Miller Electric Big 40G, Owner'S Manual

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OM-477 Page 31
7-11. Adjusting Optional High Altitude Carburetor
Ref. ST-159 727-B / Ref. ST-115 155-A
A too lean air-fuel mixture
can damage valves. Do not
adjust main adjustment
screw so air-fuel mixture is
too lean.
Carburetor can be equipped with an
adjustable main jet for operation
above 4000 ft (1219 m). Adjust car-
buretor as follows:
Start engine and apply nearly full
load to welding generator.
1 Main Adjustment Screw
2 Lock Nut
Loosen nut. Turn screw in until en-
gine falters (lean air-fuel mixture).
Turn screw out until engine runs
smoothly, then turn screw out an
additional 1/4 turn. Tighten nut.
Stop engine.
Close door.
Tools Needed:
1/2 in
1
2
7-12. Troubleshooting
A. Welding
Trouble Remedy
No weld output. Check control settings.
Place optional Output (Electrode) Control switch in On (Hot) position, or move switch to Remote posi-
tion and connect remote contactor to Remote 14 receptacle RC3 or terminal strip 3T (see Sections
4-7, 4-8, and 5-1).
Check and secure connections to optional Remote 14 receptacle RC3 or terminal strip 3T (see Sec-
tions 4-7 and 4-8).
Disconnect equipment from 120 volt ac receptacles during start-up.
Have Factory Authorized Service Agent check brushes and slip rings, and field current regulator board
PC1.
Erratic weld output. Check and tighten connections inside and outside unit.
Use dry, properly-stored electrodes.
Remove excessive coils from weld cables.
Be sure connection to work piece is clean and tight.
Have Factory Authorized Service Agent check brushes and slip rings.