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Head gasket external leak??

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9.5K views 13 replies 5 participants last post by  DMAXMatt450  
#1 ·
I have a 07 chevy lbz with 86k miles on it, and im leaking coolant slowly, i thought it was from heater core adapter coming out of the fire wall but its not, its not the egr because that is fully removed, its not the heater core line and nothing els i can see on top of the engine. I can see coolant dripping down from where the block meets the head on the rear passenger side of the block, and then drips down to my oil pan then to the ground. I am hoping it is not an external gasket leak i know that is more common for the 07 lbz gaskets to leak externally first, no white smoke and the upper coolant hose is never hard. Any ideas? Here are some pictures
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#2 ·
Get yourself a coolant system pressure tester or take it to a shop and get it tested for it, instead of guessing. I just went through this issue with my truck and well. Mine were the valves to my coolant filter. It was dripping and drying before touching the ground or anywhere else.

Its just a piece of mind and a place to start.
 
#3 ·
Thank you I will do that. im just wondering if there is anyone els that has seen a leak in this exact spot? I've been reading as many post as I can find on here about coolant leaks and head gaskets and im wondering if anyone has had this same exact situation?
 
#4 ·
That is a common spot to leak it seems but i would first test it to make sure no hoses or anything leaking up top and running around to that location till it evaporates.
 
#6 ·
I dont have experience myself but that is what I’ve been told.
 
#10 ·
Just thought I would give an update in case anyone else encounters this problem, I got a pressure tester From Harbor freight and applied 15 pounds of pressure I then saw that it was leaking from the turbo cooling line, it’s that little 4 inch piece of tube that bends in a 90 and goes down to the bottom of the turbo, The whole time I was thinking head gasket because it would leak out of the rear right passenger side block where the head meets the block! And without the pressure tester I couldn’t see where it was coming out of, I also couldn’t really see a puddle down in the V of the block until I did the pressure test, I tightened the hose down and we are good no more leaks.
 
#11 ·
Yep that makes sense. Thus why i mentioned doing a test before assuming its the gasket.
 
#14 ·
I had a coolant leak start the other day that looked like it was coming from the passenger side cylinder head gasket at the rear. After reading through this I looked down into the engine valley above and I could see it was wet. Pressure tested at work the next day and it was the coolant line going to the front of the EGR (I know I need to delete it). Sounds like there can be multiple leaks that can occur on the top on the engine that run down the back side and make it look like a head gasket. Thanks for the help everyone!!