Miller Electric Big 40G Adjusting Optional High Altitude Carburetor, Troubleshooting, Welding

7-11. Adjusting Optional High Altitude Carburetor

Y 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.

2 1 Y Stop engine.

Close door.

Tools Needed:

1/2 in

Ref. ST-159 727-B / Ref. ST-115 155-A

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.

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