to change a Honda Accord 1988 model timing belt

No such thing was intended. A lot of people who work strictly on cars have
never heard of a slug wrench. I am demonstrating that I have some
specialized experience re torquing (or untorquing) bolts. I was trying to
explain how bolts can be torqued without a wrench, yada yada. You're
oversensitive. (Now that's an ad hominem, or a suggestion. Your choice. Just
notice I didn't go ballistic when you said I was lying about the Grade 8
bolts, jerk.

No. See the bozo guy's post.

True Value carries the Grade 8 bolts loose.

It's not worth my time to continue this discussion with you.

 

it can and it does. for a simple citiation, check out:

http://www.sheldonbrown.com/gloss_p.html

and read the section labeled "pedal" and note the reference to precession.

it doesn't continue to tighten indefinitely - it reaches equilibrium.

why? it ony needs to be initially set to hold it in place. anything
subsequent to that would come out in testing.

with respect, i've bounced on a day-old pulley wheel bolt. i weigh 200
lbs. at 18" from center, assuming i can exert a momentary "weight" of
300 lbs, that's 450 ft.lbs. and that shifted it. static weight alone
[300 ft.lbs] didn't.

i know. i said other cars.

try some fords or vw.

it's the pulley, not the bolt. i invite you to either operate the
engine without a woodruff key or calculate the inertia of a 10 lb pulley
wheel.

again, that's assuming no lash in the pulley. but there is. otherwise
there would be no need for the woodruff key.

but that's an example that proves my point. i don't understand how you
can accept this fact that bolts move in service in one situation, but
not another. you accept elastic distortion, right? if there's
distortion of one component more than another, there's relative
movement. it may not be large enough to see with the naked eye, but it
does occur.

 

ok, i see your conceptual problem - you're focused on the bolt. it's
/not/ the bolt that's lashing here tegger, it's the pulley wheel. if
you don't believe me, run the car without the woodruf key and tell me
whether the pulley rotates or not. /then/ figure out which direction
the pulley is receiving the highest velocity impulse. once you've done
that, you'll see which way the bolts turns as it goes along for the ride.

and btw, the impact driver has a very low mass anvil, compared with a
real hammer. and have you tried hammering a wrench to break bolts free?
sometimes it works, sometimes it just messes up the bolt. my point
is, the impulses an impact driven bolt receives are very high torque and
very short duration. to say that you can't get these in a crankshaft is
incorrect. that's why you have springs in the middle of your clutch
drive plate. without them to mitigate high impulse, you hammer out
bearings, gear cog tooth facings and drive shafts.

 

and there's nothing about precession either, which is a gross omission.

 

That's what the Woodruff key is for. If there was any relative motion
between the clamped parts, the bolt would LOOSEN, not tighten.

The theory that it tightens is so much total hokum I can't believe anyone
is falling for it.

After investigating this for myself in Google, I an even more convinced you
guys are barking up the wrong tree.

The engine's rotating/reciprocating mass is greater than the resistance
offered by the various things added on to it.

The bolt does not turn. Period.

I've been doing some extensive digging in Google, and I can find ZERO
ZERO ZERO mentions of this supposed thing.

IT DOES NOT EXIST.

YES! But the impact wrench's anvil is travelling at HIGH SPEED when it
makes its impact. Remember HORSEPOWER? You can make lots of horsepower with
very little torque and little mass.

And since the anvil is so light, the impact must necessarily be of short
duration, since the anvil lacks the mass to be able to sustain the impact
for long.

Comparing the effect of a short-duration, high-speed impact wrench to the
slow, lazy, massive engine is to compare apples to horse puckies.

Apples to horse puckies again. In this case, you have the weight of the
entire car behind those clutch springs, not just a few pulleys.


How come NOBODY can come up with ANY references to this? BECAUSE IT DOES
NOT EXIST. There are treatises commonly available on all sorts of bolt
tightening problems (I linked to two), but this rotation after final
tightening thing DOES NOT EXIST.

It's WRONG, jim. WRONG. The theory behind it is WRONG. Have you discovered
a new mechanical phenomenon that nobody else has in 300 years? I think not.

Bolts do NOT tighten, they LOOSEN if there is relative movement between its
clamped parts.

 

Ah, there's a word for what we're talkng about! Thanks. That gives me more
ammunition to refute your argument.

Your comparison of bike pedal and car crankshaft is not a valid one, for
one major reason:
A bike pedal bolt directly transmits torque as its primary function. The
crank bolt simply clamps two masses together. Torque is transmittred by the
mass, not the bolt. This is a very critical distinction.

By your own admission, I am focusing on the bolt, not the mass attached to
it. You are committing ths same sin, but in reverse.

