There are no markings on the coolant reservoir. Should it be filled half-way or all the way?

 

THATS JUST AN OVER FLOW. MINE WAY ALWAYS IN THE MIDDLE

 

Why are you yelling Dave?

 

On mine it depends on the temperature, I like to keep at least 1/4 filled with fluid, but sometimes it drains itself completely out, and sometimes it is half-full, and I have no idea why, which doesn't help, but I have asked people this question before and they don't know why either

 

I filled it 1/3 full and I'll wait and see. Thanks.

 

Mine has a full cold line at about 1/3 full.