Blown Head Gasket

BONES

BONES

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We went out to the sand this week and had a blast. I thought the car was running great with no issues. We did a super fast run and I noticed my temp gauge was climbing. Let it cool for quite a while, and my buddy said he saw white smoke puffs out of one side of the exhaust. I limped it back to camp and after it cooled I checked it all out. The radiator was low and after refilling it I fired it back up. Radiator fluid started spitting out of the exhaust, not a lot, but enough, and that’s when I knew…
 

Looking for recommendations for a shop to fix it in the San Diego east county area. We have a trip planned the 17th and not sure if it’s feasible to have it done. Hopefully it’s just replacing the gaskets and everything else, i.e. the heads, are fine. 
 

What do you guys say?
thanks in advance. 

 
The gasket probably lost contact due to a head warping. For sure you will want the surface of them checked. May just need a light fly cut.

.

 
Might be fastest to pull the heads and do it yourself. Machine shop will be the longest delay. 

 
Carwashguru said:
Might be fastest to pull the heads and do it yourself. Machine shop will be the longest delay. 
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That’s what I’m afraid of. I’m not afraid to do it, I just don’t have the time either as of late. 

 
it shouldn't take very long to get a head cut. but if you cut one i believe you supposed to cut both but im no engine builder. has it been running hot did it detonate might of stretched the head bolts or the gasket might of just let go 

 
Not sure if i have ever seen a LS head warp,  They will get soft, so might need a head, lot of work to risk it on a soft head,  

 I have had mine up to 265 degrees and not lost a gasket,  

  • Did it detonate, 
  • Does it have a fueling issue, 
  • Is the system water lines correct
  • Does it have a thermostat, if no does it have the bypass freeze plug in the pump, 
  • Is the Block soft
  • Is the Head soft
  • Did water get in the oil pan and cause damage to the bearings  

Hopefully just a gasket, but a lot can go wrong in this situation, 

Then you can decide, or it might have, when the heads are off, Valve springs are a item that should be serviced like CV's, also does it need Valve ect

  • Check Valve seats 
  • Check Spring tension,  
  • New valve guides 
  • Trunnion Replacement, or Trunnions, I have had failures with all brand of trunnions exempt for comps 
  • Does it have Chromoly pushrods, cheap upgrade, 
  • Do i change the lifters at least the guides, GM OEM only for Guides, 

This is what i would be thinking when the heads are off, 

 
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When Alper chimes in, all I hear is Cha Ching, Cha Ching......buy once cry once....Nothing is cheap or easy on toys....I think the only thing worse than Sand toys is  Ocean toys...

 
I've never done an LS.  But, I've done a 350 in a Suburban, PU, several times.  You climb in there w/it.

If you can't take it apart in 4 hours...you should turn in your man-card and sale your stuff and buy a pink golf-cart.

I'm guessing, that in your rail, you'll get in apart in about 2 hours.     

Youtube is your buddy/friend

If you mill one, you have to mill the other.  Well, not actually, but it would be foolish to not pull both heads and take both heads to the shop.  You wouldn't know if it wasn't flat until you pulled it.  It would be like changing the timing belt and not doing the waterpump, clutch and throw-out bearing.  It would be so half-a@@ed.

 
Realbadlarry said:
When Alper chimes in, all I hear is Cha Ching, Cha Ching......buy once cry once....Nothing is cheap or easy on toys....I think the only thing worse than Sand toys is  Ocean toys...
Click to expand...
What these cars go through, it is always a gamble, Domfather would fix one thing and then another issue happened, for example lost a Rocker, changed the rocker but the lifter had a issue, so then they pulled the head to change one lifter and the cam had a dent in it that broke the lifter again and the pushrod and the rocker, and metal is in the motor

He has lost 4 trips due to this and now he wants to park the car due to frustration 

At the end of the day, it depends on the persons budget and what they are willing to deal with, 

A head gasket can be minor or major issue, it is hard to say,     It is like a blood clot, some do ok, some dont,  Being almost 50 years of age, i want to know when i spend the money to go to the dunes, that what i worked on will work,  

What i mentioned above is a task list to meet a end goal, not a to do list,  Start with each task and go from there, everything above should be checked,  @Realbadlarry I dont works on cars at the dunes not even my brother car, if he did not prepare, then it is on him.  Its my Vacation just like everyone else, 

 
Stinky said:
I've never done an LS.  But, I've done a 350 in a Suburban, PU, several times.  You climb in there w/it.

If you can't take it apart in 4 hours...you should turn in your man-card and sale your stuff and buy a pink golf-cart.

I'm guessing, that in your rail, you'll get in apart in about 2 hours.     