Consider that if the clamped mass can move in ONE direction, it follows
that it can move BACK IN THE OTHER. And for your theory to work, the
clamped masses would have to move back and forth repeatedly.

Since it is much easier for the bolt to back out (releasing tension) than
to screw in some more (increasing tension), the bolt in a such a joint
would tend to LOOSEN. And if you do your own Google searches, you'll find
ALL references to clamp-bolts and precession referring to LOOSENING.

This back-and-forth causes an effect known as "fretting", which ultimately
LOOSENS the bolt.

The Honda bolt does not loosen because it has been tightened to a position
that will remain undisturbed until somebody disturbs it.

If you fail to tighten a Honda bolt sufficiently, it will FALL OUT, not
tighten more. My neighbor three doors down had just that happen to his
Prelude years ago. His neighbor replaced the timing belt, but lacking a
torque wrench, he just tightened the crank bolt to what felt right. Well,
tight it was, but NOT TIGHT ENOUGH. *Precession* from the clamped mass
BACKED THE BOLT back out again and the pulley fell off on the highway!

The theory that the bolt tightens flies in the face of everything I've been
able to find. It flies in the face of logic.

The joint, once correctly torqued, does NOT move. That bolt gets harder to
remove NOT because it tightens more from engine rotation, but from
corrosion, and (I think) "settling" at the surface texture level.

 

sorry dude, that's fundamentally wrong. the pedal spindle is /not/
subject to torque as a function of operation. it rotates as a result of
precession. as it tightens. r/h threaded wheel nuts on the left side
of vehicles loosen /if/ other measures are not deployed in design.
that's why big rigs /all/ have l/h threads on the left side of the vehicle.

not so if the impulse in one direction is more than the other.

if it's too loose, it'll wobble, not just lash.

sorry dude, joints of this type can and do move. the woodruff key
limits the degree of that movement, but it moves all the same. i don't
know why this isn't taught more frequently - maybe because it freaks
people out?

i've given you a bunch of examples that don't seem to work for you, but
i'll try again. next time you remove a driveshaft, on the wheel end,
look closely at the splines. that cannot possibly rotate, right? it's
splined and torqued. /but/ if you look closely at the splines, you'll
see a distinct boundry between the face where they mesh and the face
where they don't. on each and every tooth. that's the result of lash.
and that lash could result in the loosening [or tightening] of the end
nut - that's why it's staked [loosening being the disaster you wish to
avoid].

why is the pulley bolt not staked? if it's tightening, it doesn't need
to be!

 

<snip>

I must say, this thread has been very educational. Early on I had trouble
explaining what I knew by logic, because I didn't know the terms.

I learned about fretting, precession, recession, and the difference between
direct torque and clamped-mass applications. I even learned that the name
for a simple one-closed-end industrial wrench is a"slug wrench".

Thanks to jim and Elle for all that. Now, back to the battle!

Then why aren't other car's pulleys staked? They're all installed so that
the bolt will LOOSEN as the engine turns. The setup is otherwise identical
to the Honda one: Plain washers, woodruff key, no thread locker, etc. These
are just as difficult to remove as Honda bolts, and NONE comes loose once
tightened properly.

A bike pedal bolt's principles of operation is not the same as a
clamped-mass bolt's operation. You cannot use the two as equivalants.

jim, the theory of tightening after final setting is bunk. You will not
find any references anywhere to *tightening* precession in a clamped-mass
application because there is no such thing. You WILL find scads of
references to *loosening* precession in a clamped mass, because there IS
such a thing.

 

I have found no explanation for the pulley bolt's excessive tightening on
the web by anyone that sounds the least bit like it came from a bona fide
expert.

The explanations that do exist predominantly speculate it's either "heat
cycling," rust, or both.

Whatever heat cycling means insofar as it causes the bolt to tighten. My
theory re the heating up of the bolt, and so its stretching, etc. is the
only one that makes sense to me.

Your claim that the breakaway torque tends to be higher than the tightening
torque is true. Problem is, your boltscience site says the breakaway torque,
if higher, should be only a little higher.

You are just repeating yourself at this point. I won't torture the newsgroup
and repeat myself. I assure you, your opinion is heard.

I would still prefer you not link my "pulley holder tool" site to yours. I
may change its location if you continue to do so. The reason for this is
what you wrote on October 25th. You posted, "The last thing I want is errors
on the site. Errors cost credibility. Ego is not worth it if it leads to
errors. I research this stuff as best I can, but sometimes I need to rely on
a best-guess... You may not believe this, but I have no ego whatsoever when
it comes to this site.... I have NO ego and a very thick skin. "

All this led me to believe that if I went to the trouble of providing
information to you on certain subjects, then you would throw out ego and
treat it fairly.

