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Discussion Starter · #1 ·
I have posted about this before. I have a ZL1 lid with a reinforced brick. I have a 8 gallon tank in the trunk that mysteriously loses fluid constantly. It’s like it’s full one day, I can drive it for a week or two, sneak a peak in the tank and everything is dandy… drive it, see my IAT2 shoot up, check the tank, POOF it’s gone. I have checked the brick TWICE now. I pulled it off yesterday, checked it. It’s fine. I have slight oil film and some tiny puddling on the inside of the supercharger (which I know is natural) but I see NO signs of oil/water mixing. I fill the tank up almost all the way, and I drive it fifty miles on the highway with NO hard pulls, I was even stuck in an hour worth of traffic, I was just cruising the whole time. Arrive at my destination and I check the tank and I can tell it’s gotten slightly low again. I shit you not this JUST started as soon as I changed from distilled water to 50/50 for winter. I was fine all year! Change it out and it’s eating it up! I made sure I made an even exchange with fluids I drained and added.

I see no leaks under the vehicle, I’ve put that brick under 30PSI of air while submerged in water and not a single air bubble…

I’m tired of keeping gallons of distilled water in my trunk IN CASE OF AN EMERGENCY, it’s stupid at this point. It HAS to be that brick, that’s the only thing it could be.

So please… Somebody point me in the direction of a brick that won’t fail me. I’m making 912 to the wheels and I need something that’s gonna hold. I just dumped all this money into the car and I refuse to see it lock up from a failing brick.
 

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Fun pedal, Few doors
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“It has to be that brick” is an unsupported statement.
You have multiple connections, pump and tank and some twenty foot of hose.
Why are you so convinced it’s the brick… when the brick is the ONLY component that has been eliminated by testing? Seems illogical.

Now go find the leak.
 

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Fun pedal, Few doors
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Rig up a way to temporarily put 3 or 4 PSI on the tank (system) without the pump running.
One of those garden type pump up sprayers is a good way to prevent over-pressuring.
While it’s pumped up, bleed any air off at a brick fitting.
Leave it sitting with low pressure for a while.
observe for clues

I have a schrader on my tank for this purpose
 

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Discussion Starter · #4 ·
“It has to be that brick” is an unsupported statement.
You have multiple connections, pump and tank and some twenty foot of hose.
Why are you so convinced it’s the brick… when the brick is the ONLY component that has been eliminated by testing? Seems illogical.

Now go find the leak.
How could I possibly be losing that much fluid and not notice it? The only theory I can’t replicate is the internal pressure of the fluid and the external air flow pressure going through the brick if that makes sense? That’s the only other thing I can think of. I have ran the pump numerous times to find leaks, let it idle and idle and drive it and let it idle, I see no leaks where I’m losing 4-6 gallons out of nowhere.
 

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Discussion Starter · #6 ·
Rig up a way to temporarily put 3 or 4 PSI on the tank (system) without the pump running.
One of those garden type pump up sprayers is a good way to prevent over-pressuring.
While it’s pumped up, bleed any air off at a brick fitting.
Leave it sitting with low pressure for a while.
observe for clues

I have a schrader on my tank for this purpose
I will try this and see how it goes.
 

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2011 Thunder grey coupe auto
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Just a thought , if this started after switching to coolant does your tank have a drain ? Is it possible drain leaks under pressure or temp now that it’s been cycled? Leaks can be dependent on pressure, temperature or vibration or a combination of each . I’ll usually start at low pressure if looking for a leak , let sit and check . Increase slightly and repeat if it’s a difficult to find one .
 

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Discussion Starter · #8 ·
Just a thought , if this started after switching to coolant does your tank have a drain ? Is it possible drain leaks under pressure or temp now that it’s been cycled? Leaks can be dependent on pressure, temperature or vibration or a combination of each . I’ll usually start at low pressure if looking for a leak , let sit and check . Increase slightly and repeat if it’s a difficult to find one .
What has peaked my curiosity is if the vacuum from the engine being pulled through the brick PLUS the pressure from the pump in conjunction is more than the 30psi I am applying to just the inside of the brick, therefore that’s where the fluid is going? But has me stuck is I don’t smell any burning coolant. My plugs look flawless too.
 

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What about the brick o rings on manifold? You can remove lid, leave brick and manifold bolted in . I don’t remember if lid has any sensors but remove if it does plug holes flip over and fill with water and pressure test through manifold fittings. It doesn’t sound like it’s making it into the combustion chamber though from what you’re describing . I’d be looking at rest of system as well.
 

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I had a similar issue. For me it was the intake hose to the pump. It hadn't been fitted onto the Pierburg pump correctly. Not only was it crooked, it caused the AN line to tear and propogate up the line past the barb.

As recommended I say you double check all your connections, especially those hose ends that might not be AN fittings.
 
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