Generator Maintenance Tips: Extending Equipment Life

Why Preventive Maintenance Matters#

A generator that sits idle for months and then fails during a power outage is worse than having no generator at all — it creates a false sense of security. Regular preventive maintenance is what separates a reliable emergency power system from an expensive paperweight.

Well-maintained generators typically last 20,000–30,000 running hours. Neglected units can fail in under 5,000. The difference isn't the equipment — it's the maintenance program behind it.

Monthly Maintenance Checklist#

These items should be checked every month, ideally during your required NFPA 110 monthly load test:

Visual Inspection#

• Check for oil, coolant, or fuel leaks around the engine, hoses, and connections
• Inspect the air intake and exhaust for obstructions (bird nests, debris, ice)
• Verify the block heater is functioning (engine should be warm to the touch)
• Check control panel for fault codes or warning indicators
• Inspect the enclosure or housing for damage, rust, or water intrusion

Fluid Levels#

• Engine oil — check level on dipstick; look for discoloration or contamination
• Coolant — verify level in the overflow tank and check concentration with a refractometer
• Fuel — verify day tank and main tank levels; check for water in fuel via sight glass or drain

Battery System#

• Check battery terminal connections for corrosion (clean with baking soda solution if needed)
• Verify battery charger output voltage (typically 13.5–14.2V for lead-acid)
• Test battery voltage under load — a battery that reads 12.6V at rest but drops below 10V under starter load needs replacement

Quarterly Maintenance#

Every three months, add these items to your routine:

• Fuel system: Replace fuel/water separator filters, check fuel lines for cracking or chafing
• Air filter: Inspect and replace if restricted (or per manufacturer interval)
• Belt inspection: Check alternator and water pump belts for tension, cracking, and glazing
• Coolant hoses: Squeeze hoses to check for softness, bulging, or brittleness
• Transfer switch: Exercise the ATS in test mode and verify transfer and retransfer timing

Annual Service Items#

Your annual service should be performed by a qualified generator technician and includes:

Common Maintenance Mistakes#

Running without load. Generators need to work. Running at less than 30% load causes wet-stacking in diesel units — unburned fuel accumulates in the exhaust system, reducing performance and eventually damaging components. If your facility doesn't draw enough load during monthly tests, schedule periodic load bank testing.

Ignoring coolant. Coolant isn't just water — it contains corrosion inhibitors that protect the engine block, cylinder liners, and water pump. These inhibitors deplete over time even if the coolant looks clean. Test annually and replace every two years.

Skipping battery maintenance. Starter batteries are the single most common point of failure. A generator with a perfectly maintained engine won't start if the battery is dead. Test batteries under load quarterly and replace them proactively every 3–4 years.

Forgetting the enclosure. Outdoor generators face rain, UV, rodents, and insects. Inspect weatherproof enclosures for seal integrity, drainage, and pest entry points. A small gap can let a mouse build a nest on the wiring harness.

Building a Maintenance Program#

The most reliable approach is a planned maintenance agreement with a qualified service provider. This ensures:

• Scheduled service at the right intervals
• Genuine OEM parts and correct fluids
• Documentation that satisfies NFPA 110 and insurance requirements
• Priority emergency response when you need it most

OnPoint Generators offers comprehensive maintenance programs for all major brands including Generac, Kohler, and Cummins. We service commercial and residential generators across Northern California.

Schedule a maintenance consultation to protect your investment and ensure your generator is ready when you need it.