I don't think you've kept up your end of the implied deal.

Your statements about my theory at my site are derisive and IMO ego-laden.
Yet you have only your own theory to rebut my theory.

If you said instead something like, "I disagree with Elle re why the bolt is
so tight, and this is why... ", then that would be one thing. But instead
you flat-out assert my theory is wrong. It subtracts from the credibility
and authority of the site, IMO.

You can't prove my theory is wrong. Nor can I prove yours is wrong. I'm
going on my best guess, just as you're going on yours.

Just saying.

 

Not the one Jim's talking about.

As long as the bolt isn't heated such that its diameter reduces relative to
its crankshaft receptacle.

 

Exactly.

 

Reasonable enough.

I'll change the text to that.

 

I changed my site earlier today to indicate that this matter was my theory.

Much as I want to believe that there's no way the bolt is actually axially
loaded per what 300+ ft-lbs of torque would produce, no other explanation
makes sense to me.

If this bolt is truly "special," then I'm betting what's special about it is
the material.

Anyway.

 

i disagree. my experience is that they're /much/ easier to remove.
i've worked on many different types of vehicles over the years and i've
yet to experience a pulley bolt quite like the honda.

dude, with respect, i gave you /two/ examples early on. you've latched
onto pedals, and to your credit, you seem to have used it as a reason to
check into some of this subject, but you've not addressed the other
example i gave you, the locking ring for a fixed gear bike, which is a
purely rotational reaction, not precessional like the pedal. lock rings
tighten in use. if you'd ridden a fixed gear bike, you'd know. you can
start riding with it loose and a couple of rides later, that thing's
locked solid. no heating going on there. and more importantly, you can
initially feel the drive sprocket "float" when you resist pedaling, and
you can feel the float get less & less each time as the lock ring
tightens. you need to look more into the whole lash concept. and check
some driveshaft splines.

for precession? you're not looking. the left side of big rig wheel
lugs are l/h threads and they tighten in use. that's why service techs
have chuffing great 1000 ft.lb impact drivers. same for pedals on bikes.

this is not related, but as a theoretical thinking question, do bike
wheels get stronger as spoke tension is increased? please, no cheating
by looking it up - work it through.

 

And I've changed mine.
http://www.tegger.com/hondafaq/faq.html#crankbolt

I think it's only fair I be allowed to include a new page expanding on my
reasons for my beliefs, which have been greatly strengthened by my
research.

Additionally, I have emailed the Bolt Science website at the email address
on their Contact page. Getting a repply is hit-and-miss with most Web
sites, but if I get an answer I'll share it here. And if it can be
determined that I'm wrong, I will issue a public apology to you, and make
the necessary corrections to my site. If you're wrong, I expect the same
from you.

My next door neighbor is a graduate physicist (no kidding!). He'd be ideal
to ask this question of, but unfortunately he's one of the least
approachable people I know. Too bad.

There are a number of "special bolts" used in various locations on many
Hondas. Suspension, transmission casing to engine/body, crank bolt, and
several other locations. Their "specialness" seems to differ based on their
application.

In the case of the rear supension, they're normal 10.9 bolts, but they have
unusual features, like fine threads, fluting on their shanks, and nylon
inserts in the threads.

 

On second thought, I take that back; there's nothing to apologize for.

I simply defended a sincere and strongly held viewpoint, and did so without
resorting to insults, name-calling, ad-hominem arguments, or gratuitous
jargon.

 

if you want the best possible automotive example of heat cycling or rust
on a honda, look at the exhaust system and its multiple fasteners.

feel free to discuss...

 

Just my opinion:

I give the reasons for my beliefs at my web site, so of course you should
feel free to do the same. You should also feel free to rebut every reason I
give for my theory. That's in the spirit of healthy technical debate.

What I don't think is constructive, though, is simply saying, "Elle's site
is wrong." Elaborate on why you think it's wrong, and I will think it fair.
For whatever my puny opinion is worth. It will also, IMO, help maintain
integrity.

It's not a crime to propose why some phenomenon happens.

Here's my two cents on how to promote optimal group problem solving on the
internet or anyplace else:

When I'm right, I do not expect--and do not want--an apology from anyone on
technical matters. Similarly, I don't generally issue apologies when a
theory or hypothesis I put forward is found to be wrong.

I think that sort of display tends to discourage people from seeking the
truth. It also injects ego (doesn't matter on whose side) into this. It may
or may not become obvious that your or my theory is wrong. If it does, I
think that the goal has been accomplished: New knowledge!

We're both operating in good faith here, as far as I can tell, re trying to
explain a technical phenomenon.

