel
Injection pump: Operate the handprimer for approximately half a
minute. The injection pump is then automatically vented.
CAV Fuel Injection pump has two air venting screws, see picture.
Vent No 1 and then No 2. Operate handprimer until fuel free from
air bubbles flows out at screw No 1. Tighten screw No 1. Put
throttle control lever in position full speed and turn engine using
starter motor until fuel free from air bubbles flows out of screw No
2. Tighten screw No.2.
4
Loosen the injector’s delivery pipe nut, push in the stop control and
put the throttle lever in full speed position. Turn the engine using
the starter motor until fuel flows out of the delivery pipes. Be
careful not to spill fuel! Use rags around the venting location.
Tighten the delivery pipe nuts and start the engine.
CHECKS AND SERVICE
