Skip the auto shop - Our mechanics make house calls

Q: Car overheating after losing green fluid from radiator.

asked by on

My car had a radiator leak, but as long as I kept adding fluid there was no problem. My daughter forgot to put the radiator cap back on after adding fluid. After driving it for a while, she noticed and put the cap back. The car overheated soon after. I checked it out and noticed green fluid on the right side of the radiator. What is going on with my radiator?

A: The green fluid on the side of the radiator...

The green fluid on the side of the radiator could just be from the cap being left off. It also could be from a leak. I believe your car overheated because while driving with the cap off of the radiator too much coolant came out. This left room for air in the cooling system which got sealed in by replacing the cap. An air pocket in your coolant system could block coolant from being able to flow through the radiator and cool your engine down. I would enlist the help of a mechanic to help find your coolant leak so you don’t need to worry about the cap getting left off again.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Silhouette

Many different parts can cause the vehicle to overheat. The most common would be the thermostat, radiator, water pump, air in the coolant, or a coolant leak. When a vehicle overheats at idle the usual suspect is the radiator fans....

Q: Motor replacement.

Hi there. It is hard to say if you need a motor without knowing what occurred. If the engine made any noise or suddenly stopped and will not crank or start then there are some tests that need to be...

Q: Scheduled maintenance. 2002 Jaguar Vanden Plas.

I would recommend replacing the fuel filter every three years or 30,000 miles for most cars. This car does not give you an exact fuel filter replacement interval, so it should only be replaced when the fuel pump is replaced....

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...