added water to radiator after driving

Asked by Apr 15, 2017 at 05:20 AM

Question type: Maintenance & Repair

added water to radiator after driving
i drove a hijet for about 10 -12 km at 85kph and came back
home after getting out of car I opened the radiator cap with
a cloth hot water came out I let the steam out for 5-10
minutes and added around 1.5 litres of tap water then
drove it for 8-10meters to park it will it be okay?
ps: I did not do so because the engine overheated or
something only did it because I thought I hadn't checked
the water before starting to drive
i heavent started it for 5 hours now
when I added water it kept on going back for 3-4times then
settled on top

3 Answers


you may have air pocket in cooling system. try not to put tap water, it tends to corrode the cooling system. plus tap water will eventually evaporate. try using distilled water. with vehicle on, turn heater on full blast and fill till it overfills the radiator. make sure there no leaks.


Well first of all you never remove the radiator cap with a hot engine, as you found out it's just not safe. Now that you have only added water to the system you have thrown off the anti boil point and possibly the PH of the cooling system. As you didn't give a year make or model I suggest that you have the cooling system flushed and the thermostat replaced and all the hoses and belts checked and replaced if needed, this would be just a maintenance type of service to hopefully catch anything from happening in the near future to your cooling system. Theses nothing worse than sitting on the side of the road with steam rolling out fron under the hood.

1 people found this helpful.

The cooling system should always be filled or topped off when the engine is cold. Coolant and water is like anything else. When you heat it, it expands. That's why once the engine cooled down it took more to refill it. HTH. -Jim

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