Updated
Guide · Outage readiness
Generator Not Used for Months? How to Get It Ready
A generator that has stood through a long spell without outages is not resting: its fuel, battery and seals have been ageing the whole time. This guide explains what changes in a standing generator, the safe checks you can do yourself, and what a recommissioning visit covers, so the set works on the day the power goes.
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- Fuel, battery and start checked
- Run on your real load
- Written quote first
- Onsite across Gauteng
What standing does
What happens to a generator that stands for months
Petrol goes stale. Left in the tank and the carburettor, it thickens and leaves a varnish that blocks the small jets, which is why a petrol set that ran perfectly before storage will not start or runs only on choke.
Diesel takes on water. Air breathing in and out of a part-full tank leaves condensation behind, and water in diesel feeds the microbial growth known as diesel bug, which blocks filters. A standby set can start, take the load and then die as the filter clogs.
Batteries discharge, even when nothing is connected, and a battery left flat for long enough may not recover. On a standby set, a battery charger that has failed quietly leaves the generator unable to crank when the mains drops.
Other things age too: coolant, rubber hoses and seals, and the controller, which may already be holding an alarm from the last run. Rodents nest in quiet canopies and chew wiring. None of this shows until the set is asked to work, which is the worst moment to find out.
Safe checks for owners
What you can check yourself, with the generator off
Do these with the engine stopped and cool. Leave the distribution board, the changeover and anything inside the control panel to us.
Look around the set
Look for leaves, nests, chewed wires, fuel or oil stains under the set, and blocked vents on a canopy.
Oil level
Check the dipstick on level ground. Low oil, or oil that looks milky, is a reason not to start it and to call us.
Fuel age and level
Petrol that has stood for months is suspect. On a diesel, note how full the tank is and when it was last filled.
Battery terminals
Look for corrosion or loose terminals on electric-start and standby sets. A white or green crust means it needs attention.
The controller screen
Photograph any alarm or warning on the controller and send it to us before anyone resets it.
Where it will run
Make sure a portable set will run outdoors, away from doors and windows, and that its leads are in good condition.
Recommissioning visit
What we do to get a standing generator ready
The order matters: starting an engine on old fuel, low oil or a weak battery can turn a small job into a repair.
01
Inspect before starting
We check oil, coolant where fitted, belts, hoses, wiring and the area around the set before we try to start it.
02
Fuel
Stale petrol is drained and the carburettor cleaned. Diesel is checked for water and contamination, and filters are changed if they need it.
03
Battery and charger
The battery is load tested and the charger checked, so the set can crank when the mains fails and not only today.
04
Controller and alarms
Stored alarms are read and their causes traced, and automatic start is set back to Auto where it belongs.
05
Start and run on load
The set is started and run on your real load, and a standby set is tested with a real mains failure and return.
06
Report and quote
You are told what was found and what is due. Any repair beyond the visit is quoted in writing first.
Common faults after months of standing
What a standing generator usually does on its first run, the likely cause, and where to read more.
| What happens | Likely cause | Read more |
|---|---|---|
| Petrol set will not start, or runs only on choke | Stale petrol and varnish in the carburettor | Generator not starting |
| Clicks or cranks slowly | Flat battery, corroded terminals or a failed charger | Battery not charging |
| Starts, takes the load, then dies | Water or diesel bug blocking the filter | Contaminated diesel |
| Standby set stayed off in the outage | Controller left in Stop or Manual, or a stored alarm | Not auto starting |
| Runs, but no power reaches the house | Tripped breaker, changeover position or a voltage fault | Not producing power |
| Smoke on the first start | Oil or fuel that settled while standing, or a deeper fault | White smoke |
Typical prices: carburettor cleaning or rebuild R900 to R2,200, battery replacement R900 to R2,800, fuel system cleaning and polishing R1,500 to R3,500. See every range on the generator repair cost guide.
Common Questions
Questions about generators that have stood for months
Can I just start a generator that has not run for months?
Check the oil and look around the set first. On a petrol set, old fuel is the usual problem, and repeated pulls on a stale carburettor wear the recoil and flood the engine. If it does not start easily, stop and call us rather than flattening the battery.
Should I drain the petrol before storing a generator?
Follow your owner’s manual. Many manuals advise running the carburettor dry or draining it, or using a fuel stabiliser, before long storage. Petrol left in the carburettor for months is a common reason a stored set will not start.
How often should a standby generator run when there are no outages?
Follow the manual for your set. Many standby generators run a regular automatic exercise, and a periodic run on load is better than none at all. We can check whether the exercise function on your controller is set and working.
Does diesel go off?
Diesel lasts longer than petrol, but it takes on water from condensation, and water feeds microbial growth that blocks filters. A tank that has stood part-full for months is worth checking before you rely on it.
What does a recommissioning visit cost?
It depends on what the set needs. You pay the callout, which is waived if you accept our quote, and every repair beyond the checks is quoted in writing before we start.
My generator failed in the first outage after months. How fast can you come?
We are open 24/7 and arrive within 1 hour for a breakdown. Tell us what the set did and send a photo of any alarm.
Still unsure what the fault is? Call or WhatsApp 082 057 4605 for onsite diagnosis.
Related Pages
Fuel, batteries and servicing
- Generator Servicing A full service before the next outage
- Contaminated Diesel Water, diesel bug and dirt
- Battery Not Charging Charger and battery faults
- Generator Not Starting No crank, click or no fire
- Service Checklist What a service covers
- Generator Maintenance Readiness checks on a schedule
- Standby Generator Maintenance Keep an automatic set ready between outages
- Petrol Servicing & Maintenance An ongoing routine for small petrol sets
Service Areas
Onsite visits across Gauteng
We come to your generator anywhere in Gauteng, 24/7. Choose your region for local suburbs, call-out details and the faults we see most there.
What to send before we attend
These details help us plan the visit and bring the right parts. Send what you can on WhatsApp; if you can’t find the model number, we still book the visit.
- Location
- The suburb or site, so the visit can be booked in the right area.
- Make and model
- The generator brand and model, if they are known.
- kVA
- The size printed on the data plate.
- Fuel type
- Diesel, petrol, LPG, natural gas, or dual-fuel.
- Controller model
- The module name on the panel, when it is visible.
- Fault or alarm
- What the set does, and any text on the screen.
- Photos
- The generator, the data plate, and the controller or alarm. Send these on WhatsApp.
Book a Visit
Book a readiness check
Tell us your suburb, the generator make and fuel, and roughly how long it has stood. Send a photo of any alarm on the controller.
- Call
- 082 057 4605
- Message us on WhatsApp
What happens next
- We reply with questions about the generator, or to book a visit.
- A technician comes to you. For a breakdown we arrive within 1 hour.
- The fault is diagnosed on site and you get a written quote. No work starts until you accept it.
Charlie, lead technician: Degree in Mechanical Engineering, Degree in Electrical Engineering, Diesel Plant Fitter. Generator specialists since 2000.