I have a 2000 Honda Civic with 125,000 miles.

About every 300-500 miles the coolant reservoir is nearly empty. I refill it and it disappears again. I have checked the oil and it is not foamy. The coolant reservoir is not overboiling. I have driving the car for 60 miles, parked it and waited for leaks on the ground and nothing is observed.

Where is this coolant disappearing to?

Thanks for your help!

 

Burning it? White smoke coming out of the exhaust at all?

 

No smoke of any kind coming out the exhaust. I'm going to put it up on the ramps today, fill up the reservoir, and let it run, go underneath it after it has been running for a while and see if i see any drips. Also the water pump was replaced along with the timing belt recently.

 

I have discovered the leak!

It is leaking from the thermostat gasket!

That should be an easy fix unless the bolts decide to get stuck.

Tips are appreciated!