Radiator FULL, but reservoir nearly EMPTY after adding coolant

JayZeeBee
Sat, 10 Dec 2022 16:28:21 +0000
Maintenance/Repairs

I noticed recently the coolant reservoir was nearly empty in my 2008 Civic. Checked radiator, and could just see the coolant at the bottom of the neck, which I understand to be normal. Temp gauge reading normal.

Thought I had a possible leak, so I added some coolant to the reservoir last night and thought I’d see if it drops gain. Drove about 8 miles (most trips I take are pretty short).

This morning, checked and reservoir again nearly empty. BUT when I checked the radiator, there was coolant almost to the TOP of the neck.

So it SEEMS like coolant is flowing into the radiator, but maybe not flowing back? Idk. Trying to identify possible issues before I take it in. Any ideas? My knowledge of cars is pretty low, so maybe this is normal and I just don’t understand how the coolant system works.

Also trying to assess if this is a “don’t drive your car until you get checked” sort of thing, or if it is ok for <10 mi trips.

10 posts - 7 participants