I don't have confidence that the experts at BoltScience will be able to
address this problem adequately, but I'll hear out whatever response they
have. I do think their site is pretty good, though, for general bolt
information purposes.

I would be more interested in what Honda Company says about the material.

You already answered it, for the greater part, earlier. I checked it. (It's
a bit of guesstimating, as I think you're aware, because that's the nature
of much engineering/technology.) It sounds like Bozo is capable of
discussing this further, with numbers, as well. Jim may be acquainted with
bolt stress calculations, too.

The stress achieved in a 14 mm nominal diameter/1.25 pitch bolt (typical
pulley bolt for many Hondas) torqued to 300 ft-lbs is darn near the ultimate
tensile strength of Grade 8 (or for metric, 10.9) steel. Never mind
exceeding the elastic strength (though this may be close to the ultimate
strength for this bolt material)...

Now I don't buy rust per se getting in there at all; based on the location;
the appearance of my own pulley bolt; and Jim's observations of how quickly
the bolt tightens after driving.

All told, these realities make me think that maybe the bolt material, under
high stress and at high temperatures, is, over time, being melded with the
metal of the crankshaft. That "crack" sound and the dust rising feed into
this a bit. (OTOH, it's a helluva lot of torque needed to break the bolt
free. I have heard smaller cracks with smaller bolts.)

Maybe this "melding" is what people have in mind when they talk about "heat
cycling" of the bolt.

But then on the third hand I would think the head of that pulley bolt would
shear off the way the heads of some of the suspension bolts so readily do
when it's being torqued to free it. The suspension bolts are only 10 mm
IIRC, but still, it doesn't take much torque at all to tear off one of their
heads.

My two cents again: The work of physicists is more black and white than
engineers' and technicians'. Indeed, I imagine he'd have a huge hurdle to
overcome with the reality that torque on real bolts rarely correlates to a
precise axial load. S I wouldn't look at this person as an authority.

I would trust BoltScience people a lot more, but still have doubts they can
take the time to really study what's behind this high torque needed to
remove the Honda pulley bolt.

Well they don't seem to be labeled "special bolt" at the www.slhonda.com and
in the manuals the way the pulley bolt is. I was looking at my 91 Civic's
suspension bolts at www.slhonda.com earlier, to see if they're as expensive
as the pulley bolt (at about $6). Some are. They're longer, but they also
have splines on them. As you note below.

I agree that there are bolts that have "special" applications though, and
are accordingly spec'd by Honda and then purchased from a bolt manufacturer.

Do you know this based on trying to drill/saw these recently?

I am sure you're right, but it's based only on my own attempts to drill/saw
them.

On my pulley holder tool, before I was tuned into the differences between
pulleys, and so before I used the hose as a spacer, I actually bent a Grade
8 bolt trying to get the thing to work. I had to buy a third one. This to me
is evidence (imprecise, but ballpark) of what kind of forces we're talking
about being applied to the pulley bolt when we try to free it. It's
stunning, IMO, that one rarely, if ever, reads of pulley bolts being damaged
during the removal process. Now why is that? Like you, I can't believe it's
made of something stronger than 10.9. And yet...

So I don't know. Oughta grab one from the junkyard and have it tested
somewhere. I wish I had hope Honda Company would respond to a query like
this, but I don't know that they would, for a few reasons.

Car Talk's Tom and Ray might entertain it. (I recall you're not wild about
them, but I think they're honest and say when they don't know.)

Agreed.

 

True. There must be lofty (and valid) explanations of why certain exhaust
bolts are so tough to remove after years of operation. I wouldn't buy that
it's just rust. (So far though PB Blaster has dealt with all the exhaust
bolts I've needed to free just fine.) Chemical action between the bolt metal
and the female side, abetted by heat? Whatever minerals (or whatever) are on
the threads at the start have the potential to thoroughly seize the bolt up
at high temperatures?

Just checked the parts site and I see one of the exhaust bolts is called a
"special bolt" too.

I suppose "special" may be a 10.9 designator. Or it's a fine thread
designator, since the 91 Civic's pulley bolt is 14 mm/1.25 mm pitch. The
standard fine thread pitch for a 14 mm nominal diameter bolt is 1.5 mm.

The exhaust "special bolt" is a fine thread, but a standard one.

I don't want to drag you into an online battle.

 

Looked it over. You've drug a whole Usenet battle unrelated to the goal of
fixing Hondas onto your site.

I don't support Jim's precession theory.

You have not represented my position accurately.

You did much more than you said you were going to do.

You're frustrated. I'm annoyed. I don't want my site linked to yours.

But I remain happy to agree to disagree, FWIW.