AMSOIL Engine Fogging Oil
AMSOIL Engine Fogging Oil (FOG) is an aerosol-applied corrosion preventive for the upper end of two- and four-stroke engines that sit unused for long stretches. Sprayed into the air intake, carburetor, or cylinder through the spark plug hole, the formula leaves a clinging oil film on cylinder walls, piston rings, valves, and other steel and iron surfaces so that condensate cannot reach bare metal during storage.
Long-term film retention against storage corrosion
Seasonal equipment that sits through summer heat or winter cold cycles repeatedly through ambient temperature swings, and water vapor inside the crankcase and combustion chamber can condense on cool steel and iron surfaces. That condensate forms surface rust on cylinder liners, piston rings, anti-friction bearings, and the steel and iron contact surfaces of rotational seals. Engine Fogging Oil delivers superior film retention compared with the residual film left behind by ordinary motor oil, so the protective barrier stays in place after the engine is shut down for the season.
The aerosol spray pattern reaches deep into combustion chambers and carries the oil to surfaces that gravity would not coat on its own. That distribution is especially useful for outboard motors and other horizontal cylinder layouts, where a poured oil simply runs to the low side of the bore and leaves the upper cylinder wall unprotected.
Dry-start protection at season startup
Long storage also dries out cylinders, and a dry-start at the beginning of the next season often results in permanent damage to cylinder walls and piston rings. Pre-storage fogging keeps an oil film on cylinder liners, piston rings, and the surrounding steel and iron surfaces, so the first crank of the new season begins with lubrication already present on the bore.
Two-stroke and four-stroke compatibility
The aerosol formulation is designed for both two- and four-stroke engines, including hand-held power equipment, recreational vehicles, marine, agricultural, and construction engines. Most two- and four-stroke motor oils are formulated to cling to engine component surfaces and act as a temporary barrier against condensate, but that residual film weakens with time. Engine Fogging Oil is built to hold its film through the entire storage interval rather than thin out after a few weeks of inactivity.
Aerosol delivery for clean, complete coverage
The spray can format keeps application clean and repeatable. The straw delivers the oil through the spark plug opening, intake throat, or carburetor, and the propellant atomizes the fluid so it coats more internal area than a poured or syringe-applied oil can reach. Application directions vary by engine layout, so the equipment owner's manual is the final word on intake routing and run-time during fogging. The AMSOIL vehicle lookup guide helps confirm the right pre-storage routine for a specific powersports machine, outboard, or small engine.
Pairs with a full pre-storage fluid plan
Fogging the upper end is one step in a full pre-storage service. Fresh oil and a new filter at the same service give the bottom end of the engine clean lubricant to sit in, while Engine Fogging Oil takes care of the cylinders, rings, and other upper-end surfaces. Pre-storage fuel handling for ethanol-blended gasoline is its own step in the plan, and the AMSOIL Quickshot guide walks through where that product fits alongside fogging in a complete winterization plan.
Recommended applications and service intervals
Engine Fogging Oil is positioned as a pre-storage corrosion preventive any time a two- or four-stroke engine will sit unused long enough for condensate to form inside the engine. Application timing follows the equipment storage cycle rather than a mileage interval. Listed applications include, but are not limited to, motorcycles, snowmobiles, ATVs, outboard motors, stern drive and inboard marine engines, personal watercraft, lawn equipment, chainsaws, snowblowers, portable generators, hand-held power equipment, motor scooters, powered farm equipment, powered construction equipment, cars, and trucks.
- Seasonal storage of outboard motors, sterndrives, and inboard marine engines, including PWC, before the boat is laid up for the off-season.
- Snowmobile summer storage and motorcycle, ATV, or UTV winter storage where the machine will sit for months.
- Lawn tractors, chainsaws, snowblowers, generators, hand-held power equipment, and powered farm or construction equipment that runs seasonally and then sits.
- Not available in Canada. Outside US distribution is handled by local AMSOIL channels rather than this dealer site.
