Skip the auto shop - Our mechanics make house calls

Q: Resevoir Tank Over Full

asked by on

The Resevoir pulled coolant from radiator and overfilled. Temp. Gauge is slightly higher than normal, it's half way now. Is the radiator bad or going bad?

My car has 122297 miles.
My car has an automatic transmission.

A: The coolant can be over filling the reservo...

The coolant can be over filling the reservoir for a couple of reasons. Always start with the simplest options first. One of which will be a failed thermostat. You can bench test this by submerging the unit in hot and cold water and check for proper opening, but it may be easier to just replace it. Secondly the amount of coolant in the system can cause the reservoir to overfil. This would only happen until the levels came down to normal range. Another issue may be the use of multiple types of coolant in the system. You may want to flush the radiator and put in one kind of coolant (50/50 mix only). If the coolant is overheating to the point the fluid is expanding and causing the issue, you will want to make sure the fans are assisting the radiator as they should be. The very worst option would be a failed head gasket. They would likely cause a number of other issues with the drivabilty of the vehcile.

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・Save up to 30%

Get a quote

What others are asking

Q: Water temperature gauge fluctuates even after replacing the thermostat could it be the water pump

Hello, thank you for asking about your 2003 Honda Element. This can be many different things aside from the thermostat, such as a failing water pump, a failing coolant fan relay, a clogged radiator, or even potentially a blown head...

Q: Fuel pump not working properly.

Hi there. Without knowing the symptoms that are occurring with the car it will be hard to pinpoint what it is. Though it can be a fuel pump, those are not too common on this car. The majority of the...

Q: air sound on acceleration

Hi there If by HP increase you're talking about adding multiple stage NOS kit, then your OEM OBD-II codes will be irrelevant; as the software in the ECU is not factored in for aftermarket upgrades. You'll need to contact the...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...