Why You Shouldn't Drive a Car With Low/No Coolant

Why You Shouldn't Drive a Car With Low/No Coolant

23rd Jan 2018

red GXP parked on a dirt road

Coolant Levels

When was the last time you checked your car's coolant levels? Most drivers rarely, if ever, check their coolant levels. It's not until a problem manifests when the driver opens the radiator and discovers it's missing coolant. Even if your car starts, however, you shouldn't drive it with low coolant levels for the following reasons.

What Is Coolant?

First, it's important to understand what coolant is and why it's important. Coolant, as the name suggests, is designed to cool the engine. It runs through the engine block and cylinder heads while picking up heat, after which it displaces this heat through the front of the car at the radiator.

Different cars use different types of coolant. Most, however, use a 50/50 mixture of distilled water and antifreeze. You can make your own coolant using the appropriate mixture (check your vehicle's manual), or you can purchase pre-made coolant from your local auto parts store.

Overheating Engine

The biggest concern of driving a car with low coolant levels is the potential for overheating the engine. If there's not enough coolant present, temperatures can rise to potentially catastrophic levels, increasing the risk for a blown head gasket, warped cylinder head or cracked engine block. When this type of damage occurs, it can cost thousands of dollars to repair.

Water Pump Failure

Driving a car with low coolant may also cause the water pump to fail. Without adequate coolant levels, the water pump loses its lubrication; thus, increasing the risk of failure. This compounds the problem of overheating, as a faulty water pump isn't able to move coolant through the engine and radiator.

Raises Boiling Point of Coolant

Another problem associated with low coolant levels is the simple fact that it raises the boiling point of coolant. Automotive cooling systems are designed to create a pressurized environment. When full, the pressurized system lowers the boiling point of coolant, making it more effective at cooling the engine. If your car has low coolant levels, however, the boiling point will be higher, which can cause your coolant to boil off.

Creates Hot Spots

Furthermore, low coolant levels create hot spots in the engine. Even if your car's temperature gauge shows normal engine temperature, certain areas of the engine may become hotter than other areas. This is because coolant can't reach the engine engine when there's low coolant levels. The end result is the presence of hot spots that can lead to blown head gaskets and other related engine damage.

low coolant graphic