Head bolt retorque?

Frank Rizzo

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Jul 25, 2007
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I've been lurking here for a while and just recently joined so I could search. I've been searching for a couple days and found some info on retorqueing head bolts after replacing the head gasket.

I've got 1600 miles on a new felpro stock head gasket with ARP bolts that were torqued to 70ft/lbs in the TSRM sequence. I used 5 passes, if I remember I went hand tight (no rachet), rachet tight then 20, 35, 50, 65, 70. That was over 6 months ago with 1600 hard miles. I ran a block test and a compression test at 1200 miles. Block test was negative, and compression test looked like this 185, 185, 182, 181, 180, 183 thats 1-6 cylinders. I did that comp test on 6/23/07. I also did one before the head gasket and 4 and 5 were in the 170's. now they are 180+. Not using any coolant, overflow bottle behaving normal. No smoke at startup or WOT, no mixing coolant in oil blah blah basically running perfect.

Now I know what alot of the top dogs here say, back them loose just like 10-15ft/lbs and then retorque one at a time. But I don't like the sound of that. And I also read that some people just put a torque wrench on them to see if they still hold XXft/lbs which I read is not correct because of static friction or something. This is what I was going to do. I have a digital snap-on torque wrench and new cam cover gaskets and grommets. What should I do? Just get in there and put 70ft/lbs or should I back them off and torque one at a time? I would think if they were loose, they would be loose as in less than 70ft/lbs? Like I said the car is running flawlessly, except for the occasional scrapeage because my car is too low.

Any tips, tricks, past experiences, bitch slaps, flames are welcome!
 

IJ.

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Mar 30, 2005
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I always back them off till they crack loose then pull them tight in sequence.

Any other way either leaves you open to
a) coolant leak under the gasket if you back them all off or
b) incorrect reading from the static friction on the fastener.
 

extendor

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Jul 23, 2007
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You say 1600 miles and you are considering a retorque. I might get my head bitten off here but in my opinion I think you are too late and everything is nicely settled. If it is not broke then dont try to fix it.

By the way that sounds like a nice car.
 

IJ.

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Frank: Correct

Extendor: Agreed usually but it's cheap peace of mind in case Frank is thinking of cranking some boost into it in the near future and if done correctly won't casue any further issues.
 

extendor

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IJ. said:
Frank: Correct

Extendor: Agreed usually but it's cheap peace of mind in case Frank is thinking of cranking some boost into it in the near future and if done correctly won't casue any further issues.

Felpro stock gasket was what put me onto saying leave alone. If they are similar to our Mr T stock gaskets or pattern types then I would have said go for a MHG for a power build.
 

IJ.

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Ext: Using the above technique I'd still retorque a composite as it's not so much the gasket crush that changes it's more the fasteners relaxing even after multiple uses to burnish the threads. (I'm a little paranoid on this subject)

Welcome to SM :)
 

extendor

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IJ. said:
Ext: Using the above technique I'd still retorque a composite as it's not so much the gasket crush that changes it's more the fasteners relaxing even after multiple uses to burnish the threads. (I'm a little paranoid on this subject)

Welcome to SM :)

Thankyou my friend. Much appreciated.

FR - just for interest. Did you use any lube on the ARP's or did you go dry or engine oil. The reason I ask is the loss of effective torque when you use higher friction lube or worst case - none at all!!!
Judging by your engines reliability (and thoroughness of info you reported) I would expect you used ARP lube. That should help you be confident that you wont stress the bolts beyond yield if you retorque.
 

Frank Rizzo

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Jul 25, 2007
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I used copper anti seize on everything that threaded into the head or aluminum along with reducing torque values by about 10%. I put ARP moly lube on the nose of the crankshaft where the timing sprocket and crank pulley go. I also put it on the crank bolt threads and torqued to 150ft/lbs.
 

IJ.

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Frank: Crank bolt should be 195 ft/lbs it's a TTY bolt.

I use antiseize on anything that screws into hot parts ie:exhaust and low strength loctite when into aluminium, high strength into iron/steel as I spin my motor fairly hard and it tries to revert to kit form ;)
 

Shytheed Dumas

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At the risk of getting bitch slapped myself, wouldn't the safest thing to do be to torque in sequence straight to 80 ft-lbs? It's enough higher to break static friction I would think, and would eliminate any risks that come with relaxing the bolts.
 

IJ.

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SD: Nope not even close it often takes 100+ft/lbs to break em loose so pulling back till they crack is the best way I've found to get an accurate retorque.

As you're NOT backing the tension right off it's safe enough to do it this way.
 

Shytheed Dumas

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Thanks IJ & Jon. I wouldn't have guessed 100 ft-lbs to break it, but if that's what it takes I can see a big difference between "just breaking" and backing off completely. I didn't retorque mine because I was afraid that backing off meant breaking the seal and it just didn't feel right. 76 ft-lbs has been more than good enough so far and after 1 1/2 years, I'm leaving well enough alone.
 

Frank Rizzo

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Jul 25, 2007
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Thanks for the past experiences MDCmotorsports and Shytheed Dumas. I will be doing the retorque Saturday morning.

I just have one more question for the gurus. What about all of the braces that are bolted to the head and block AFTER you initially torque the head? Like the turbo braces, exhaust manifold braces and intake manifold brace. Would those have to be removed to apply torque directly to the head bolts? And the turbo oil return also, all of these are bolted to the head and the block so I would think those would have to be removed in order for the head to be torqued. Any thoughts on this?
 

IJ.

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Frank: There should be more than enough "give" in all of the braces to allow the head to be torqued without undoing any of them.
(otherwise the braces would break their mounting points due to disimular expansion rates in the head and block)

We tend to view a motor as a very ridgid structure when in reality they move around much more than you'd expect.
 

extendor

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Jul 23, 2007
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Frank Rizzo said:
Thanks for the past experiences MDCmotorsports and Shytheed Dumas. I will be doing the retorque Saturday morning.

I just have one more question for the gurus. What about all of the braces that are bolted to the head and block AFTER you initially torque the head? Like the turbo braces, exhaust manifold braces and intake manifold brace. Would those have to be removed to apply torque directly to the head bolts? And the turbo oil return also, all of these are bolted to the head and the block so I would think those would have to be removed in order for the head to be torqued. Any thoughts on this?

What comment convinced you to do a retorque or was that already set in your mind. If any thing, check the torque on each one and call it a day as previously suggested.