Miller Electric Big Blue 251D manual Generator Power, Engine, Maximum see Section

B. Generator Power

Trouble	Remedy
No output at generator power	Reset circuit breaker CB1 and/or CB2 (see Section 7-1or 7-2).
receptacles.
	Disconnect equipment from generator power receptacles during start-up.
	Have Factory Authorized Service Agent check brushes and slip rings, and field excitation circuit.
Low or high output at generator power	Check engine speed, and adjust if necessary (see Section 8-5).
receptacles.
Low output at optional ac power plant	Check engine speed, and adjust if necessary (see Section 8-5).
junction box, or receptacle RC9.
	If optional remote device is being used, set A/V Control switch in Remote position and remote device at
	maximum (see Section 6-3).
	If optional remote device not being used, set A/V Control switch in Panel position (see Section 6-3).
	Check and replace fuses F1, F2, and/or F3, if necessary (see Section 7-3).
	Have Factory Authorized Service Agent check brushes and slip rings.
No output from optional ac power plant;	Check connections to ac power plant (see Section 7-3).
weld output and standard generator
power receptacle output okay.
	Check fuses F1, F2, and F3 and replace if necessary (see Section 7-3).

C. Engine

Trouble	Remedy
Engine does not start.	Check fuel level. Open fuel valve (see Section 5-4).
	Check optional Magnetic Shutdown switch fuse F and replace if open (see Section 8-6).
	Check battery and replace if necessary.
	Check connections to Engine Control switch.
	Check oil level. Optional automatic shutdown system stops engine if oil pressure gets too low or oil
	temperature gets too high.
	See engine manual.
	Have Factory Authorized Service Agent check engine charging system.
Engine suddenly stops.	Check oil level. Optional automatic shutdown system stops engine if oil pressure gets too low or oil
	temperature gets too high.
	Check optional Magnetic Shutdown switch fuse F and replace if open (see Section 8-6).
Engine slowly stopped; unable to restart	Check fuel level. Open fuel valve (see Section 5-4).
engine.
Engine does not stop when Engine Con-	Use manual shutoff lever to stop engine (see Section 6-1). Check connections to Engine Control switch.
trol switch is placed in Off position.	Have Factory Authorized Service Agent check engine fuel solenoid.
Engine remains at idle speed when	Have Factory Authorized Service Agent check Engine Control switch and idle module.
Engine Control switch is placed in Run/
Idle position and an arc is struck (models
with automatic idle option only.)
Engine will not run at idle speed. (models	Check throttle solenoid fuse F4, and replace if open (see Section 8-6).
with automatic idle option only.)
	Have Factory Authorized Service Agent check Engine Control switch and idle module.
Battery discharges between uses.	Make sure Engine Control switch is in Off position when unit is shut down.
	Clean battery, terminals, and posts with baking soda and water solution; rinse with clear water.
	Periodically recharge battery (approximately every three months).
	Replace battery.
Engine uses oil during run-in period;	Dry engine (see Section 10).
wetstacking occurs.
	See engine manual.

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