Generator brands · Complete sets
Repairing and Servicing SDMO, Kohler-SDMO and Kohler Generators
For SDMO, Kohler-SDMO and Kohler generators anywhere in Gauteng, we do the repairs, servicing and maintenance on site. SDMO built its sets around engines from several makers, so the first step on any job is the engine data plate: it decides the oil, filters and many of the repairs. We also work on the controller, the alternator and the changeover, and on Kohler home standby units like the one pictured.
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
From SDMO to Kohler-SDMO to Kohler
SDMO began as a French generator set builder in Brest and became part of the American Kohler group in the mid-2000s. Later sets carry the Kohler-SDMO name and, on newer models, Kohler alone, but many SDMO-badged sets are still at work in offices, shops, farms and factories. Whatever the badge, the idea is the same: a set built around an engine from one of several makers, with an SDMO or Kohler controller and, often, a Leroy-Somer alternator.
The Kohler name also covers a very different machine: the compact home standby unit in the photo. Units like this run on LPG or natural gas, usually with an air-cooled engine, a controller built into the enclosure and a matching automatic transfer switch. They start themselves during load shedding and exercise on a timer. Their servicing is closer to other gas generators of the type; compare our Generac page.
Identify the engine first
| What you see | What it tells us |
|---|---|
| Set model on the nameplate | What it tells usThe rating and build. On many SDMO models the first letter hints at the engine maker, such as J for John Deere or V for Volvo Penta, but only the engine plate confirms it |
| Engine data plate | What it tells usMaker, model and serial number: John Deere, Volvo Penta, Mitsubishi, Doosan or another make. This sets the oil grade, filters and engine parts |
| Front of the controller | What it tells usNexys, Telys, Kerys or an APM panel on SDMO and Kohler-SDMO sets; sometimes a Deep Sea or ComAp module on a retrofitted set |
| Alternator plate | What it tells usOften Leroy-Somer, sometimes another make, with the regulator type needed for voltage faults |
| Service sticker and hour meter | What it tells usWhen the set was last serviced, and whether it is now due by hours or by time |
Controllers
SDMO and Kohler-SDMO control panels
Nexys
The simpler SDMO panel. It starts, stops and protects the set, with basic fault indication, and is common on manually started and smaller sets.
Telys: ATS and changeover problems
Adds metering, adjustable settings and automatic operation, so it is common on sets that work with an automatic changeover. Faults are shown as messages.
Kerys
Found on larger and paralleled sets, where it also handles synchronising and load sharing. A fault is checked across the whole power system, not one set.
APM panels: Control panel repairs
Later Kohler-SDMO sets moved to the APM range, which logs events and, on the larger models, can be monitored remotely. Settings must match the engine fitted.
Servicing
How an SDMO service is planned
- 01
Identify the engine
From the engine plate, so the oil grade, filters and belts match the engine maker’s schedule rather than a guess based on the set’s size.
- 02
Service the engine
Oil and filters, fuel filters and the water separator, coolant, the air filter and belts, at the interval the engine maker sets.
- 03
Service the set
Battery and charger, controller settings and alarm history, alternator connections, canopy seals and the base fuel tank.
- 04
Test the changeover
On automatic sets, a simulated mains failure checks start, transfer, return and cool-down, followed by a run under load where the site allows. A maintenance plan repeats these checks between services.
Service points
What to watch on SDMO and Kohler sets
Engine-specific weak points: John Deere engines
A John Deere, Volvo Penta or Mitsubishi engine each brings its own common faults, from injectors to water pumps. The engine maker’s page is the better guide.
Canopy corrosion
Steel canopies and base frames rust where paint is damaged and water lies. Hinges, locks and seals need attention on older sets.
Mains sensing and changeover: ATS and changeover problems
Automatic sets depend on sensing fuses, relays and contactors. A failure here looks like a generator fault but is not.
Alternator and regulator: AVR repairs
When voltage is wrong or missing, the regulator, rotating diodes and windings are tested in turn.
Kohler home standby: Standby generators
Gas-fuelled units need oil, the air filter, spark plugs and valve clearances seen to, and the transfer switch tested on a simulated outage.
Portable SDMO units: Portable and inverter generators
SDMO also made portable petrol generators, which need the carburettor, spark and pull-start care of any small petrol unit.
Independent service
We Service & Repair All Generator Brands
Onsite Generator Repairs is an independent generator specialist. We repair, service and maintain SDMO equipment as part of our work on every make of generator.
Manufacturer warranty claims go through the manufacturer’s own network. If your generator is still under warranty, check the warranty terms before arranging work by anyone else.
Brand names and trademarks belong to their respective owners. Onsite Generator Repairs is an independent service and repair company.
Service areas
Where we work in Gauteng
FAQ
Frequently asked questions
Is SDMO the same company as Kohler?
SDMO became part of Kohler, and its sets were branded Kohler-SDMO and later Kohler. Older SDMO-badged sets are still widely used, and we work on all of them.
Which oil and filters does my SDMO set need?
Those specified for the engine fitted, which varies by model. Send us a photo of the engine data plate and we will bring the right parts: genuine parts from the engine’s maker or quality equivalents made to the same specification, as stated on the quote.
Can a failed Nexys or Telys panel be repaired?
Sometimes. If not, it can be replaced with a modern controller, wired and configured for your engine, alternator and changeover. See control panel repairs.
Do you work on Kohler home standby generators?
Yes. We service and repair the engine, controller and transfer switch on Kohler home standby units. Work on the gas supply itself needs a registered gas practitioner. See residential generator services.
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- We Arrive Within 1–2 Hours (usually within 1 hour)
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