Generator Maintenance: Essential Tips to Prevent Site Downtime

Why Maintenance Matters

A well-maintained diesel generator can run for 10,000 to 30,000 hours. A neglected one might fail after just 2,000. On a construction site or during an event, that failure costs thousands in lost time and damaged reputation.

The 250-Hour Service Checklist

Every 250 running hours or 3 months (whichever comes first), complete these checks:

Daily Checks

• Check oil level with the dipstick — top up if below the full mark
• Check coolant level in the radiator — never open while hot
• Inspect for fuel leaks around hoses and fittings
• Check battery terminals for corrosion — clean if needed
• Listen for unusual noises — knocking, whining, or rattling

Weekly Checks

• Replace fuel filter if pressure gauge shows restriction
• Clean or replace air filter — hold it up to light; if you cannot see light through it, replace it
• Check drive belts for tension and cracking
• Test the alternator output with a multimeter
• Run the generator under load for at least 30 minutes

Monthly Checks

• Change the engine oil and oil filter
• Inspect exhaust system for leaks and corrosion
• Check all electrical connections for tightness
• Test auto-mains failure (AMF) transfer if fitted
• Inspect radiator cap and coolant condition

Common Failure Points

1. Clogged Fuel Filters

Dirty fuel is the number one cause of generator failure. Water and sediment accumulate in the tank over time. Replace fuel filters regularly and keep the tank full to reduce condensation.

2. Dead Batteries

A generator that will not start usually has a flat battery. Test battery voltage monthly and replace every 2-3 years regardless of condition.

3. Overheating

Low coolant, blocked radiators, or failed thermostats cause overheating. Clean radiator fins with compressed air and check coolant quality every service.

Keep a Maintenance Log

Record every service, every fault, and every hour run. This log:

• Helps predict when parts will need replacement
• Provides evidence of compliance for WHS audits
• Increases resale value if you sell the generator
• Helps our technicians diagnose issues faster if you hire from us

Professional Servicing

While daily and weekly checks can be done on-site, manufacturer-spec servicing requires qualified technicians with the right diagnostic tools. Hanson Hire provides full servicing on all hired generators — contact us to schedule a service.