Coolant splashed over the engine

I recently bought a 2005 Honda Civic 190,000 miles, the car drives good and everything was perfect until I start driving the car on the highway, i noticed that after 45-60 mins of driving once I stop for any reason I found that the car is overheating like crazy so I turn it off immediately, and i also discovered that the coolant is pushed out the reservoir cap and splashed over the engine and the radiator itself is nearly empty, I just bought it and I don’t know much about the history of that car
Some background about the problem
1- only happens after a long drive
2- I changed the reservoir and the thermostat and the problem still exists
Some people said it maybe the head gasket, however i flushed the coolant system once and i found that it was clear as well as the oil and there is no white fumes coming out of the exhaust

Check and see if the radiator fan is turning on.


The head gasket possibility needs to be investigated. Seems the coolant is getting into a combustion chamber and out the exhaust, and exhaust gasses are pressurizing the cooling system, pushing out through the radiator cap. Good luck and please keep us informed. Or it could be a simple case of bad radiator cap, not holding pressure.


They are working, They keep turning ON and OFF about 10 mins after the car gets to it’s operating temperature

This symptom can be due to the cooling system not holding pressure correctly, often due to a small leak somewhere, or a faulty pressure cap. Try replacing the cap, see if that solves it. If not, ask your shop todo a cooling system pressure test.

Other possibilities

  • engine compartment fans operation ok usually, but intermittently not working. Next time it overheats, pop the hood & see if the fans are spinning like crazy or not.
  • ignition timing is incorrect
  • incontinent head gasket (car parked in driveway, remove the pressure cap, start the engine from cold, and look for bubbles rising through the coolant in the radiator, rev the engine a little to see if that has any effect. As the engine warms the coolant level will rise, may overflow the radiator and splash, so stop this experiment before the engine fully warms, & be prepared for all that, wear eye protection & monitor the dash coolant temp gauge)
  • radiator is clogged
  • water pump is faulty
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How can i confirm that the fans are working properly?
When i add coolant while the engine is running, once the engine warms up i see air bubbles going out and coolant level fall not rise, is that what you mean?
What is the other symptoms for water pump fault?

That’s not a confirmation of proper electric fan operation

Have you seen the plastic fan blades turning at high speed, and heard that whooshing sound?

Normally after how many minutes should the fans turn on if i’m starting a cold engine and leave it on idle
and for how long they will keep turning?

Since your engine is having overheating episodes, next time one happens pop the hood. That’ll be the easiest method. If the radiator fans are working correctly they will be spinning robustly. If you want to try the warm up at idle in the driveway test for the fans, on my Corolla the radiator fan turns on about 5-15 minutes from when I start a cold engine and let it idle in the driveway. How long it takes depends on how cold the engine is to begin with. This time will vary from car to car. On my Corolla once it turns on it stays on for appx 2-3 minutes at idle, but that also depends on the ambient temperature and whether all the engine parts are fully warmed up or not. I’ve marked the dashboard coolant temp gauge dial where the fan turns on, and turns off. On my car it turns on a little under halfway, and off a little past halfway.

I don’t add coolant at the same time as looking for air bubbles (indication of head gasket leak). Adding coolant will create bubbles on its own. The bubbles – if any exist – are caused by exhaust gas from a cylinder breaching the head gasket and into the coolant. There tend to be many small bubbles coming up through the radiator, rather than a few large ones. If you google you can probably see a u-tube what they look like. If you see a few large bubbles that seem to burp their way out the radiator, that’s usually caused by air trapped in the cooling system; i.e. not a head gasket problem. Shops have more definitive tests for head gasket failure than this, but this sort of test is a good place for a diy’er to start.

Common symptoms of faulty water pump

  • overheating
  • noisy operation
  • leaking

Radiator cap. Radiator cap. Radiator cap. Radiator cap. Radiator cap.