Florida generator guide

What a Real Generator Service Includes vs a "$95 Oil Change"

Your standby generator kicks on once a week, runs a few minutes, shuts off. Sounds healthy. But that weekly run is the engine spinning with nothing plugged into it — like revving a car in the driveway to prove it can tow a loaded trailer. A quick $95 visit and a real service both end the same way: a clean machine and a signature on a slip. Only one of them made your house lose power on purpose, on a calm sunny day, to find out what actually happens.

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About five minutes. No salesman, no all-day window.

The weekly self-test is telling you a half-truth

That exercise cycle you hear every week is doing one job: keeping the engine limber so the fuel system doesn't gum up. Sitting still is what kills these units — a generator that never runs will varnish its own carburetor and refuse to start on the one night you need it. So the weekly run matters.

Here's the catch. During that run, the generator isn't powering anything. Your house stays on utility. The engine turns over, warms up, and quits, and the whole time it never feels the weight of your air handler, your well pump, your fridge all slamming on at once.

So "it ran fine Tuesday" tells you the engine starts. It doesn't tell you the machine can carry a Florida house through a July afternoon when the outage hits and every load comes on at the same moment. Those are two different questions, and the cheap visit only ever answers the easy one.

What actually gets touched — and what gets skipped

An oil change is an oil change: drain, new filter, new plugs if they're fouled, wipe down the enclosure, done. All of that is real work and all of it needs doing. The plugs, for what it's worth, usually come out of a kit already gapped for your model, so a good tech just verifies the gap rather than resetting it.

What gets skipped is everything that takes a meter instead of a wrench. The battery is the big one — most no-starts trace back to it — and the only way to know it's still strong is to test what it can push under a cold-crank load, not just read its resting voltage. A battery can show a healthy number sitting still and still collapse the instant the starter pulls on it.

Then there's the fuel side, which is where it gets strange. Your generator's entire appetite for gas gets checked against a column of water a few inches tall — that's literally the unit of measure, inches of water column. Too little pressure and the engine starves under load and stumbles right when the house leans on it. A wrench-and-wipe visit never puts a gauge on it. A real one does, plus the valve clearance and the firmware, because both Generac and Kohler push updates that change how the machine behaves and nobody drives out to install them for you.

The one test that can't be faked

Here's the part that separates a signature from a service. At some point the tech should walk to your transfer switch and cut you off from the grid on purpose — simulate the outage, right there in the driveway, sun shining.

Now the generator has to do the whole job for real: sense the power drop, start, take the entire house onto its own shoulders, hold it steady, and then hand it cleanly back to the utility when "power returns." That's a full-load transfer test, and it's the only moment anyone actually proves your backup plan works before you're betting your freezer and your bedroom AC on it.

Everything else is prep. This is the exam. And it's the exact step a quick visit leaves out, because it takes time, it takes knowing your automatic transfer switch, and it means deliberately making the lights go dark for a minute. Skip it and you've paid for a clean machine that has never once, under load, done the thing you bought it to do.

It starts before the service slip — with the right unit for your address

All of this assumes the generator sizing your house in the first place was matched to your house. A unit that's a hair too small for your square footage, your HVAC tonnage, and everything you want to keep running will fail that full-load test no matter how clean the oil is — it was set up to come up short.

That's the part GENERasic settles before anyone signs anything. Tell it your address and what you want kept alive when the grid drops, and it works out the sizing from your actual home, not a guess. What comes back isn't a range to decode or a "starting at" number that grows by install day. It's one committed installed price for your specific house.

So before you're stuck wondering whether the machine in your side yard can really carry the load, find out what carrying your load actually takes. Get your price for your address, and start from a number that's real.

Common questions

My generator won't crank — is it the battery?

Almost always, yes — a dead or weak battery is the number one reason a standby unit won't start. But "weak" is sneaky: the battery can read a normal voltage sitting still and still fold the second the starter pulls on it. The real check is a cold-crank load test, not just a voltage reading. Plan on replacing the battery every two to three years whether it looks fine or not, because in Florida heat it ages faster than the calendar suggests.

Do I really need the valve adjustment, and how often?

Yes, it's a real maintenance item, not an upsell. Valve clearance drifts as the engine runs, and out-of-spec valves make a unit harder to start and rougher under load. The typical interval is once a year or roughly every 300 run hours, whichever comes first. It's also one of the steps a quick oil-change visit tends to skip, since it takes more than a drain pan and a rag.

Do the spark plugs need the gap set, or are they good out of the box?

The plug kits sold for a specific generator model usually come pre-gapped from the factory, so most of the time you're verifying the gap, not setting it. Still worth checking with a gauge before they go in — a plug can get knocked out of spec in shipping. And replace them, don't just inspect, if they come out carbon-fouled or the ignition's gone weak.

Can I just do the service myself to save the fee?

You can absolutely do the oil, filter, and plugs yourself, and plenty of owners do. Where it gets hard is the stuff that needs instruments and know-how: a cold-crank battery test, a fuel-pressure check in inches of water column, firmware, and especially a full-load transfer test through your automatic transfer switch. That last one is the part that actually proves the machine will carry your house, and it's tough to do safely without the right gear and a second set of hands.

Generac says 5W-20 but I've seen 5W-30 used — which oil is right?

Go by your unit's owner's manual for your specific model and climate, not by what someone used on a different generator. Newer air-cooled models often call for a synthetic 5W blend, but the exact weight can vary by model and by whether the engine is past break-in. In a warm Florida climate the manual's hot-weather recommendation is the one to follow — when in doubt, match the book for your serial number.

Stop reading ranges. Get your number.

GENERasic pulls the real property, flood, and elevation data for your exact address and returns one all-in installed price — sized to your home, your fuel, and your flood elevation. The vetted local installer confirms it on site.

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