No, you cannot safely drive a car for more than a very short distance without an alternator belt. The vehicle might start and run for a short while, but you risk severe engine damage from overheating and a complete electrical failure that will leave you stranded. The alternator belt, often called the serpentine belt, is a critical component that powers multiple systems simultaneously. It spins the alternator, which charges the battery and powers all the electrical components while the engine is running. More critically, in most modern cars, this same belt also drives the water pump, which circulates coolant to prevent the engine from overheating.
Once the belt breaks, the battery begins to power everything on its own. You'll notice the battery warning light illuminate on your dashboard almost immediately. Depending on the charge level of your battery and what electrical accessories you're using (like headlights or the AC), the car will likely only run for 20-60 minutes before the battery is completely drained and the engine stalls. However, the more imminent danger is engine overheating. Without the water pump circulating coolant, the engine temperature will skyrocket within minutes, potentially leading to a catastrophic engine failure such as a warped cylinder head or a blown head gasket—repairs that can cost thousands of dollars.
If the belt breaks while you're driving, the safest action is to pull over and turn off the engine immediately. The only scenario where driving without a belt is marginally acceptable is if you are literally a few blocks from a repair shop and you can drive there without any electrical load (no AC, blower, or radio) and while closely monitoring the temperature gauge. Even then, it's a significant risk. The best practice is to call for a tow truck to avoid causing much more expensive damage.
