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head bolt question

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Old Aug 7, 2007 | 08:30 AM
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I know they are torque to yield, and not suposed to be re-used, but has anyone actually had any issues from re-using them?

I've re-used them a couple of times (on different engines) with no ill effects
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Old Aug 7, 2007 | 09:03 AM
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cheap bastard... here's a hint, Ron and I found them in stock and for the best price at the Carquest warehouse behind Cortana Mall
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Old Aug 7, 2007 | 10:34 AM
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please dont reuse them.
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Old Aug 7, 2007 | 10:39 AM
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i havn't reused them but i have seen peoeple reuse them and then have the head gasket blow out after 100 miles or so.
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Old Aug 7, 2007 | 12:21 PM
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I re-used them on my 5.3, and someone else I helped do a head swapped we re-used his. I didnt have any problems with that, was just wondering if anyone personally knew what would be so bad about re-using them.

I mean honestly whats the chances of something happening? You have 15 (I think) head bolts holding the head down.

Imma try and pick a set up, I was just wonderin
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Old Aug 7, 2007 | 12:33 PM
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I would not try to re use them.
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Old Aug 7, 2007 | 12:40 PM
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just buy new ones ******.
BTW when you planning on pulling? tonight?
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Old Aug 7, 2007 | 04:05 PM
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Originally Posted by DLH2006
just buy new ones ******.
BTW when you planning on pulling? tonight?

Thats what its looking like since my dawg wants to do it tonight
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Old Aug 7, 2007 | 04:25 PM
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Originally Posted by white1
I re-used them on my 5.3, and someone else I helped do a head swapped we re-used his. I didnt have any problems with that, was just wondering if anyone personally knew what would be so bad about re-using them.

I mean honestly whats the chances of something happening? You have 15 (I think) head bolts holding the head down.

Imma try and pick a set up, I was just wonderin
Take a coat hanger and bend it a little, and it will return to its original shape. Bend it too much and it will remain bent. That is because you have exceeded the "Yield Strength" of the steel. If you continue bending the coathanger at the same location, it will eventually break.

When you tighten a bolt, it will always stretch some. As long as you don't tighten the bolt too tight (exceeding the yield strength) it will return to its original length when loosened. If you "Torque to yield" the bolt will be permanently stretched, and will never return to its original length. Just like the coathanger, if you reuse the bolt and stretch it again, it will be prone to breakage. Have you ever tried to remove a bolt broken off in the block?

Don't take a chance. Buy new bolts.
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Old Aug 7, 2007 | 05:41 PM
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Originally Posted by Yogi Bear
Take a coat hanger and bend it a little, and it will return to its original shape. Bend it too much and it will remain bent. That is because you have exceeded the "Yield Strength" of the steel. If you continue bending the coathanger at the same location, it will eventually break.

When you tighten a bolt, it will always stretch some. As long as you don't tighten the bolt too tight (exceeding the yield strength) it will return to its original length when loosened. If you "Torque to yield" the bolt will be permanently stretched, and will never return to its original length. Just like the coathanger, if you reuse the bolt and stretch it again, it will be prone to breakage. Have you ever tried to remove a bolt broken off in the block?

Don't take a chance. Buy new bolts.

im using new bolts this time, i was just currious i guess. thanks for that explination though
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