How To Eliminate Air From The Fuel System - Lincoln Electric SHIELD-ARC SVM128-A Service Manual

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HOW TO ELIMINATE AIR FROM THE FUEL SYSTEM

There are two methods to eliminate air from the fuel
system according to the type of pump fitted:
See Figure D.3. The standard method is used where
the fuel injection pump has vent screws 4 and 5.
The self-vent method is used where the fuel injection
pump has a self-vent feature. Vent screws are not fit-
ted to these pumps. No connections or plugs need to
be released to eliminate air from the fuel system.
If air enters the fuel system, it must be eliminated
before the engine can be started.
Air can enter the system if:
• The fuel tank is drained during normal operation.
• The low-pressure fuel pipes are disconnected.
• A part of the low-pressure fuel system leaks during
engine operation.
In order to eliminate air from the fuel system, proceed
as follows:
FIGURE D.3 – ELIMINATING AIR FROM THE FUEL SYSTEM
1
MAINTENANCE
Standard method
1. See Figure D.3. Loosen the banjo connection bolt
which is fitted on the top of the filter (1).
2. See Figure D.3. Operate the priming lever on the
fuel lift pump (2) until fuel, free from air, comes from
the filter vent point. Tighten the banjo connection
bolt. If the drive cam of the fuel lift pump is at the
point of maximum cam lift, it will not be possible to
operate the priming lever.
crankshaft must be turned one revolution.
3. See Figure D.3. Where the fuel filter is fitted lower
than the fuel injection pump, loosen the inlet con-
nection at the fuel injection pump (3) and operate
the lift pump to remove any air. Tighten the inlet
connection.
4. Ensure that the manual stop control is in the "run"
position. If an electrical stop control is used, turn
the start key to the "R" position.
5. See Figure D.3. Loosen the vent screw in the lock
screw of the hydraulic head (4) and the vent screw
on the governor cover of the fuel injection pump (5).
6. Operate the priming lever of the fuel lift pump until
fuel, free from air, comes from the vent screw(s).
Tighten the vent screw(s).
2
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In this situation, the
3
5
4