How Much Coolant Loss Is Normal: Mechanics Guide

Many people believe that only gas and engine oil are the only fluids that keep a car running, but most of them don't know that coolant is an equally important fluid. Cars operate through a combustion mechanism that goes on in the engine. This and many other factors increase the temperature of the vehicle, which might include:

  • Kinetics of different wheels, chains, and gear sets
  • Electricity production and consumption
  • Air conditioning and more

Manufacturers keep devising different ways and techniques to keep the car's temperature to an optimum low. These techniques help in maintaining the external temperature of the vehicle. However, whatever is inside is dealt with by the coolant.

Coolant is like a car's thermostat because, contrary to what the name suggests, it doesn't only cool the vehicle. It senses the outside temperature and increases or decreases a car's temperature to keep it at optimum levels to avoid situations like overheating or overcooling, which may both lead to an unfunctional car.

So, if there's no coolant, the car is good for nothing. And one may wonder how much coolant is required for the proper functioning of the vehicle and what to do if its levels drop from the necessary amount? And even before that, what is the reason for coolant leakage?

Why Is There a Coolant Loss?

Low coolant can lead to an overheated car that may result in engine damage and leave one short of several hundred dollars for repairs. A vehicle may lose its coolant due to various reasons, which may include:

  • the engine is wearied out
  • harsh external conditions like extreme climate, rough terrain, etc.
  • rash driving
  • worn-out parts of the engine, etc.

Besides, coolant is a volatile fluid that tends to evaporate, which may also be one of the reasons for coolant loss. Let us look into some more reasons in detail:

Damaged Head Gasket

If the head gasket of a car's engine is damaged, the coolant can leak out rapidly. This leaked coolant can enter the combustion chamber, where it replaces fuel for a short time, and abnormal combustion can cause erosion in the system leading to engine failure.

Broken Reservoir Cap

Coolant levels can be disturbed if the radiator cap is damaged, which results in decreased reservoir pressure. This also leads to temperature rise and causes the check engine light to flash.

Damaged Radiator Hoses

Since radiator hoses are fitted close to the engine, the chances of melting or breaking due to intense temperatures are very high. This may cause the coolant to leak and erode the head gasket.

Radiator Leakage

Sometimes, substandard coolants cause the radiator walls to corrode, which leads to rust. The rusty walls of the radiator crack, eventually causing the coolant to leak.

Cooling System Damage

Coolant is a fundamental yet one of the many components that work simultaneously to maintain the engine's temperatures. These include:

  • Water Pump
  • Thermostat Housing
  • Radiator Fan

If any of these components work anomalously, they can lead to coolant leakage in different ways.

Is Coolant Loss Considered Normal?

Coolant leakage is inevitable, and some of the important reasons are listed above. But one exciting yet dangerous thing is that sometimes, coolant loss isn't even noticeable. 

Due to the presence of an overflow reservoir, a negligible amount of coolant is lost due to its volatility. This loss of coolant increases gradually as time passes. Experts believe that if the engine is perfectly healthy, the coolant might drop by 0.25" every four months, i.e., 1" drop per annum.

So, a change of coolant and cleaning of the radiator after every couple of years is strongly advised by the experts.