About us
Independent Generator Specialists Working On Site in Gauteng
Onsite Generator Repairs is an independent generator specialist: we repair, service and maintain generators where they are installed, anywhere in Gauteng, 24/7. We Service & Repair All Generator Brands, from small portable units to industrial standby sets, and we have been doing this work since 2006.



Established 2006
20 years of experience
24/7 operations
We Arrive Within 1–2 Hours
(usually within 1 hour)
Free callouts and quotations
One-year warranty
Qualified and certified technicians
We Service & Repair All Generator Brands
All generator makes and models
1 kVA–20,000 kVA capability
The business
Who we are
Onsite Generator Repairs is a generator repair, servicing and maintenance business in Gauteng, South Africa. We are a service-area business: our technicians travel to homes, estates, shops, offices, factories and plant rooms across the province, and the repair or service happens where the generator stands.
There is no counter or showroom to visit, so every job starts with a call, a WhatsApp message, an email or the enquiry form. The name says how we work. Most generator faults can be found and fixed on site, and a standby set that is bolted to a plinth and wired into a changeover panel is not something anyone wants to move.
Working on site has another advantage: we test the repair on your own load and through your own changeover, which is how the generator has to perform during the next outage.
- Business
- Onsite Generator Repairs
- What we do
- Generator repairs, servicing and maintenance, done on site
- Service area
- All of Gauteng: Johannesburg, Pretoria and Centurion, Ekurhuleni, the West Rand and the Vaal Triangle (service areas)
- Phone
- 076 434 7292
- Message us on WhatsApp
Independent
Why an independent specialist helps you
A generator set is built from parts made by different companies. The engine may be a Perkins, Cummins or Volvo Penta; the alternator a Stamford, Leroy-Somer or Mecc Alte; the controller a Deep Sea, ComAp or SmartGen. The changeover panel is often built by whoever installed the set, and the name on the canopy is usually the company that assembled the whole package.
Faults do not respect those boundaries. A set that starts but will not take the load might have an AVR fault in the alternator, a fault in the controller’s transfer signal or a burnt contactor in the changeover. We Service & Repair All Generator Brands. That means one technician follows the fault from the engine through the alternator and controller to the changeover, whatever the make of each part. You are not passed between specialists who each check only their own component.
Independence also helps on sites with more than one generator. An estate, business park or factory may have sets of different makes and ages, bought over many years, and one service programme can cover them all. Older and less common makes get the same attention as current models, as long as parts can still be found.
- Engine: fuel system, governor, cooling, starting and lubrication
- Alternator: AVR, exciter, rotating diodes and windings
- Controls: controllers and control panels, sensors and alarms
- Changeover: ATS panels, contactors and mains sensing

How we work
What happens when you call us
- 01
Tell us what it is doing
Call or WhatsApp 076 434 7292, or use the contact form. The make, model, kVA rating, hour-meter reading and a photo of the controller screen help the technician arrive prepared.
- 02
A technician comes to site
We arrive within 1–2 hours, usually within 1 hour, at any hour of the day or night.
- 03
Diagnosis and a quotation
Free callouts and quotations. We show you what we found and quote before work starts, and what affects the cost is explained up front. Where repair or replacement are both options, we explain the trade-offs.
- 04
The repair or service
Most work is completed on site. If a part has to be replaced, ordered or taken away for bench repair, the quotation says so before you approve it.
- 05
Tested, then handed back
We run the generator after the work, under load where the site allows, and check the changeover where there is one. Our work carries a one-year warranty.
Services
From breakdowns to planned maintenance
Our work falls into three parts. Generator repairs find and fix faults, including emergency callouts when a set fails during an outage. Generator servicing replaces oil, filters and fluids at the intervals in the manufacturer’s schedule and checks the rest of the set while we are there. Generator maintenance turns those services into a programme of inspections and test runs, so the generator is ready all year.
Load shedding changed what generator care involves in Gauteng. Standby sets that once ran little more than their routine test runs had to carry the load through back-to-back outages, and long municipal outages still do the same. More starts and more running hours wear out batteries, changeover contactors and oil sooner, and the hour meter, not the calendar, often decides when the next service is due.
Specialist services
Around the core work
- AVR repairsVoltage faults traced to the regulator, the exciter or the sensing wiring.
- Control panel repairsBlank screens, false alarms, auto-start and mains-sensing faults.
- Fuel system repairsWater in the diesel, blocked filters, air leaks, lift pumps and injectors.
- Generator rewindingWindings tested on site, and a rewind arranged and quoted when one is needed.
- Load bank testingA stepped test under load that shows the set will hold up when it is needed.
- Generator installationSizing, siting, changeover and commissioning for a new or replacement set.

What we work on
From a portable petrol unit to a plant-room standby set
The range runs from small portable units to large industrial sets: 1 kVA–20,000 kVA capability.
A portable petrol generator and an industrial diesel set share little beyond the name. The first needs a clean carburettor, fresh fuel and a sound inverter module or AVR. The second adds turbochargers, liquid cooling, an automatic controller, a changeover panel and bulk fuel storage, and often an electronic governor.
Covering both ends means matching the work to the machine: the right checks, the right parts and the right test for the generator in front of us. The photo gallery shows the range, from garden plinths and side passages to basement plant rooms.
- Diesel generators, from silent home sets to prime-power plant
- Petrol generators and portable and inverter units
- Gas generators, including home standby units
- Standby generators with automatic changeover
Customers
Who we work for
Households and residential estates: Residential generator services
Home standby sets that keep lights, gates, alarms, borehole pumps and fridges going through outages, and the portable units many households rely on.
Shops, offices and clinics: Commercial generator services
Sets that protect trading hours, cold-room stock, IT and patient care, kept ready to start the moment the power goes.
Factories, warehouses and plant: Industrial generator services
Large standby and prime-power diesel sets, where testing under load and a planned maintenance programme matter most.
Brands
We Service & Repair All Generator Brands
All generator makes and models, from portable petrol units to large standby sets. 1 kVA–20,000 kVA capability.
- Cummins
- Caterpillar
- Perkins
- FG Wilson
- SDMO
- Volvo Penta
- MTU
- Deutz
- Doosan
- John Deere
- Kubota
- Yanmar
- Atlas Copco
- Himoinsa
- Pramac
- Lutian
- Generac
- Honda
- Yamaha
- Ryobi
- Kipor
- Mac Afric
- Stamford
- Leroy-Somer
- Mecc Alte
- Deep Sea Electronics
- ComAp
- SmartGen
Brand names and trademarks belong to their respective owners. Onsite Generator Repairs is an independent service and repair company.
All generator brandsService areas
Where we work in Gauteng
About us
Questions about us
Where are you based?
We are a service-area business covering all of Gauteng. Our technicians travel to your home or site, so the address that matters is where your generator is installed. See our service areas or call 076 434 7292.
How long have you been working on generators?
Onsite Generator Repairs was established in 2006, and we bring 20 years of experience to every job, from small portable units to large standby sets.
Do you only work on certain makes?
No. We are an independent generator specialist. We Service & Repair All Generator Brands, including the engines, alternators and controllers inside them. The brands page lists the makes we see most often.
Who will work on my generator?
Qualified and certified technicians. The technician who finds the fault explains what was found and talks you through the quotation before any work starts.
Can you look after every generator on our site?
Yes. Estates, business parks and factories often run several sets of different makes and ages. They can all go on one maintenance programme, with service dates set by the running hours and calendar of each set.
Talk to an independent generator technician
- 24/7 operations
- We Arrive Within 1–2 Hours (usually within 1 hour)
- Free callouts and quotations
