Table of Contents

1. What Happens When You Try to Start the Generator?
2. Check the Simple Things First
3. Has the Generator Been Standing With Old Fuel?
4. Can Low Oil Stop a Generator From Starting?
5. Is the Starting Battery Too Weak?
6. What If the Generator Cranks but Will Not Start?
7. Why Does a Generator Start and Then Stop?
8. What If the Generator Runs but Produces No Power?
9. When Should You Stop Troubleshooting?
10. How URIS Power Handles Generator Repairs
11. How Can You Reduce the Chance of This Happening Again?
12. Frequently Asked Questions
13. Get Your Generator Assessed Before You Need It Again

 

What Happens When You Try to Start the Generator?

Start by paying attention to what the generator actually does.

Different symptoms can point towards different areas of the machine.

What happens	Where the problem may be
Nothing happens	Switch, battery or starting system
It clicks but does not crank	Battery or starter system
It cranks but does not start	Fuel, choke, ignition or a protection system
It starts and then stops	Fuel supply, oil protection or another running fault
The engine runs but there is no power	Electrical output rather than an engine-starting problem

These symptoms help narrow the problem, but they do not identify a failed component on their own.

 

Check the Simple Things First

Before assuming something has failed, check the basic starting conditions specified for your generator.

For a typical petrol generator, that may include:

• Enough suitable fuel in the tank
• The engine switch in the correct position
• The fuel valve open, where fitted
• The choke set correctly for starting
• The correct engine oil level
• A charged starting battery on electric-start models
• Any warning lights or fault indicators

Starting procedures differ between models, so follow the owner’s manual rather than assuming every generator works in exactly the same way.

Safety matters too. Run portable petrol generators outdoors, away from enclosed spaces, because engine exhaust contains carbon monoxide. Never refuel a generator while the engine is running or still hot.

 

Has the Generator Been Standing With Old Fuel?

Fuel becomes particularly important when a backup generator spends long periods unused.

Petrol can deteriorate during storage. Contamination and deposits can also affect the fuel system, which may make an engine difficult or impossible to start.

Possible signs of a fuel-related problem include:

• Difficult starting
• Cranking without firing
• Rough running
• Starting and then stopping
• Poor performance after the generator has been stored

If the generator has been standing for a long time, check the manufacturer’s recommendations for stored fuel and use the correct fresh fuel where appropriate.

 

Can Low Oil Stop a Generator From Starting?

Yes, on generators fitted with a low-oil protection system.

Manufacturers use these systems to protect the engine from damage when there is insufficient oil. Depending on the generator, low oil can prevent normal operation or cause the engine to stop.

That can create a confusing situation where:

• The generator has fuel
• The starting controls appear correct
• The engine still refuses to run

Check the oil according to your generator’s owner’s manual. The machine may need to stand on a level surface for an accurate reading.

 

Is the Starting Battery Too Weak?

Electric-start generators introduce another possible problem: the battery.

A weak or discharged battery may cause:

• Slow cranking
• Clicking when you try to start
• The starter motor failing to turn
• Intermittent starting problems

A battery can sometimes still power lights or indicators while lacking enough capacity to operate the starter properly.

 

What If the Generator Cranks but Will Not Start?

If the engine turns over normally but never starts, you have already narrowed the problem.

Possible areas include:

• Fuel delivery
• Incorrect choke operation
• Old or contaminated fuel
• Spark plug or ignition problems
• Restricted air or fuel flow
• Low-oil protection
• Other engine or control faults

This is also where basic owner troubleshooting should start giving way to diagnosis.

 

Why Does a Generator Start and Then Stop?

A generator that starts successfully and then shuts down has a different problem from one that never fires.

Possible causes can include:

• Insufficient oil or a protection-system shutdown
• Restricted fuel supply
• Poor fuel quality
• Incorrect choke operation after starting
• Sensor or control faults
• Other engine problems

More advanced standby generators can also shut down when their control systems detect abnormal operating conditions.

 

What If the Generator Runs but Produces No Power?

If the engine starts and runs normally but connected equipment receives no power, you are no longer dealing with a starting problem.

The fault could involve:

• An overload or tripped breaker
• The alternator or inverter system
• Wiring
• Output components
• Controls or protection systems

Start with the basic breaker and overload checks described in the generator’s manual.

 

When Should You Stop Troubleshooting?

Basic checks are useful. They can eliminate simple operating problems before you book a repair.

Stop troubleshooting and arrange an assessment if:

• The generator still will not start after the basic checks
• It repeatedly starts and stops
• Fuel is leaking
• You hear unusual mechanical noises
• You see damaged wiring or electrical components
• A warning or fault indicator persists
• The starter system will not operate
• The engine runs but produces no power
• Finding the fault requires opening the fuel, ignition or electrical systems

Replacing parts without knowing the cause can increase the repair cost without solving the original problem.

 

How URIS Power Handles Generator Repairs

URIS Power has a fully equipped workshop that services and repairs generators along with other power equipment. Our workshop includes electric, four-stroke and two-stroke mechanics and handles equipment from most manufacturers.

The repair process is straightforward:

1. We log the generator and allocate a job number.
2. The applicable strip-and-quote fee is paid.
3. Our workshop assesses the machine and prepares a repair quote.
4. Repairs proceed once you approve the quote.
5. We clean and quality check the machine before collection.

 

How Can You Reduce the Chance of This Happening Again?

A generator that only comes out during a power outage still needs maintenance between uses.

Follow the service schedule for your model and pay particular attention to:

• Engine oil
• Fuel condition
• Starting battery condition
• Air filters and other routine service items
• Manufacturer storage recommendations
• Periodic operating checks

Do not wait for the next outage to discover that the generator has developed a starting problem.

If the machine becomes increasingly difficult to start, runs unevenly or shows warning indicators, servicing it before it fails completely can prevent a more inconvenient breakdown.

 

Frequently Asked Questions

Why does my generator crank but not start?

If the engine cranks normally but does not start, possible causes include fuel delivery, stale fuel, incorrect choke operation, ignition problems, low-oil protection or another engine fault. Check the basic operating conditions first. If they are correct, the generator needs further diagnosis.

Can low oil stop a generator from starting?

Yes, if the generator has a low-oil protection system. These systems protect the engine by stopping or preventing normal operation when the oil level falls too low. Check the oil level according to the manufacturer’s instructions before assuming another component has failed.

Why won’t my generator start after sitting for a long time?

Old fuel is one possibility. An electric-start battery may also discharge during storage, while maintenance issues can become apparent when the generator is used again. Start by checking fuel condition, oil level, battery condition where applicable and the correct starting procedure.

Why does my generator start and then shut off?

Low oil, restricted fuel flow, poor fuel quality, protection systems and other engine or control faults can cause a generator to start and then stop. Check for warning indicators and the basic fuel and oil conditions before arranging further diagnosis.

Where can I get a generator repaired in Johannesburg?

URIS Power services and repairs generators through our fully equipped Randburg workshop. We work on equipment from most manufacturers, assess the machine before repair and provide a quote before work proceeds.

 

Get Your Generator Assessed Before You Need It Again

URIS Power has supplied and serviced power equipment for more than 45 years, and our workshop handles hundreds of repairs each month. We can assess your generator, quote before carrying out repairs and assist with spare parts where available.

If repairing the machine no longer makes financial sense, we can also help you consider a suitable replacement.

Contact URIS Power or bring your generator to our Randburg workshop to have the fault assessed before the next time you need backup power.