selector to desired setting, so that necessary
metal application, no change of current is de-
arc can be produced.
sired. During welding for this purpose, job
selector should be set in black section for a
medium-high open-circuit voltage (normal
Coated Electrodes
welding range). Little current change will re-
Lengths
Electrode diameter
Current
mlexcitmoum
Ea r de
sult from lengthening or shortening arc when
(in.)
(in.)
minimum
(amps) (amps)
job selector is in this position.
70
11 1/2
3/32
90
(3) When a "rubbery" arc or large elec-
110
14 or 18
135
1/8
trodes and high currents is desired for welding
14 or 18
180
150
5/32
operation, job selector should be set in the
180
14 or 18
220
3/16
yellow section for a high open-circuit voltage
1/4
250
300
14 or 18
300
425
14 or 18
(large electrodes range) .
5/16
450
14 or 18
3/8
550
(4) For special jobs requiring the small-
est sizes of electrodes and very low current
values, job selector should be set in the special
and Slag Types of Electrodes
applications section for a low open-circuit
Gaseous types
voltage.
Slag type
Flat position Vertical and
Electrode
(amps)
overhead
diameter
(5) The approximate current range for
position
(in.)
positions
(amps)
(amps.)
bare and lightly coated electrodes is shown in
60
60
3/32
130
110
for gaseous and slag types of electrodes.
120
1/8
160
150
140
5/32
c. Dual Control. Dual control of amperage
200
160
175
3/16
and voltage can be accomplished by use of job
300
200
1/4
selector and continuous current control. The
400
325
5/16
dual control is utilized by the following steps:
500
425
3/8
(1) Place polarity switch (fig. 2-2) in
d. Operation as an Arc Welder.
the OFF position.
(1) Refer to paragraph 2-12 and start
(2) Start engine in accordance with para-
engine.
graph 2-12 and allow it to warm up.
(2) Connect welding cables to terminals
(3) Place the polarity switch in ELEC-
TRODE POSITIVE or ELECTRODE NEGA-
TIVE as required.
(3) Place polarity switch in desired posi-
tion (fig. 23).
(4) Set job selector (fig. 2-2) to desired
voltage.
(4) Place job selector in proper position
(5) Set current control (fig. 2-2) to de-
sired amperes.
(5) Set current control in corresponding
(6) Strike an arc.
color range (fig. 2-3 ).
(7) If arc is weak, turn job selector up.
If arc is too cold, turn current control up 10
(1) Refer to paragraph 2-12 and start
or 20 amperes and turn job selector down.
engine.
Warning: Do not adjust welding con-
(2) Place idle control switch in OFF po-
trols while maintaining arc.
sition (fig. 23).
(8) If, when correct current is obtained,
( 3 ) Place auxiliary generator circuit
job selector is positioned beyond desired set-
breaker in ON position (fig. 2-3).
ting, adjust current control up and return job
Section V. OPERATION UNDER UNUSAL CONDITIONS
antifreeze. Before adding initial antifreeze,
clean and flush the entire cooling system in
OF.)
a. Lubricate the engine in accordance with
accordance with paragraph 3-39. Inspect cool-
the current lubrication order.
ing system for signs of leaks or other damage.
b. Inspect the engine cooling system to as-
Inspect shutter control for proper operation.
sure that it contains the proper mixture of
Caution: Do not bend or kink coolant
AGO 20030A
