crank bolt tightening debate

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snip
The units are irrelevant as long as the quantities are correct.

Normal operating conditions or not, a moment of force is commonly called torque.

Whatever that is, it is beyond me to see any relevancy to the bolt tightening debate.

What would this be good for - the bolt should remain lose "upon commencing operations"?

It's not the greater surface area that "holds fine threaded applications more tightly together," it is the smaller lead (the pitch in a simple bolt). <http://www.efunda.com/designstandards/screws/faste ners_intro.cfm?search_string=thread>

Galling is abrasion and fusion caused by friction, not heat cycling.

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tend
different
and
tend
If someone else would like to address this gentleman's comment above and his other assertions, then please be my guest.
snip for brevity
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http://groups.google.com/group/alt.autos.honda/browse_thread/thread/611ca6332c3f50e
Because no one came forward to help you I will explain it to you myself. Could be helpful when "educating college engineering students."
A quantity consists of a value (also called magnitude) and a unit (also called dimension), for example "4 quarts," or "1 gallon." Here, "4" and "1" are the values and "quarts" and "gallon" are the units of the quantities. In these examples the values and the units are different, but they both specify the same quantity because 4 quarts equal 1 gallon. So, it is irrelevant in what units a quantity is expressed, but it is common to choose units that yield easy to handle values - avoiding very small or very large numbers.
And if you are specific about the "other assertions" I will help you with those, too.
Now, would you please help me? I don't understand your first paragraph. But this could be because I am neither a mechanic nor am I a metallurgist, and I didn't have the benefits of "materials 101." When rewriting it, please pay particular attention to the implications of, "the cut of the threads does not tend to tighten the bolt," and, "The threads are helically cut on both coarse and fine thread designs, of course, so back-and-forth vibrating forces will tend to have the same effect on both." What would be the effects if the threads were not helically cut, and what bolts would these be?
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I just remembered why I hated school. Thanks for the memories.
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lower res pics are here:
http://www.snapfish.com/thumbnailshare/AlbumID1395672/t_6454773
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Since the below requires some kind of login, then if you send me the photo(s), I would be happy to post it as a query topic on the "Queries" page of my site.
Email: snipped-for-privacy@earthlink.net

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jim beam wrote:

ok, let's try this instead:
http://www.flickr.com/photos/38636024@N00 /
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I still dunno. I've seen galled steel flat washers and bolt heads various places before (but I don't recall where they have been), so I wouldn't have thought it was unusual. I would speculate that the torque we need to apply to break crank bolts loose isn't being directed to the threads but to the head, where the galled surfaces are responsible for the excessive break-loose torque. Pure speculation, though.
Usually crank bolts (Honda or otherwise) need to loosen a quarter turn or so before they come free, and then there is no evidence of the threads galling - leading me to the speculation of the galled head and washer surfaces being the key. That would also be consistent with the observation that the break-loose torque goes up over the years, if engine heat and/or vibration is important in the development of the galling.
I don't think we have enough to work with to come up with a definitive answer.
Mike
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have
You mean they are a result of?
Galled refers to a surface that has been rubbed by something else.

so
Are you sure you're not referring to the roughly quarter turn of typically 1/2-inch drive extension tool windup that occurs?
'Cause that will rotate about 45 degrees at 300 ft-lbs of torque. If more torque is required to breakloose the bolt, then even more angular deflection occurs. But it's not the bolt turning.

Are you saying you think the head and washer are adhering, and that's why the breakloose torque is so high?

Quite right.
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wrote

No, I'm uncertain if the galling is the result of other movement (either in torquing or in service) and that the galled surfaces are producing the excessive break-loose torque. I've dealt with galled threads before, and crank bolts just don't feel that way - once they back off a bit they always have been smooth for me. Disclaimer - I've only done a handful of crank bolts, not dozens or hundreds like pros encounter.

I have never used extensions - really! The impact socket rotates an estimated 1/4 turn before it takes off. I always watch it, trying to will it to turn ;-) I've never really kept track of how far it rotates to reach torque specs when tightening.

That's where I'm heading, but I don't really know if that's right. My opinion is still in freefall on this.

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snip

in
always
I suspect this is the consensus, and I think it's a good point to throw in the mix: Galled bolts are hard to free for a number of turns after the initial breakloose. This hasn't happened in the maybe three times I've loosened my 91 Civic's pulley bolt.

or
typically
Okay.
And no surprise about the impact wrench you're using. It's a popular method, by all reports here.

why
Okay.
Aside: If the thread's bolts are seized, I remain baffled at why the bolt head doesn't shear off the way they commonly do on certain suspension bolts.
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That's a good point.
Mike
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Michael Pardee wrote:

you can see from the pics that there are no binding problems with the threads. even the 91 which has been removed 3 times shows no signs of distress.
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snip

Any chance you can determine or narrow down what material the pulley bolts are made of?
For reckless academic fun.
'course, if you take out every pulley bolt in your local yard, this will guilt me into removing and then re-installing my 91 Civic's pulley bolt and painting the whole assembly with a line of pink frost glitter nail polish to ascertain movement (or not).
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wrote

That would settle the question decisively. It's just that none of us want to "bell the cat." And not many of us would go with pink frost glitter nail polish!
Mike
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wrote

bolts
polish
to
probably more of a Y-65P or R-510 nail polish guy
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Do they make nail polish in NH-526M?
--
TeGGeR

The Unofficial Honda/Acura FAQ
  Click to see the full signature.
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I know where you can get a bottle with small brush attached to inside of cap, probably a year supply and you may need little more than nail polish remover to remove it :)
wonder if they sell pink frost glitter in gallon cans ? that would be a great project color for an old honda CVCC

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robm wrote:

bet an auto paint store would have something close! House Of Kolor makes some interesting showcar paint.
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Michael Pardee wrote:

it's not - because bolts move! that's why there's a whole industry dedicated to the production of locking mechanisms for threaded fastners. usually, we only care about the ones that loosen because they are more likely to cause the failures.

which is consistent with lash of the pulley wheel!
> That would also be consistent with the observation

that's part of it, but ultimately, as we can see from the skid marks on the underside of the washer, the bolt is still free to turn. the question is, at what torque. once it is turning, that sob is still in there /way/ tight, and way tighter than when torquing to fastening spec.

depends if we've spent time doing this kind of work before!

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