Q: 99 mercury cougar with a 4 cylinder leaking antifreeze from the overflow hose but car is not over heating could it possibly be the

asked by on October 10, 2016

Antifreeze leaking from overflow hose car is not overheating it will start leaking then stops and then starts again

My car has 192000 miles.
My car has a manual transmission.

Good question. In my experience, I believe you have a water pump issue. Another issue could be the thermostat but generally speaking the thermostat will cause the engine to over heat. The water pump could be going bad though which is causing it to boil over sometimes.

Listen for noises under your hood, usually when a water pump is going bad it will squeak a bit. If you aren’t quite sure, have the coolant system flushed to ensure there is no rust or debris clogging your system.

  • Note: Mixing colors of antifreeze can cause serious problems with your cooling system. Make sure you NEVER mix colors. It causes corrosion and crystallization which could be detrimental to the life of your engine.

If you need assistance with this repair, consider YourMechanic, one of our mobile technicians will be able to go to your home to diagnose this issue and service your water pump and flush your cooling system as necessary.

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