Small Coolant Leak - Overflow Tube?

[ATX_Boxster]

i pulled my car out of the garage over the weekend and noticed that there was a small coolant leak just in front of the right rear wheel - basically the size of a quarter.

i ran a quick errand and when i got back, i parked the car and watched to see if I could tell where the leak was coming from. sure enough, i noticed a drop of coolant so i jacked up the side of the car and took a look. the reservoir tank overflow tube was wet on the inside, and it looked like a few drops had made their way out of the tube and then onto part of the exhaust before falling to the garage floor.

the original coolant tank was replaced last summer. i decided to pull the carpet again last night to make sure that things were dry and they were.

so what could be causing the leak? i thought maybe the coolant cap might not have been tight enough. i replaced the cap at the same time i did the tank. part number ends in 04... that was when i noticed that there was a lot of condensation on the roof of the trunk right over the coolant tank.



you could even notice condensation on the inside of the overflow tank gasket...



so - is my fairly new 04 cap bad? i'm assuming that the condensation is forming on the inside of the trunk and then back into the tank area and then out to the ground via the overflow tube.

FWIW - my coolant level is to the max line and the car runs at normal temperature according to the temp gauge on the dash.

TIA for any input...

[seningen]

Is your bleed valve open?

it is under the plastic cover held in place with that one bolt.

m

[ATX_Boxster]

thanks - i'll take a look at that tonight.

i do remember that when the tank was replaced and the system was bled, the bleed valve seemed a little suspect even though it was new. it was difficult to open. i think that the metal pins that pull the valve open had a hard time staying in place.

definitely more investigation is needed...

[kk2002s]

I have the condensation on the truck lid as well. I replaced the caps a few months back and that reduced the amount significantly, but I still get it. Some warmer days I don't see it. I'm going to try replacing the Bleeder valve 'O' rings to see if that reduces it. I have to think that warm fertile area against the cold metal is going to make condensation.
I keep my level about midway (+/-) Cold and I have only seen a quarter size drop on the garage floor from overflow tube twice in a year + (14k miles driven) ownership
Is that Hot or Cold Max Line level you have??
I have to think if you just had coolant done and it's at Max Line, cold, your seeing overfill on the floor

[JFP in PA]

I would pressure test the cap and the cooling system as well to make sure they are holding at the correct pressure. Quite often, even fairly new caps "pop" well below their rated pressure and need to be replaced.

[ATX_Boxster]

couple of more pictures that i took when i got home tonight...

the underside of the plastic cover over the bleed valve was soaked too.



i didn't see much coolant around the actual bleed valve though... does the coolant drain from here out of the middle of the tank and out the tube in front of the right rear wheel?



and as mentioned earlier, though my tank is essentially new...i've always been a little suspect of the bleed valve. it's hard to open because the metal pins pop out on either side of the valve when you try to open it.



so - do you guys think that all of this condensation is from my .04 fill cap, or bleed valve o-rings - or a combination of both. i'd like to order the parts from pelican tomorrow.

(jfp - not sure if i have the tools to pressure test the cap or the coolant system. may just bring it into the shop for that test once i can determine where the condensation is coming from...)

thanks -

[dany916]

ATX_boxster any luck finding the condensation origin?

[ATX_Boxster]

Actually I did, and I've been meaning to update this thread. Been busy...

A faulty bleeder valve and/or inner O-rings were the issue. The valve was replace and it came with the rings. Thankfully an easy fix.

My coolant tank was replaced less than 6 months ago, so it's essentially new. I'm surprised that the valve would go bad so quickly. Now at least I know what to look for and test when it goes out the next time.