Fuel stabilizer
STA-BIL Storage Fuel Stabilizer for Generators, 16 oz
A gasoline stabilizer added to fresh fuel, so the generator's tank and the cans beside it still start the engine when the outage comes — stale fuel being the most common reason a portable generator won't.
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Best for
Gasoline generators and stored fuel cans that sit for months between outages
Specifications
| Treat ratio | 1 oz per 2.5 gal of gasoline — this 16 oz bottle treats 40 gal |
|---|---|
| Storage claim | Keeps gasoline fresh up to 24 months (manufacturer's claim) |
| Fuels | Ethanol and non-ethanol gasoline, including gas/oil 2-stroke mixes |
| Directions | Fresh fuel only; run the engine 5 minutes to carry treated fuel through the system |
| Bottle shelf life | 2 years after opening, tightly capped |
Specifications as published by STA-BIL. Confirm against the current spec sheet before buying — manufacturers revise models without renaming them.
What's good
- Targets the gum and varnish from stale gasoline that block a small-engine carburetor
- One bottle treats 40 gallons — eight 5-gallon cans
- Works in the ethanol-blended gasoline sold at most US pumps
What's not
- Won't rescue fuel that has already gone stale — STA-BIL says it does not restore or improve old gasoline
- STA-BIL's own FAQ says gasoline stored over 12 months tends to lose volatility whatever is added — rotate cans every 6-12 months anyway
- Gasoline only; a propane or natural-gas generator needs none of this
Our verdict
Our no-start and surging troubleshooting keeps landing on the same cause: gasoline that sat in the carburetor long enough to varnish. Stabilizer is half of the fix and rotation is the other half. Treat each can when you fill it, run the generator five minutes so treated fuel reaches the carburetor, and still pour stored fuel into the car every 6-12 months — 24 months is the manufacturer's upper bound, not a schedule.
Compare with the alternatives
- Kidde COBD10 Carbon Monoxide Alarm — every level of the home and outside sleeping areas, before generator season
- Kidde 30CUD10-V Smoke + CO Alarm — hallways outside bedrooms, where a smoke alarm and a co alarm are both needed
- Southwire 12/3 SJTW 50 ft Outdoor Extension Cord (2588SW0002) — running a fridge, freezer or space heater from a portable generator at a safe distance
- Reliance Controls Pro/Tran 10-Circuit Transfer Switch Kit (31410CRK / 310CRK) — portable generators up to 7,500 running watts with an l14-30 outlet
- Reliance Controls PB30 Power Inlet Box (30 A, L14-30) — interlock-kit and transfer-switch installs fed by a portable generator's l14-30 outlet
- WEN PC3025 30-Amp Generator Power Cord, 25 ft (L14-30P to L14-30R) — connecting an l14-30 generator to a house inlet from 20 feet or more away
- Southwire Surge Guard Generator Neutral-Ground Bonding Plug (44400) — a floating-neutral generator run on cords, when an rv surge protector reports open ground or an ev charger refuses to start