A generator won’t stay running when there’s a problem with fuel flow, air intake, or an electrical safety sensor shutting it down. The most common reasons include low oil levels, a clogged carburetor, or faulty wiring.
Learn more about what to check when your generator will not start to avoid unnecessary downtime. Addressing these issues early prevents damage and restores reliable power.
At Grounded Electric, our licensed electricians quickly identify and fix these problems for both residential and commercial systems. Led by Robert “Bobby” Mulholland and project manager Barret Abramow, our team delivers safe, code-compliant solutions that keep your generator running smoothly and consistently.
Key Takeaways
- Most generator shutdowns are caused by fuel, air, or electrical imbalances that trigger built-in safety systems.
- Routine checks of oil level, fuel quality, and wiring connections can prevent most “generator won’t stay running” issues.
- Portable, standby, and RV generators each have unique failure patterns that require tailored troubleshooting steps.
- Replacing small components like spark plugs, filters, or voltage regulators often resolves stalling without major repairs.
- Professional inspections by Grounded Electric, led by Bobby Mulholland and Barret Abramow, ensure long-term reliability and code compliance.
Understanding the “Generator Won’t Stay Running” Problem
A generator won’t stay running when fuel, air, or electrical flow is disrupted. Moisture, thick oil, or clogged vents can cause shutdowns.
Barret Abramow of Grounded Electric advises checking oil, fuel freshness, and wiring before calling a professional.
Why Generators Start Then Shut Off
Generators that start but stop quickly often have oil, fuel, or sensor imbalances.
- Low oil or fuel supply
- Clogged carburetor
- Faulty spark plug or wiring
Generator Shuts Off After 20 Minutes
Overheating or blocked fuel flow can trigger automatic shutdowns.
Generator Runs for 30 Seconds Then Stops
A clogged carburetor or faulty low-oil switch may cause short cycling. In some cases, a Generac generator starts and then dies because of sensor errors or air-fuel imbalance, which requires quick inspection to avoid engine damage.
Diagnosing Generator Issues by Model Type
Portable generators often fail from dirty fuel, standby units from sensor issues, and RV models from vapor lock or filter blockages. These are among the most common generator problems that owners encounter, often requiring only minor part replacements or calibration.
Bobby Mulholland recommends logging symptoms and maintenance history to simplify diagnosis.
Fuel and Air Issues (Choke or Starting Fluid Problems)
Dirt or old fuel blocks carburetor jets and restricts airflow. If your generator starts but does not stay running, open the choke slightly and inspect the filters. Use a 10mm socket to clean the carburetor bowl or a multimeter to test the oil sensor safely.
Electrical Problems Under Load
A generator that shuts off under load may be overloaded or have a weak voltage regulator. Bobby Mulholland recommends testing loads gradually with a watt meter to prevent shutdowns.
Environmental Factors Affecting Performance
Humidity, dust, or freezing temperatures can reduce generator reliability. Keep the unit dry, ventilated, and run it monthly to circulate fuel.
How to Fix a Generator That Keeps Cutting Off
Troubleshooting Guide
- Check oil and fuel.
- Inspect the spark plug and wiring.
- Restart with the choke half open.
If that fails, reduce the load and test airflow before repeating the sequence.
When to Call a Licensed Electrician
If your generator won’t stay on, contact Grounded Electric. Barret Abramow and his team can diagnose deeper electrical faults safely.
Quick Parts Reference
- Carburetor kit – fixes stalling
- Oil switch – prevents false shutdowns
- Spark plug – ensures ignition
- Voltage regulator – stabilizes power
For those troubleshooting fuel supply issues, it helps to understand what a Generac generator runs off of to ensure proper maintenance and prevent stalling.
Preventive Maintenance and Long-Term Care
Change oil — Every 50 hrs — Prevents wear
Clean air filter — 3 months — Maintains airflow
Replace fuel filter — 6 months — Improves performance
Inspect spark plug — 100 hrs — Ensures ignition
Performing these steps and storing your generator in a dry space prevents shutdowns and extends its lifespan.
If your generator won’t stay running or shuts off unexpectedly, schedule an inspection with Grounded Electric today. Our team will restore your system’s performance and keep your power running when you need it most.
