When a storm rolls through New Hampshire or the power grid falters, your generator isn’t just equipment—it’s a lifeline. But even the most reliable generators need regular attention to perform at their best. Whether you’re powering up a lakeside cabin in the White Mountains or keeping your Seacoast small business running, understanding generator troubleshooting can prevent headaches and expensive repairs.
At Seacoast Power Equipment, we’ve seen it all—from dead batteries in December to overheating issues in July. In this expert guide, we’ll walk you through the most common generator issues and offer step-by-step generator troubleshooting tips to get you back up and running fast.
Top Generator Issues & How to Spot Them
Let’s start with the most common problems you’ll encounter. These are the top issues our technicians repair during generator service appointments across New Hampshire.
1. Engine Won’t Start
Probable Causes:
- Empty fuel tank or stale fuel
- Dead battery
- Dirty or faulty spark plug
- Engaged safety switch
Quick Fixes:
- Refill with clean, fresh fuel
- Test battery voltage (should be ≥12.4 volts)
- Clean or replace the spark plug
- Consult your manual for reset instructions on safety switches
This is the #1 call we receive from customers in Portsmouth and Dover. Most of the time, it’s as simple as a dead battery or gummed-up fuel.
2. Unusual Noises
If your generator sounds different than usual, don’t ignore it.
Types of Noises:
- Knocking or pinging: Low-quality fuel or timing issues
- Hissing: Fuel leak—shut it down immediately
- Screeching: Belt or bearing wear
- Banging: Loose bolts or components
Catch it early and you could prevent a complete breakdown. If you’re unsure, bring it to our shop for a full diagnostic.
3. Overheating
New Hampshire summers are short—but they can still push your generator past its comfort zone.
Why It Happens:
- Clogged vents or cooling fins
- Low oil or coolant
- Malfunctioning thermostat
- Blocked radiator
Tip: Keep your generator clean and make sure airflow is never restricted, especially during summer mower and generator tune-ups.
4. Power Output Fluctuations
Symptoms:
- Lights flicker or appliances reset
- Generator surges or stalls
What to Check:
- Overloaded circuits
- Dirty air filter
- Carburetor issues
- Electrical wiring problems
Inconsistent power is a red flag and could damage sensitive electronics. Don’t take chances—schedule service at the first sign of this issue.
Step-by-Step Generator Troubleshooting Tips
Before you call in the pros, try these practical DIY steps to narrow down what’s wrong.
1. Visual Inspection
Always start with a walkaround. Look for:
- Fuel or oil leaks
- Loose wires or connectors
- Corrosion on battery terminals
- Damaged fuel lines
- Dirty air filters
A good flashlight and clean rag can go a long way during a quick inspection.
2. Check Fuel & Oil
- Fuel: Is the tank full? Is the fuel fresh? Old gas can clog the carburetor.
- Oil: Check levels and color. Milky or black oil means it’s time to change it.
For step-by-step guidance on oil changes, check out our post on summer mower maintenance—the same principles apply to small engines.
3. Battery Test
Use a multimeter:
- 12.6–12.8 volts = good
- Below 12.4 = recharge or replace
Clean battery terminals with a wire brush and check for corrosion. This simple step solves about 30% of the generator issues we see in winter.
Advanced Generator Diagnostics
If basic troubleshooting doesn’t fix it, you might need to dig deeper—or bring your unit to Seacoast Power’s certified techs for a full workup.
1. Electrical Testing
- Fuses and Breakers: Check for continuity. Replace if blown.
- Ignition System: Test spark plug, coil, and gap settings.
- Voltage Output: With a multimeter, test the outlet. If there’s no output, internal wiring or alternator issues may be at play.
Some higher-end models include onboard diagnostics—if you have a Kress or Honda generator, consult the manual or give us a call for help interpreting error codes.
2. Cooling System Checks
- Clean the radiator
- Check coolant level and top off if needed
- Inspect fan belts and hoses
- Verify thermostat operation with a heat test
Overheating is especially common in standby units that aren’t tested monthly. We recommend scheduling regular inspections as part of our seasonal generator tune-ups.
Preventative Maintenance That Saves You Money
Preventative care is the most cost-effective strategy for avoiding generator failure. Here’s a maintenance checklist we recommend for all New Hampshire homeowners:
Monthly Checks:
- Start the generator and let it run for 10–15 minutes
- Check battery voltage and electrolyte levels
- Inspect for pests or rodent nests
Every 6 Months:
- Change the oil
- Replace air and fuel filters
- Clean cooling fins
- Test the output voltage
Annually:
- Schedule a full inspection with Seacoast Power
- Replace spark plugs and inspect exhaust system
- Pressure-test fuel lines and replace if cracking
Need parts? Visit our Generator Parts & Accessories section or call to order custom components for Briggs & Stratton, Kohler, Generac, and more.
Proper Generator Storage in New Hampshire Weather
The way you store your generator—especially during long off-seasons—can make or break its lifespan.
Storage Tips:
- Drain the fuel: Or add a stabilizer to avoid gumming up the carburetor
- Clean the unit: Remove all grass, oil, and grime
- Store indoors: A shed or garage is ideal—dry, ventilated, and rodent-proof
- Remove battery: Store separately in a cool, dry place and trickle charge monthly
- Cover it right: Use a breathable cover that won’t trap moisture
If you’re preparing your whole property for winter, see our full cold-weather equipment prep guide.
Frequently Asked Questions
What are the most common generator problems?
Most issues stem from dead batteries, old fuel, clogged air filters, or worn spark plugs. Overheating and poor electrical output are also common, especially with lack of maintenance.
How do I troubleshoot a generator that won’t start?
Start with fuel and battery checks. Inspect the spark plug and look for tripped safety switches or breakers. If that doesn’t work, bring it to Seacoast Power Equipment for diagnostics.
Why is my generator making a weird noise?
Knocking, screeching, or hissing noises usually mean mechanical problems or loose components. Shut it off and inspect belts, fuel lines, and mounts—or let our techs take a look.
Can I fix a generator overheating issue myself?
Yes—start by cleaning the radiator and checking coolant levels. Make sure nothing’s blocking airflow. If the problem persists, the thermostat or water pump may need attention.
How often should I service my generator?
We recommend a basic inspection every 6 months and a full tune-up once a year. Visit our service page to schedule your generator maintenance today.
How should I store my generator for the off-season?
Drain the fuel, clean the unit, and store it in a dry, protected area. Disconnect and maintain the battery to ensure it’s ready next season.
Why New Hampshire Trusts Seacoast Power for Generator Service
Whether you’re maintaining a home generator in Exeter, troubleshooting a commercial unit in Rochester, or storing a portable generator at your lakeside retreat in Wolfeboro, Seacoast Power Equipment is here to help.
✅ Factory-certified technicians
✅ Pickup and delivery available
✅ Parts and service for top brands like Honda, Generac, Kohler, Kress, and more
✅ Convenient scheduling and seasonal tune-up plans
Don’t wait until the lights go out. If you’re facing generator issues, need fast diagnostics, or want to stay ahead of problems with regular maintenance, contact Seacoast Power Equipment today. Let’s keep your generator running strong—year-round.