Headgasket?!? Or Somewhere else
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From: San Antonio TX
Headgasket?!? Or Somewhere else
Well long story short. I just had a new motor built and put in. It's a built ls6 with ported heads and ls2 intake. We use head studs, GM 3 layer gaskets with ported heads and Ferrera valves. After a month of having it installed and going through break in period perfectly, no WOT hits, and nothing more than freeway entry speeds, I'm seeing tons of coolant in my oil. I didn't think it could be headgaskets again, I JUST HAD THEM DONE!!! Before installation we had the block cleaned and heads milled so surface was completely flat before headgaskets were installed. How is it that I could have soooo much coolant in the oil? Where are other places it could be coming from?
*** I didn't a coolant leak down test and it did loose pressure through the tank.
**** I also did a compression test and all cylinders had good compression.
WHERE DO I CHECK NEXT???
*** I didn't a coolant leak down test and it did loose pressure through the tank.
**** I also did a compression test and all cylinders had good compression.
WHERE DO I CHECK NEXT???
Last edited by Darth_Vetter; Aug 23, 2015 at 04:05 AM.
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From: San Antonio TX
Cylinder on drivers side closest to fire wall did have a smashed spark plug. Looks like cylinder actually made contact with the spark plug, but compression was good.
Last edited by Darth_Vetter; Aug 23, 2015 at 04:02 AM.
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Any misfires? If not, were any of the plugs really clean, i.e., no carbon? That is one telltale for it getting into the cylinder.
The GM gaskets are pretty forgiving and typically seal well. If all was flat and clean with a good surface finish, I would be surprised if the gaskets leaked with proper torque on the studs. How were the heads tightened in place and to what torque value?
How much were the heads ported? There have been instances where porting has been a little too aggressive resulting in very thin walls and leakage of fluids into the motor.
The GM gaskets are pretty forgiving and typically seal well. If all was flat and clean with a good surface finish, I would be surprised if the gaskets leaked with proper torque on the studs. How were the heads tightened in place and to what torque value?
How much were the heads ported? There have been instances where porting has been a little too aggressive resulting in very thin walls and leakage of fluids into the motor.
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None of the plugs were washed out or clean. The only plug with moisture at all was the plug that was smashed in the picture, but the compression was good.
It's on the side without the supercharger tho, so thank God. I'm gonna try and pull that side first and see what I need to do and go from there.
It's on the side without the supercharger tho, so thank God. I'm gonna try and pull that side first and see what I need to do and go from there.
Any misfires? If not, were any of the plugs really clean, i.e., no carbon? That is one telltale for it getting into the cylinder.
The GM gaskets are pretty forgiving and typically seal well. If all was flat and clean with a good surface finish, I would be surprised if the gaskets leaked with proper torque on the studs. How were the heads tightened in place and to what torque value?
How much were the heads ported? There have been instances where porting has been a little too aggressive resulting in very thin walls and leakage of fluids into the motor.
The GM gaskets are pretty forgiving and typically seal well. If all was flat and clean with a good surface finish, I would be surprised if the gaskets leaked with proper torque on the studs. How were the heads tightened in place and to what torque value?
How much were the heads ported? There have been instances where porting has been a little too aggressive resulting in very thin walls and leakage of fluids into the motor.
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From: Dear Karma, I have a list of people you missed.
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Good place to look as well as valve spring seats. Depending on the springs being used, the seat cutter can cut into the coolant passageway if the machinist is sloppy or just takes out too much material. You'll still have good compression since the coolant is leaking directly into the crankcase.
Do a coolant system pressure check.
HTH
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That plug looks horrible !!! Bent electrode can only happen if something broke in that cylinder--valve made contact with the piston or a foreign object got into your intake manifold
Unless you had the head shaved GM always recommends using the stock graphite layered gasket as they are very forgiving----
The only way coolant can get into your oil is thru the head--since on a LS there is NO coolant in the intake manifold---
Hate to say the heads have to come off again---and you need to find the cause---otherwise next time you may face catastrophic damages
Unless you had the head shaved GM always recommends using the stock graphite layered gasket as they are very forgiving----
The only way coolant can get into your oil is thru the head--since on a LS there is NO coolant in the intake manifold---
Hate to say the heads have to come off again---and you need to find the cause---otherwise next time you may face catastrophic damages
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From: Columbia South Carolina
The head gasket debate can rage for years, as well as what is the best oil etc. Use a gasket from a well known source and you will be fine as long as you follow proper cleaning/prep and torque specs, regardless....
You need to pull the heads to inspect why your spark plug was smashed and inspect cylinder walls and piston for any damage. Replace your head gaskets with whatever you prefer, I usually go with GM MLS or Cometic, Fel Pro makes great gaskets as long as you buy their most expensive stuff.
If it isn't a head-gasket its poorly ported/milled head or cracked cylinder wall/block, no other way coolant can get into your oil.
