Coolant cap question
 

Does anybody know exactly how the cap on the coolant reserve tank works? Yesterday I saw it leaked a little out, probably because I may have had a little too much coolant in the system. But I heard someone saying that once it vents, it has to be replaced. :wtf I figured it works like any other cap, it vents whenever the pressure goes beyond normal, and doesn't mean it's fried?? I know the thing's only 9 bucks, but damn, I just bought this one just before winter.

My understanding is that it's normal and they're all designed to release pressure in the event that it's over-pressurized. The easy fix is to take a little out of your reserve tank so when the radiator over-pressurizes, and throws fluid back into the reserve tank, it's got more room to throw more fluid.

Hope this helps.

Ehh, problem solved, hasn't leaked in almost a week now. I guess I just had too much antifreeze in there, I forget it's a closed system.

maybe you had air in the system?

Nah. I learned how to bleed this thing properly last summer. I did the same thing a few months ago, filled the antifreeze to about 3/4" above the fill line, and it leaked out. So I put 2 and 2 together . . if the system is well sealed, it bleeds off excess coolant out of the cap, the only place it can come out.