Engine Fogging Oil is a topical corrosion preventive for the upper end and is not a substitute for the engine oil, gear lube, or fuel stabilizer that a full pre-storage service requires. Pair it with a fresh oil and filter change, fuel stabilizer in the tank, and any chassis grease points called out by the equipment manufacturer. Aftermarket engine additives are not required and should not be mixed into the can or sprayed into the same intake event.
Order AMSOIL Engine Fogging Oil
Engine Fogging Oil ships in a 12 oz. spray can (product code FOGSC-EA) and a case of twelve 12 oz. cans (product code FOGSC-CA) for fleets, marinas, small engine shops, and customers winterizing several machines at once. AMSOIL products are backed by the AMSOIL Limited Liability Warranty. Use the AMSOIL vehicle lookup guide to confirm matching engine oil and filter recommendations for the same machine, and the AMSOIL Quickshot guide for ethanol-fuel storage protection that pairs with fogging. Order Now
Customer reviews
Does the trick
Works good for all small engines and winterizing.
By Jim from Effingham, illinois on November 07, 2025.
Would recommend this to a friend.
Great quality
I use this for winterizing my boat motor every year. Works great, would recommend it.
By Robert from Colorado on July 22, 2025.
Would recommend this to a friend.
Easy to use
Generator was easier to start and ran great.
By Harvey from Houston, Texas on January 04, 2024.
Would recommend this to a friend.
Read all 14 reviews
Frequently asked questions
What is Engine Fogging Oil and what does it do?
Engine Fogging Oil is an aerosol-applied corrosion preventive sprayed into the upper end of an engine before storage. It coats cylinder walls, piston rings, valves, and other steel and iron surfaces with a clinging film that prevents condensate from reaching bare metal and forming surface rust during periods of inactivity, and it keeps a lubricating film in place to protect against dry starts when the engine is brought back into service.
How is Engine Fogging Oil applied to a typical engine?
Application varies by equipment, so the engine manufacturer's procedure is the controlling document. The general pattern is to bring the engine to operating temperature, then spray Engine Fogging Oil into the air intake or carburetor, or remove the spark plug and spray directly into the cylinder, while the engine runs at idle until shutdown. Replacing the spark plug after fogging seals the cylinder until the next start. Always follow the equipment owner's manual for routing, run time, and any fuel-system steps.
Can Engine Fogging Oil be used on outboards and other marine engines?
Yes. Outboard motors, stern drive engines, inboard marine engines, and personal watercraft are listed applications. The aerosol formulation is especially useful on outboard motors because the horizontal cylinder layout leaves the upper bore unprotected when oil is poured rather than sprayed, and the atomized spray distributes oil evenly around the cylinder wall regardless of orientation.
Does Engine Fogging Oil work on two-stroke engines as well as four-stroke?
Yes. The product is positioned for both two- and four-stroke engines, covering hand-held power equipment, snowmobiles, motorcycles, ATVs, lawn and garden equipment, generators, and the cars and trucks listed in the application set. The same can suits a chainsaw cylinder and a four-stroke outboard cylinder when applied per the relevant manufacturer's directions.
Is fogging an engine necessary for short off-season storage?
The product is intended for engines that will sit long enough for condensate to form inside the engine, which depends on storage temperature swings and humidity rather than a fixed number of weeks. Equipment stored across a full off-season, such as a boat over winter or a snowmobile over summer, is the primary use case. Equipment used regularly throughout the year typically does not need fogging.
Where should the can be stored, and how is the empty can disposed of?
The aerosol can should be kept away from heat and ignition sources per the can label. Local rules for aerosol disposal often differ from rules for other waste, so the empty container should be disposed of in accordance with all federal, state or provincial, and local regulations. Recycling programs that accept pressurized containers are the preferred route where available.
Will using Engine Fogging Oil affect the AMSOIL warranty?
AMSOIL Engine Fogging Oil is backed by the AMSOIL Limited Liability Warranty when used as directed for pre-storage protection of the engines listed in the application set. Application directions in the equipment owner's manual still control how the engine is fogged and brought back into service.
