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Head Gasket Failure

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Old Dec 30, 2018 | 03:04 PM
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Default Head Gasket Failure

Quick background:

I bought a used 6.0 a couple years ago from a junkyard that claimed it had been rebuilt.

I drove it around for a while with a damaged header bolt hole thread that was damaged beyond repair so instead of heli coiling it I picked up a freshened up and rebuilt head from a reputable machine shop.

I install the head (drivers side) following the proper procedure for head gasket swap.

I get everything back together, fire it up, take it for a drive and it runs great, however, I notice a ticking sound that sounds like an exhaust leak and some faint white smoke coming out of the drivers side exhaust pipe.

I remember having problems with cylinder 7 before, so I naturally went straight to that cylinder and pull the plug and my fears were realized... The plug is steam cleaned. The other 3 plugs on that side look great so it looks like its only cylinder 7 that is getting coolant.

I have a bad feeling that something is wrong with the engine itself which is why the junk yard "rebuilt" it. Maybe the deck is warped from it overheating, or potentially a cracked block. Im also pretty sure that the ticking sound I heard was not an exhaust leak but maybe something else from the head gasket. I did not have this sound before the swap. I could hear the tick at the collector and also coming out of the tailpipe.

So my questions are:
1) What could be wrong with my engine that could cause a head gasket leak in cylinder 7? Did I just screw up the swap? The deck was cleaned and the head was essentially new.
2) What could that ticking out of the exhaust be from?
3) If you were in my shoes, would you just do another gasket swap and hope for the best, or yank the engine and have it checked out?

We wont know anything for certain until I tear back into it again, but I just wanted to brain storm some ideas before diving back in. Im honestly thinking about just pulling the engine and having it rebuilt at a shop. Its bone stock and can use some upgrades anyway.

Last edited by Smitty454; Dec 30, 2018 at 03:20 PM.
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Old Dec 30, 2018 | 03:20 PM
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I bought a used 6.0 for just the block. Brought it to a machine shop and they had to cut the deck .005". Machinist said that was enough to cause sealing issues. he also said that it was most likely the previous owner overheated the engine a few times
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Old Dec 30, 2018 | 04:35 PM
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If more certainty is what you're after - I'd say it's time to pull it back out and have the soundness/straightness/trueness of the block and heads checked out.
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Old Dec 31, 2018 | 10:53 AM
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Originally Posted by '05Silvy
I bought a used 6.0 for just the block. Brought it to a machine shop and they had to cut the deck .005". Machinist said that was enough to cause sealing issues. he also said that it was most likely the previous owner overheated the engine a few times
See this is why Im thinking I should just pull the the thing and have it checked.
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Old Jan 1, 2019 | 01:47 PM
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....me too....
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Old Jan 6, 2019 | 09:09 AM
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I have a problem on my #7 cylinder also. My plug is always fouled and I am getting smoke out of the drivers side pipe only.
My smoke is oil related vs water related, This engine does have over 200k miles on it.
Have you done a coolant pressure test? I did on mine and no issues but I still get water out the driver tail pipe vs the passenger side tail pipe. I know we get condensation, but I see water droplets on,y on one side.
We also did a quicky compression test and #7 was within spec with the others I tested.
Last thing is to do a leak down test but with all the things we’ve seen it’s internal.
I think I am just going to have to pull this lq9 and rebuild it.
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Old Jan 7, 2019 | 05:41 PM
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Originally Posted by LS1 pwrd NOVA
I have a problem on my #7 cylinder also. My plug is always fouled and I am getting smoke out of the drivers side pipe only.
My smoke is oil related vs water related, This engine does have over 200k miles on it.
Have you done a coolant pressure test? I did on mine and no issues but I still get water out the driver tail pipe vs the passenger side tail pipe. I know we get condensation, but I see water droplets on,y on one side.
We also did a quicky compression test and #7 was within spec with the others I tested.
Last thing is to do a leak down test but with all the things we’ve seen it’s internal.
I think I am just going to have to pull this lq9 and rebuild it.
Funny, I saw your post and was going to comment about my similar problem. Im not going to bother with the extra tests. A steam cleaned spark plug and a little white smoke out of the exhaust is enough to tell me that there is some coolant leakage in that cylinder. Im going to pull the head in the next couple of days to see what I can find.
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Old Jan 7, 2019 | 06:02 PM
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I have seen twice in the last month trucks in the wrecking yard that hit something so hard it cracked the head between the exhaust manifold bolt holes and into the water jacket.
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Old Jan 7, 2019 | 06:38 PM
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I saw a truck hit hard enough that the passenger side head punctured the firewall. Not the engine or set of heads to buy.
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Old Jan 8, 2019 | 08:54 AM
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Originally Posted by truckdoug
I have seen twice in the last month trucks in the wrecking yard that hit something so hard it cracked the head between the exhaust manifold bolt holes and into the water jacket.
LOL...since we were talking about Cleetus in another thread;

https://www.youtube.com/watch?v=0uGm...youtu.be&t=433
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Old Jan 8, 2019 | 11:16 PM
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Well I tore the head off tonight. No obvious signs of damage or gasket failure. The only thing I noticed is the #7 combustion chamber is verrry clean!
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Old Jan 9, 2019 | 02:28 PM
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Originally Posted by gofastwclass
I saw a truck hit hard enough that the passenger side head punctured the firewall. Not the engine or set of heads to buy.
...or the cab to buy...
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Old Jan 9, 2019 | 04:47 PM
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Originally Posted by TipsyMcStagger
LOL...since we were talking about Cleetus in another thread;

https://www.youtube.com/watch?v=0uGm...youtu.be&t=433

heh funny to see him slumming it up in a pick n pull. of course damaging extra **** and making a mess. what a ding dong. that guy could **** up a wet dream.
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Old Jan 9, 2019 | 06:14 PM
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Originally Posted by truckdoug
heh funny to see him slumming it up in a pick n pull. of course damaging extra **** and making a mess. what a ding dong. that guy could **** up a wet dream.
Single digit IQ's get sorta boring after a minute or two...
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Old Jan 9, 2019 | 07:25 PM
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back on topic.. what do you guys think? Cylinder 7 is obviously getting steam cleaned by coolant. Nothing obvious on the engine side or on the gasket. Is this most likely an error on my installation or could this be a warped block/head?
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Old Jan 9, 2019 | 08:34 PM
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Water got in SOMEWHERE. Check inside the intake port. Maybe look at the gasket again, more closely.
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Old Jan 11, 2019 | 09:01 PM
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I wish I knew what your problem is.
But man is that clean looking.
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Old Jan 11, 2019 | 10:08 PM
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Straight edge and feelers will tell you if the head and/or block decks are warped. If they check out ok I say get new bolts and gaskets and run it.
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Old Jan 12, 2019 | 11:48 AM
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I've had two blocks that had cracked cylinder walls on number they were both blower motors and I think they went lean but I found it odd the same cylinders were the ones that cracked.
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Old Jan 12, 2019 | 01:06 PM
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have it pressure tested? yeah inspect the block too
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