Gas Fill Cap
Always use gasoline at the octane recommended by your snowmobile's manufacturer. Avoid using old, stale gasoline since it can cause engines to perform poorly or malfunction. Also beware that most alcohol and ethanol blends can cause engine damage; unless you're absolutely certain your engine will operate safely with ethanol, it is best to use straight versus blended gasoline.
Always make sure your gas tank is full before starting any outing to ensure you're prepared for unexpected delays or situations where you'll consume more fuel than anticipated.
Some snowmobile models have carriers which can be used to carry a spare gas can. Always ensure the gas can is closed tightly to prevent spillage and is securely fastened to the carrier.
Two-stroke snowmobiles have an injector oil reservoir since they require oil to be injected as a lubricant into the snowmobile engine. If your machine runs out of injector oil, your engine will seize and require expensive repairs. Always check the injector oil reservoir level before you start your machine, whenever you refuel, and again at the end of every ride. Follow the owner's manual recommendations on the type of oil to use and the proper level to maintain in the oil reservoir.
Four-stroke snowmobiles do not have an injector oil reservoir. Instead, monitor the oil pressure gauge to ensure the engine has sufficient oil in the crankcase, and by periodically checking the oil level on the engine's dipstick (similar to checking oil in a car's engine).
Antifreeze is needed to cool most snowmobile engines when they are running. Check the antifreeze reservoir regularly and follow the manufacturer's directions in your owner's manual for the type of antifreeze required and the proper level to maintain in your reservoir.