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Intake manifold or head leak?

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Old Jul 28, 2019 | 08:23 PM
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Default Intake manifold or head leak?

I am a little confused on this. The car has been parked in the driveway for 2.5 weeks while I was waiting for new axle bearings to be pressed on.

Once I got everything sorted out today, I fire the ls1 up and I look under the hood and I see water trickling down by the head. The water comes out in spirts and it is just that, clear water not an orange coolant colour.

So I immediately think f*ck the head gasket is gone. Just my luck. But then, I keep watching it and it appears to have water pooling up further back in the manifold area (see pics). So now I am thinking maybe it is the intake manifold gasket leaking and it runs down the crevice of the head?

To throw me off even further, after about 10-15 mins it totally stops all together. Which has me wondering if water from the rain storm made it into the cowl and was maybe running it’s way down the engine? So now I am totally stumped and trying to figure out how I can tell what my issue is?

video of leak:

pics of wet areas





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Old Jul 28, 2019 | 08:43 PM
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They are good at water leaking from the cowl onto the intake.
There is no water in the intake so it's not coming from there. Clear water isn't antifreeze so my guess is puddled rain water.
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Old Jul 28, 2019 | 08:46 PM
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Also if it is rain water consider yourself lucky, Rain water has been known to leak past the intake into a cylinder while sitting and hydro locking when you try to start it bending or breaking a rod or breaking the starter off the block.
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Old Jul 28, 2019 | 09:02 PM
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There is no coolant that passes through the upper or lower intake manifold? Really? I thought for sure there was. But I am used to the old 3800 I had.

So basically if this is not rain water I’d be looking at a head leak?
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Old Jul 28, 2019 | 10:38 PM
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Originally Posted by LETZRIDE
There is no coolant that passes through the upper or lower intake manifold? Really? I thought for sure there was. But I am used to the old 3800 I had.

So basically if this is not rain water I’d be looking at a head leak?
Yeah the intake is dry. If it was coolant it wouldn't be clear. Likely water from a leaky cowl.
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Old Jul 28, 2019 | 11:37 PM
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replace your PCV hose...
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Old Jul 30, 2019 | 09:58 AM
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Originally Posted by LilJayV10
replace your PCV hose...
Can I just replace it all with a catch can? Or do I need a specialty hose to replace it and attach to a catch can?
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Old Jul 30, 2019 | 10:20 AM
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You see that fitting near the corner of the head? That is the steam vent. Verify the o ring in there is good and the bolt is tight. A slow leak right there will puddle exactly where it is puddling
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Old Jul 30, 2019 | 11:14 AM
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Originally Posted by Darth_V8r
You see that fitting near the corner of the head? That is the steam vent. Verify the o ring in there is good and the bolt is tight. A slow leak right there will puddle exactly where it is puddling

Thats what I was thinking, it seems to be coming right out of the crossover tube that bolts there to my eyes.
DO NOT just start randomly tightening that peice down, you risk stripping the threads.
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Old Jul 31, 2019 | 04:09 PM
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Originally Posted by Darth_V8r
You see that fitting near the corner of the head? That is the steam vent. Verify the o ring in there is good and the bolt is tight. A slow leak right there will puddle exactly where it is puddling
Sorry, which fitting? I feel like an idiot because I don’t follow which you are referring to. Thanks!
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Old Jul 31, 2019 | 07:58 PM
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I'd almost bet it was rain water, You said it was clear and antifreeze isn't and the car sat through a rain storm, What else could it be?
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Old Jul 31, 2019 | 08:48 PM
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well is it low on coolant?
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Old Aug 1, 2019 | 09:19 AM
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The steam vent fitting (red arrow)


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Old Aug 4, 2019 | 04:30 PM
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Originally Posted by LLLosingit
I'd almost bet it was rain water, You said it was clear and antifreeze isn't and the car sat through a rain storm, What else could it be?
Let it sit for a few days and finally got to firing it back up. Same thing as soon as it fires up it looks like it is wet and water starts forming and coming up from the furthest point you can see on the bottom part of the intake / head near the front.

why does it only come out when running and not when sitting if it is rain water? That’s what has me stumped. And the fact that it looks clear.

I am going to try and take it on a long run this week (20-30 min drive) and see what happens
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Old Aug 4, 2019 | 05:24 PM
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Because it starts to leak when it heats up and builds up pressure. I'm with Dath-V8r on the steam crossover being the possible culprit. Inexpensive fix if that's what's causing the issue too.
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Old Aug 9, 2019 | 12:10 PM
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That REALLY looks like it's coming from the crossover tube, the only doubt is why it's clear water, a guy would think there would be some coolant coming out, but maybe not.
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