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possible blown head gasket UPDATED WITH MORE PICS

73azbronco

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^^^^^^^^This? Although I think that would just result in lose bolts, not broken ones.
 
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m_m70

m_m70

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The washers were chamfer up. I'm just surprised that there was no water/coolant in the oil or oil in the water/coolant%). Will work on getting the broken bolts out tonight and clean things up then pull the other head and see how that looks.
 

Rustytruck

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When I replace a head gasket I put the head on without the gasket and run the bolts down with a speed wrench by hand and see if the bolts will clamp the head without a gasket. running the bolts in by hand you should be able to feel any tough bolts that may need thread chasing. Then I pull the head and install it with the gasket. The extra 10 minutes will insure a good assembly. Be sure to check the head dowels, Put the head dowels in the block and when you assemble without the gasket and with the bolts down try to slip a feeler gauge between the head and block by the dowel if you cant you should be good to go to pull the head and install the gasket.

http://www.carsdirect.com/car-repair/how-to-calibrate-a-torque-wrench
 

blubuckaroo

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Did the head get washed out in the area of the leak? It may not be noticeable visually. A light resurface may be in order.
 
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m_m70

m_m70

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Not sure what you mean by "washed out". I checked it with a straight edge last night and it seemed ok in poor lighting. Going to check it today in better light to get a better look. I only drove it about 200 yards once the gasket blew completely out. It didn't show any signs of having a bad gasket/broken bolts until it completely let go.
 

blubuckaroo

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Not sure what you mean by "washed out". I checked it with a straight edge last night and it seemed ok in poor lighting. Going to check it today in better light to get a better look. I only drove it about 200 yards once the gasket blew completely out. It didn't show any signs of having a bad gasket/broken bolts until it completely let go.

The hot combustion leaking through a small hole will have enough velocity to wear away the castings. I've seen it damage iron heads and blocks. Aluminum would probably be damaged easier. It may not have happen in your case but it's important to do a close inspection.
 
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m_m70

m_m70

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Cool. Makes sense. I will be cleaning up the head and block hopefully tonight and should get an idea where I'm at then. I think I'll be ok there though as the engine only ran for 2 minutes max with the leak.
ARP is replacing the bolts - I am sending the broken bolts to them so they can analyze. I'm sure this will take some time though. I will post the results when I get them. I know there are some interested folks out there.
 

blubuckaroo

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Cool. Makes sense. I will be cleaning up the head and block hopefully tonight and should get an idea where I'm at then. I think I'll be ok there though as the engine only ran for 2 minutes max with the leak.
ARP is replacing the bolts - I am sending the broken bolts to them so they can analyze. I'm sure this will take some time though. I will post the results when I get them. I know there are some interested folks out there.

How could you know when the leak started??:?
 

EricLar80

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I would take a look at the top bolts and see if they bottomed out when you were torquing them down. That would put all the stress during combustion on the bottom bolts, causing them the break.

Just an alternate thought...

Any chance you could upload a hi-res and up-close image of the fracture surface? It would be obvious if you over torqued it vs a brittle bolt vs fatigue.

Eric
 
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m_m70

m_m70

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How could you know when the leak started??:?

I guess it could have been leaking before it finally blew but I had no smoke or exhaust leaks until it finally gave way. Never did smoke only the massive compression leak.
 
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m_m70

m_m70

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I would take a look at the top bolts and see if they bottomed out when you were torquing them down. That would put all the stress during combustion on the bottom bolts, causing them the break.

Just an alternate thought...

Any chance you could upload a hi-res and up-close image of the fracture surface? It would be obvious if you over torqued it vs a brittle bolt vs fatigue.

Eric

Ill see if my phone will take a clear shot. If not I will get a high res shot tomorrow and post it.
I got three out of the for broken bolts out tonight. they were not bottomed out and came out relatively easy with a reverse cut drill bit. The last, as always, is not being as cooperative.
 
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m_m70

m_m70

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not the greatest pics but here you go.........
 

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EricLar80

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I would tend to say those are overstress failures but hard to tell with photo. ie, over torqued. Were those new bolts, wondering why they are already pretty rusty.



I'd also be taking the torque wrench in to be checked out by a calibration lab.

They are rusty because they broke a while ago.
 
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