Youtube is your buddy/friend

If you mill one, you have to mill the other.  Well, not actually, but it would be foolish to not pull both heads and take both heads to the shop.  You wouldn't know if it wasn't flat until you pulled it.  It would be like changing the timing belt and not doing the waterpump, clutch and throw-out bearing.  It would be so half-a@@ed.
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I never see them warped, they use a really good casting, use a long body file 250-grit to clean the head gasket off, i use a rigid 16'' long style, go 45 degrees one way then another, do the same to the block 

MAKE SURE to look from the side of the cylinder to the water jacket on the block for any cranks, that should be the number one thing to start on, the cracks will go front cylinder into the oval water jacket, if there is a crack, 

If you can work on a SBC this is way easier 

DECKING HEADS, this is not a older SBC, so if the heads are decked the pushrods will need to be checked for length, they are non adjustable, the Lifters need to have .060 to .080 some lifters can push .095 of preload, So decking the heads can change the Preload depending on the lifter, 

Some tools to start with 

17 in. Auto Body Hand Sander (harborfreight.com)

Trick Flow Specialties TFS-90306 Trick Flow® Valve Spring Compressors | Summit Racing

Pushrod Length Measuring Tool 4.3 5.3 5.7 6.0 6.2 LS1 LS2 Lq4 lq9 LS - Michigan Motorsports

Trunnion upgrade 

COMP Cams 13702-KIT COMP Cams Retrofit Trunnion Kits for GM LS Series | Summit Racing

All this can be done easy at home, head gaskets are directional so pay attention, also look at the oil, is it milky this will determine a different task list, 

 
well the actual thing you should try to find out is why it failed. is it tuned too hot   bad gas with no octane left causing it to dentate. if it was detnotating you might see some marks on the piston or metal on the spark plug. mabe injector is clogged fuel pressure right causing a lean condition??? could of been running hot or mabe the gasket wore into the head or block deck. chacks. either way it is usually a easy job on a rail and gaskets aren't too expensive so pop it apart and do some investigating.  

 
Jersey_Jeff73 said:
well the actual thing you should try to find out is why it failed. is it tuned too hot   bad gas with no octane left causing it to dentate. if it was detnotating you might see some marks on the piston or metal on the spark plug. mabe injector is clogged fuel pressure right causing a lean condition??? could of been running hot or mabe the gasket wore into the head or block deck. chacks. either way it is usually a easy job on a rail and gaskets aren't too expensive so pop it apart and do some investigating.  
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This is what needs to be done,  ^^^^  show some pics,  what do the pistons look like, what do the plugs look like,  what head gasket was on it, 

 
J Alper said:
I never see them warped, they use a really good casting, use a long body file 250-grit to clean the head gasket off, i use a rigid 16'' long style, go 45 degrees one way then another, do the same to the block 

MAKE SURE to look from the side of the cylinder to the water jacket on the block for any cranks, that should be the number one thing to start on, the cracks will go front cylinder into the oval water jacket, if there is a crack, 

If you can work on a SBC this is way easier 

DECKING HEADS, this is not a older SBC, so if the heads are decked the pushrods will need to be checked for length, they are non adjustable, the Lifters need to have .060 to .080 some lifters can push .095 of preload, So decking the heads can change the Preload depending on the lifter, 

Some tools to start with 

17 in. Auto Body Hand Sander (harborfreight.com)

Trick Flow Specialties TFS-90306 Trick Flow® Valve Spring Compressors | Summit Racing

Pushrod Length Measuring Tool 4.3 5.3 5.7 6.0 6.2 LS1 LS2 Lq4 lq9 LS - Michigan Motorsports

Trunnion upgrade 

COMP Cams 13702-KIT COMP Cams Retrofit Trunnion Kits for GM LS Series | Summit Racing

All this can be done easy at home, head gaskets are directional so pay attention, also look at the oil, is it milky this will determine a different task list, 
Click to expand...
I love this, your help is hugely appreciated.
 

 And honestly your posts are spot on, going to the desert is a huge investment, I don’t want to be working on things out there. I have a buddy in our group who doesn’t even check his oil before going out, needless to say I have stopped helping him when he continues to break. 
 

I pulled all the panels, cleaned every nook and cranny, drained oils and fluids, and I’m going to pull the motor and send it over to someone my equipment mechanic recommended. Alper, there was no water in the oil and no oil in the water, it’s not detonated, at least I don’t think so because it still sounds decent, so I’m hoping for the best. But also expecting the worst, that’s why I want it all checked out by someone who knows exactly what to look for. Although I’ve torn down a few 350s and 327s, I’m no professional. This motor was built to handle a supercharger and time and money was put into it, I want it done right so there’s no problems, at least for a while  

Also figured while I have the motor out, I’d pull the tranny, so it’s going over to McDowell to get split open. It felt good while out there, but there’s not many opportunities that I have the motor out of the way, might as well do it too. 
 

I just hope I can get this bad boy put back in the car in the next few weeks. 

 
what i meant about dentition was pre ignition like you would hear a ping or light wrap under load. it causes very high cylinder pressures and could lift the head among other bad stuff cracked ring lands melted piston just depends on how bad it happens. being boosted adds to the stress on the cylinder sealing.  btw mcdowell is a great choice and good luck im hoping to make it out around the 17th thru newyears 

 
Jersey_Jeff73 said:
what i meant about dentition was pre ignition like you would hear a ping or light wrap under load. it causes very high cylinder pressures and could lift the head among other bad stuff cracked ring lands melted piston just depends on how bad it happens. being boosted adds to the stress on the cylinder sealing.  btw mcdowell is a great choice and good luck im hoping to make it out around the 17th thru newyears 
Click to expand...
Sometimes minor detonation will just eat the head gasket out from between the block and head, eventually exposing the water jacket. 

If any signs of lean running/detonation, might be worth making sure the rings didn’t lose tension

 
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