coolant leaking from head stud nut

lincolnlocker

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that is correct. I have coolant leaking out of the top of a head stud nut. its the driver side rear outside corner to be exact. oil is clean, no coolant in it. just running out and down. what could cause this and any way to stop it for now?
 

webb06

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that is correct. I have coolant leaking out of the top of a head stud nut. its the driver side rear outside corner to be exact. oil is clean, no coolant in it. just running out and down. what could cause this and any way to stop it for now?

On my 6.4 when this happened the block was cracked. You could try removing the stud and putting on some pipe dope to temporarily fix it.

Since its an exterior stud I don't think you'll have any trouble with coolant and oil mixing
 

lincolnlocker

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Sounds to me like the stud itself is cracked.
how could that be? it was tq'd to spec and then hot retq'd by mike himself.. wouldnt think they would crack. but there still shouldn't be coolant coming out of there unless head or block is cracked or gasket is jacked right? I dont know weather or not the stud goes through a coolant passage due to not knowing what the internals look like or how coolant flows through any of it. I have never had to mess with that aspect of a 7.3...
On my 6.4 when this happened the block was cracked. You could try removing the stud and putting on some pipe dope to temporarily fix it.

Since its an exterior stud I don't think you'll have any trouble with coolant and oil mixing
what part should the dope go on? just the top where the nut is or threads on the block side too? I would think that it could potentially hurt whatever is cracked worse.. but again, I have never had to deal with this issue.
 

webb06

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how could that be? it was tq'd to spec and then hot retq'd by mike himself.. wouldnt think they would crack. but there still shouldn't be coolant coming out of there unless head or block is cracked or gasket is jacked right? I dont know weather or not the stud goes through a coolant passage due to not knowing what the internals look like or how coolant flows through any of it. I have never had to mess with that aspect of a 7.3...

what part should the dope go on? just the top where the nut is or threads on the block side too? I would think that it could potentially hurt whatever is cracked worse.. but again, I have never had to deal with this issue.

The portion of the stud that threads in to the block. Don't put any around the nut. That will mess with the proper torque.

Pretty certain the studs don't go through the coolant passages
 

lincolnlocker

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The portion of the stud that threads in to the block. Don't put any around the nut. That will mess with the proper torque.

Pretty certain the studs don't go through the coolant passages
so that would help if the block was cracked. but what if head is cracked? and it leaks out very easily. I have a pressure gauge plumbed in to the coolant system and it barely registers any pressure and its leaking out of the nut....
 

lincolnlocker

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would it be a stupid idea to take the nut off and put some permatex around the stud(not on the threads) and then re tq the stud? or be better to just let it leak untill I can get around to pulling the motor?
 

isootmypants

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would it be a stupid idea to take the nut off and put some permatex around the stud(not on the threads) and then re tq the stud? or be better to just let it leak untill I can get around to pulling the motor?

Honestly I would just clean off the area, leave it torqued and just smear over it for now
 

golfer

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none of the 7.3L studs go through coolant passages...

around them, yes...but no (7.3L) studs are exposed to coolant (unless the block is cracked).
 

TyCorr

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Thank you for the clarification sir!! guess im gonna be on the hunt for a block

yeppers.



well ***.....

thanks fellas.

That blows man! 7k out of a rebuild. About $1100 per 1k miles.

Are you just going to get a forged motor and swap things over? Get back to it?

After this experience, unless you can afford one from swamps or nltd, id use a stock fr motor.
 

lincolnlocker

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That blows man! 7k out of a rebuild. About $1100 per 1k miles.

Are you just going to get a forged motor and swap things over? Get back to it?

After this experience, unless you can afford one from swamps or nltd, id use a stock fr motor.
prolly. but no time soon. this one is balanced but 30 over so I dont know what im gonna do yet..
 

DEEZUZ

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that sucks man. I know you work your truck too. All the more reason for me to remain stock in the most important aspects.
 

DocBar

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This might have nothing to do with Lincoln's issues, but I'm a big believer in sleeving the cylinders. There are cracks that magna-fluxing can't find. Cheap insurance, imho. Going .xxx over in a diesel just isn't the same as in a gasser. I'd rather stay closer to stock compression. Just my .02 worth.
 
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