My car is leaking antifreeze from below the drain plug. It's dripping from a small plastic tube right under the drain. I just flushed the coolant and now I'm concerned.

Asked by Oct 03, 2014 at 04:46 PM about the 1999 Mitsubishi Eclipse GS

Question type: Maintenance & Repair

8 Answers

I'm hoping it's just the o ring or the drain plug was overtightened. Or better yet, maybe I just overfilled it? That small tube looks like it is supposed to be a drain for excess antifreeze but I'm not a mechanic. Any insight would be appreciated as to why it could be leaking from there. Thank you.


Things to look for: That the plug is in tight enough. That you didn't over tighten and crack the plug or housing. That you didn't cross-thread the plug. Was it easy to hand tighten the plug when you replaced it? There is sometimes an o-ring on the plug. Did your plug have one? Did you put the o-ring back? You will probably need to drain the coolant and check out the plug and housing.


Excess coolant should go out the top side of the radiator into the overflow container. The small tube is to allow you to attach a drain hose and drain the antifreeze neatly by loosening the plug. It never works for me. /

The cheapest fixes and IMO the most likely of problems is the o ring or me over-tightening it. I just wanted to make sure I wasn't overlooking anything. I'll go pick up a new plug and o ring. Is there an apoxy or thread tape that is designed for that plug?


I think if you put in a new plug and o-ring, the leak will go away. Don't use anything on the plug unless the directions say to. Your plug/housing looks just like my Toyota's. My plug doesn't need any tape or sealant to seal.


PS, I just flushed my radiator a few weeks ago. Hand tighten the plug; don't use any tools. Snug it up real good but don't try to use extraordinary strength. Just tight like you're closing the pickle jar.

I have the same problem. Did that work?

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