Generator Maintenance Guide | PES Supply

Generator Maintenance Guide

Keep your generator running reliably with this complete maintenance schedule

Maintenance Schedule

Interval Portable/Inverter Standby
Every Use Check oil, clean debris Auto-exercise (weekly)
25 hours Check/clean air filter —
50 hours First oil change First oil change
100 hours Change oil, clean filter Check battery
200 hours Replace air filter, spark plug Change oil + filter
500 hours Major service (valves) Replace spark plugs, air filter
Annual Full inspection + oil change Professional service
2 years Replace fuel lines Replace battery, fuel filter

Oil Type and Capacity

Generator Size Oil Type Capacity Change Interval
2,000-3,000W 10W-30 synthetic 0.4-0.6 qt 50 hrs
5,000-8,000W 10W-30 synthetic 0.6-1.0 qt 100 hrs
10,000-15,000W 5W-30 synthetic 1.2-2.0 qt 100 hrs
20,000W+ 5W-30 synthetic 2.0+ qt 200 hrs or annual

Winterization

For generators stored during winter:

  1. Add fuel stabilizer to tank, run 10 min to circulate
  2. Change oil before storage
  3. Remove spark plug, add teaspoon of oil, pull cord to coat cylinder
  4. Store in dry, covered location
  5. For standby: install cold weather kit (oil heater, battery warmer)

Troubleshooting Common Issues

Problem Likely Cause Solution
Won't start Stale fuel / low oil Drain fuel, add fresh. Check oil level.
Runs rough Dirty carburetor Clean carb, add fuel injector cleaner
Low voltage Overloaded / worn brushes Reduce load. Check AVR.
No power output Tripped breaker / lost residual magnetism Reset breaker. Flash the field.
Surging Fuel starvation / dirty governor Clean fuel system. Adjust governor.
Standby won't auto-start Dead battery / faulty controller Check/replace battery. Test controller.

Standby Generator Battery Maintenance

Standby generator batteries typically last 2-3 years. To extend life:

  • Check battery voltage monthly (should be 12.6V+)
  • Clean terminals with baking soda and wire brush
  • Apply dielectric grease to prevent corrosion
  • Replace every 3 years regardless of condition
  • Use a battery tender/maintainer if generator sits unused