Coolant leak & puddle under rear carpet, but replaced tank less than 4 months ago. - 986 Forum - The Community for Porsche Boxster & Cayman Owners

chromecarz00 · 03-16-2021, 05:26 PM

As the title says - found some coolant leaking when i was out and about today. Maybe a quarter cup worth?

When I got home, the drip was maybe 15 drops worth. Coolant tank was slightly low, but have noticed that when the car is up to temp.

Mild puddle in the trunk, no residue on any of the hoses, or on the tank itself anywhere.

Miniscule hissing noise from the cap, but no residue at all to show leakage from there. It's the updated version as well, so that shouldn't be in.

Anyone have any ideas?

Beelzy · 03-16-2021, 06:35 PM

Hissing noise from the cap? That is not normal.

porschefan76 · 03-16-2021, 06:36 PM

Hi! Harbor Freight sells an expansion tank testing kit for $89.99. Should allow you to pressurize the tank and listen/watch for leaks. Just a suggestion, good luck!

Racer Boy · 03-16-2021, 07:00 PM

It's an updated cap, but how old is it? I had a two-year old cap Porsche cap fail, so it's possible. If that's the problem, it's the best of all the possibilities!

chromecarz00 · 03-16-2021, 08:21 PM

Thanks all for suggestions.

The cap was changed at the same time as the coolant reservoir - 4 months ago.

I may pressure test, or just try to refill it and see what happens when I start it.

flouese · 03-17-2021, 02:57 AM

My trunk was flooded even though my tank was only 2 years old. Went ahead and replaced it. Turned out the issue was a loose clamp on the original tank. Note to self; self check the easy stuff first. Lesson learned!

chromecarz00 · 03-17-2021, 06:36 AM

Quote:

Originally Posted by flouese

My trunk was flooded even though my tank was only 2 years old. Went ahead and replaced it. Turned out the issue was a loose clamp on the original tank. Note to self; self check the easy stuff first. Lesson learned!

Well, I guess I'll go out there and try and find the leak!

blue62 · 03-17-2021, 07:00 AM

In your first picture the first hose on the left is showing a powdery residue under and around the hose clamp.
Could be a leak or a leak from the past.
Pressure testing the system is your best starting place to correct the issue.

chromecarz00 · 03-17-2021, 08:16 AM

Quote:

Originally Posted by blue62

In your first picture the first hose on the left is showing a powdery residue under and around the hose clamp.
Could be a leak or a leak from the past.
Pressure testing the system is your best starting place to correct the issue.

I ordered a pressure tester off Amazon and will leak it down as soon as I can! Heopfully tomorrow

blue62 · 03-17-2021, 08:31 AM

Quote:

Originally Posted by chromecarz00

I ordered a pressure tester off Amazon and will leak it down as soon as I can! Heopfully tomorrow

Keep us posted on what you find

blue62 · 03-17-2021, 10:19 AM

Reread the thread.
The hose with the powdery looking residue I pointed to is in the second picture not the first.
Sorry

Rob175 · 03-17-2021, 01:26 PM

1. loose hose clamp
2. bad hose
3. bad cap (even though you said it's "new' might still not be the latest version)
4. non-OEM tank (lots of crappy replacement tanks for less money out there but in the long run it's wiser to pay the price and get the "real deal" from Porsche

chromecarz00 · 03-23-2021, 05:47 PM

Just a quick update here... Turned out to be a defective tank. Pelican parts was a little bit of a pain to deal with, but they eventually made everything right.

My new issue is - I'm not sure what kind of coolant I have in there right now and I want to avoid the potential of creating the gel by mixing... So, my current plan is to get a coolant/water ratio measuring tool from pre stone, and figure out what the coolant ratio to water ratio is right now. If it's lower than, say 40/60, I was thinking of adding some kind of water wetter or something like that to help augment the cooling abilities. I've heard lots of good reviews, but also some iffy ones... I'd like to do a flush this year when I get back from overseas, but want something to hold me over until then.

Thoughts?

Secondary plan is to get some coolant tests figure out how good the coolant is to help me decide when to get the flush done - later this year or next year

Stl-986 · 03-23-2021, 05:52 PM

believe you are way over thinking it. If your concerned, just drain the coolant and replace it. It's an easy job and pretty cheap. With what your 1st & 2nd plan is you will spend more time doing that then it takes to just drain & replace. As long as whoever put it in last didn't use DexCool you wont need to even worry about the tests.

ike84 · 03-25-2021, 08:15 AM

Quote:

Originally Posted by chromecarz00

Just a quick update here... Turned out to be a defective tank. Pelican parts was a little bit of a pain to deal with, but they eventually made everything right.

My new issue is - I'm not sure what kind of coolant I have in there right now and I want to avoid the potential of creating the gel by mixing... So, my current plan is to get a coolant/water ratio measuring tool from pre stone, and figure out what the coolant ratio to water ratio is right now. If it's lower than, say 40/60, I was thinking of adding some kind of water wetter or something like that to help augment the cooling abilities. I've heard lots of good reviews, but also some iffy ones... I'd like to do a flush this year when I get back from overseas, but want something to hold me over until then.

Thoughts?

Secondary plan is to get some coolant tests figure out how good the coolant is to help me decide when to get the flush done - later this year or next year

A common misconceptions is that different "color" coolants will not jive if mixed and create sludge. This isn't always the case. Pedro did a pretty nice write-up of it on his site, and many other sites confirm what he says. I can vouch for the safety of mixing OAT type coolants without consequence (both in my 986 and other vehicles).

Sent from my POCOPHONE F1 using Tapatalk

78F350 · 03-26-2021, 04:36 AM

Quote:

Originally Posted by ike84

A common misconceptions is that different "color" coolants will not jive if mixed and create sludge. This isn't always the case. Pedro did a pretty nice write-up of it on his site, and many other sites confirm what he says. I can vouch for the safety of mixing OAT type coolants without consequence (both in my 986 and other vehicles).

Sent from my POCOPHONE F1 using Tapatalk

I totally agree on the safety of mixing a different OAT coolant, but highly recommend that people know what they are putting in. There are still some coolants out there on the shelf that will turn the Porsche coolant into red Jello. One of the salvage cars I bought had that happen and the engine was trash.

I keep a jug of G12 (pink) around for the couple cars that still have Porsche or G12 in them. When I drain or flush, they get Zerex OAT or similar filling them back up.