Pull the heads and inspect. Reinstall using good gaskets, and MOST IMPORTANT thread lube with proper torque sequence and specs.
For it being a poorly machined head, it would only make sense if the coolant is leaking directly into the motor, if it was blowing past the head gasket you would more than likely see white smoke out the tailpipes and bubbles in the radiator/overflow tank.
My bet is poorly machined head.
Either way, stop driving or running the motor with coolant in the oil, good way to wipe out bearings real fast.
You need to pull the heads to inspect why your spark plug was smashed and inspect cylinder walls and piston for any damage. Replace your head gaskets with whatever you prefer, I usually go with GM MLS or Cometic, Fel Pro makes great gaskets as long as you buy their most expensive stuff.
If it isn't a head-gasket its poorly ported/milled head or cracked cylinder wall/block, no other way coolant can get into your oil.
Pull the heads and inspect. Reinstall using good gaskets, and MOST IMPORTANT thread lube with proper torque sequence and specs.
For it being a poorly machined head, it would only make sense if the coolant is leaking directly into the motor, if it was blowing past the head gasket you would more than likely see white smoke out the tailpipes and bubbles in the radiator/overflow tank.
My bet is poorly machined head.
Either way, stop driving or running the motor with coolant in the oil, good way to wipe out bearings real fast.
Last edited by 175rgr; Aug 24, 2015 at 09:39 PM.
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From: CA.
St. Jude Donor '13-'14-'15
Forgot to mention but it escapes me if all the block head bolt threads are blind or if any of them go into the water jackets----Look this up to be sure-- If some go into the water jackets then they need to be sealed with thread sealer
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St. Jude Donor '08
ALL of the head bolt holes are BLIND HOLES. 
If the head bolts are or were ever reinstalled and there was liquid in the bolt holes, it will RUPTURE the block at the bottom of each head bolt pocket whe the bolts are torqued in place. The coolant hydro crack the bolt hole
I agree. Before you pull the heads. Pop off the valve valley cover and see of you have any ruptured bolt pockets. Pressurize the cooling system and look for water /coolant droplets.
Were the head studs easy to install (thread into the block) when you installed them???
Bill
If the head bolts are or were ever reinstalled and there was liquid in the bolt holes, it will RUPTURE the block at the bottom of each head bolt pocket whe the bolts are torqued in place. The coolant hydro crack the bolt hole
I agree. Before you pull the heads. Pop off the valve valley cover and see of you have any ruptured bolt pockets. Pressurize the cooling system and look for water /coolant droplets.
Were the head studs easy to install (thread into the block) when you installed them???
Bill
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From: San Antonio TX
Coolant system did not check. It lost approx. 5psi every 30 seconds
Good place to look as well as valve spring seats.
Depending on the springs being used, the seat cutter can cut into the coolant passageway if the machinist is sloppy or just takes out too much material. You'll still have good compression since the coolant is leaking directly into the crankcase.
Do a coolant system pressure check.
HTH
Good place to look as well as valve spring seats. Depending on the springs being used, the seat cutter can cut into the coolant passageway if the machinist is sloppy or just takes out too much material. You'll still have good compression since the coolant is leaking directly into the crankcase.
Do a coolant system pressure check.
HTH
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Joined: Dec 2011
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From: San Antonio TX
Hey Bill,
This was a reinstall on a completely new block that was also cleaned and looked over by the machine shop. I will look at the pockets just to make sure.
This was a reinstall on a completely new block that was also cleaned and looked over by the machine shop. I will look at the pockets just to make sure.
ALL of the head bolt holes are BLIND HOLES.
If the head bolts are or were ever reinstalled and there was liquid in the bolt holes, it will RUPTURE the block at the bottom of each head bolt pocket whe the bolts are torqued in place. The coolant hydro crack the bolt hole
I agree. Before you pull the heads. Pop off the valve valley cover and see of you have any ruptured bolt pockets. Pressurize the cooling system and look for water /coolant droplets.
Were the head studs easy to install (thread into the block) when you installed them???
Bill
If the head bolts are or were ever reinstalled and there was liquid in the bolt holes, it will RUPTURE the block at the bottom of each head bolt pocket whe the bolts are torqued in place. The coolant hydro crack the bolt hole
I agree. Before you pull the heads. Pop off the valve valley cover and see of you have any ruptured bolt pockets. Pressurize the cooling system and look for water /coolant droplets.
Were the head studs easy to install (thread into the block) when you installed them???
Bill
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From: Dear Karma, I have a list of people you missed.
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I had this happen to me a number of years ago. I THINK it was on #7 cylinder, but it's been a long time and I've slept several times since then. The shop wanted to weld/patch. I said NO WAY. "I want a new head señor." They did.
"Core shift" was the cause in my case on some factory LS7 head castings. It happens sometimes.