Monthly Generator Exercise Routine & Load Bank Testing Checklist (2026)
Exercising your backup generator monthly for 20 minutes under resistive electrical load burns off internal moisture, keeps seals lubricated, and preserves rotor magnetic field strength for instant storm readiness.
01 Why Running Under Load is Mandatory
Starting a generator and letting it idle with no electrical load does more harm than good. Unloaded engines never reach full operating temperature, creating corrosive acidic moisture inside the crankcase.
Plugging in space heaters or resistive heat loads forces the engine to warm up completely, boiling off moisture and re-polarizing the alternator rotor.
- Boils off water condensation that accumulates inside the oil sump.
- Keeps carburetor fuel bowls fresh and prevents needle valve sticking.
- Preserves alternator residual rotor magnetism for reliable voltage output.
02 Monthly Maintenance Inspection Checklist
Perform this 20-minute exercise routine on the first Saturday of every month to ensure zero surprises when storms strike.
Inspect fuel lines, check oil level with the magnetic dipstick, and test output line voltage.
- 1 Inspect Oil and Fuel: Check oil level on dipstick; verify fresh stabilized fuel or open gas valve.
- 2 Start and Warm Up: Fire engine, disengage choke, and allow two minutes of warm-up idle.
- 3 Apply 50% Electrical Load: Plug in two 1,500W space heaters to draw load and run for twenty minutes.
- 4 Cool Down and Fuel Shutoff: Remove loads, run two minutes to cool, and turn fuel selector to OFF.
- Exercise monthly for 20 minutes under at least 50% resistive load.
- Turn off the fuel valve and let the engine run dry to empty the carburetor.
- Record maintenance hours on an engine Intelligauge logbook.
Frequently Asked Questions
Q: What is the best way to empty the carburetor before storage?
With the engine running, close the manual fuel shutoff valve. The engine will run for roughly two minutes until the carburetor float bowl is completely dry, preventing varnish buildup.
Q: Why did my generator lose its electrical output voltage while sitting?
Alternator rotors can lose their residual magnetic field over months of storage. Running monthly keeps the field saturated; lost fields must be flashed with a 12V battery.