Mystery Nut--Anyone Identify?
Elle
site?
http://home.earthlink.net/~honda.lioness/id16.html
It's head is 12 mm across. It has some sort of locking
mechanism. It sheared off its stud, presumably due to age
and the vibrations that resulted while I was grinding off
the lower inboard control arm bolt on the driver's side.
Part of the stud appears in the photo. At the end of the
day, I found it beneath the cardboard on which I lie to do
this work.
I will be inspecting the engine compartment to see if I can
see a similar one.
RWM
notbob
> Can anyone please identify the nut pictured at the following
> site?
Can you identify the nut who took this terrible picture? As blurry as
this photograph is, it's most likely to remain a mystery, though I'd
venture a wild guess at a nylon-self-locking nut.
> It's head is 12 mm across. It has some sort of locking
> mechanism. It sheared off its stud, presumably due to age
> and the vibrations that resulted while I was grinding off
> the lower inboard control arm bolt on the driver's side.
> Part of the stud appears in the photo. At the end of the
> day, I found it beneath the cardboard on which I lie to do
> this work.
Did you shear this nut off yourself or just find it? Are you sure
it's not really a old metal tire valve stem cap?
nb
Curly Q. Links
>
> Can anyone please identify the nut pictured at the following
> site?
>
> http://home.earthlink.net/~honda.lioness/id16.html
-------------------------------
I think it's an out-of-focus picture of one of them alien space craft
that they used to publish back in the 70's. Looks a bit taller though
:-(
Tip: On digital cameras that don't have a MACRO or close-up setting, you
can hold a magnifying glass or Grandpa's reading glasses in front of the
lens, and it works just fine.
'Curly'
Nasty
to me. On my '00 Accord both the intake and exhaust are 12mm.
"Elle" <honda....@nospam.earthlink.net> wrote in message
news:mbFag.83$SX5...@newsread1.news.pas.earthlink.net...
Elle
suggestion. My Chilton's does indeed show a bunch of exhaust
and intake manifold nuts that seem to fit the bill.
Majestic's online parts site confirms that the exhaust
manifold has nine self-locking nuts. It's also certainly
rusted enough that I would expect it to be either in a
weather path or on the exhaust system somewhere. I'll take
the shroud off tomorrow and confirm. Thank you!
Curly, good tip. I know it's a lousy photo.
RWM, it's some kind of self-locking nut and so is a little
unique looking. I thought someone might recognize it before,
ya know, I discover the hard way and my engine falls apart
or something on the highway later today.
"Nasty" <nastym...@tampabay.rr.com> wrote
Grumpy AuContraire
locking insurance.
JT
Grumpy AuContraire
"'Curly Q. Links'" wrote:
>
snip
>
> Tip: On digital cameras that don't have a MACRO or close-up setting, you
> can hold a magnifying glass or Grandpa's reading glasses in front of the
> lens, and it works just fine.
>
> 'Curly'
That quite a tip Curly... Who would have known???
I'll pass that onn to my cheap friends who have cheap cameras!
JT
(Yep, you can learn something new every day)
Matt Ion
> Can anyone please identify the nut pictured at the following
> site?
>
> http://home.earthlink.net/~honda.lioness/id16.html
That would be TeGGeR... oh wait, wrong picture ;)
> It's head is 12 mm across. It has some sort of locking
> mechanism. It sheared off its stud, presumably due to age
> and the vibrations that resulted while I was grinding off
> the lower inboard control arm bolt on the driver's side.
> Part of the stud appears in the photo. At the end of the
> day, I found it beneath the cardboard on which I lie to do
> this work.
>
> I will be inspecting the engine compartment to see if I can
> see a similar one.
Do you have a pic that's not quite so fuzzy?
---
avast! Antivirus: Outbound message clean.
Virus Database (VPS): 0620-1, 05/17/2006
Tested on: 5/17/2006 10:20:23 AM
avast! - copyright (c) 1988-2006 ALWIL Software.
http://www.avast.com
Elle
> Elle wrote:
>> Can anyone please identify the nut pictured at the
>> following site?
>>
>> http://home.earthlink.net/~honda.lioness/id16.html
>
> That would be TeGGeR... oh wait, wrong picture ;)
Ha. We're all gearheads in this together. :-)
> Do you have a pic that's not quite so fuzzy?
I'm afraid not. I am looking for a magnifying glass. Little
busy today.
TeGGeR®
news:rXIag.172150$WI1.82189@pd7tw2no:
> Elle wrote:
>> Can anyone please identify the nut pictured at the following
>> site?
>>
>> http://home.earthlink.net/~honda.lioness/id16.html
>
> That would be TeGGeR... oh wait, wrong picture ;)
Whaaaat? I resemble that remark. >:^Þ
It's an exhaust manifold nut. Looks like part of the stud is still in it
too, so that's broken.
Remove the front heat shield for the exhaust manifold and have a look at
all the studs.
--
TeGGeR®
The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/
Eric
>
> Matt Ion <sou...@moltenimage.com> wrote in
> news:rXIag.172150$WI1.82189@pd7tw2no:
>
> > Elle wrote:
> >> Can anyone please identify the nut pictured at the following
> >> site?
> >>
> >> http://home.earthlink.net/~honda.lioness/id16.html
> >
> > That would be TeGGeR... oh wait, wrong picture ;)
>
>
> It's an exhaust manifold nut. Looks like part of the stud is still in it
> too, so that's broken.
>
> Remove the front heat shield for the exhaust manifold and have a look at
> all the studs.
>
I also thought it looked like an exhaust manifold nut. The question remains
though, how did it get under the dash? Was Elle under the dash recently and
unknowingly transferred the nut there?
Eric
SoCalMike
i would put money on it being a stud/nut for the exhaust system. either
the a/b/c pipes, the catalyst, or possibly the exhaust manifold. its got
the same patina of a nut/stud thats been in high heat all its life.
ah1...@wayne.edu
nuts from the front suspension. There are 4 identical sized nuts (all
12x1.25 mm) but with different torque settings (page 18-8 of service
manual; 1991 Civic). One on top of the strut housing, and two at the
bottom, and another one at the end of the control arm. If you need the
diagram, do drop a line, and I will scan the page and send it over.
Hope this helps......
Elle
"Eric" <say...@spam.now> wrote in message
news:446BA0CF...@spam.now...
No; miscommunication. My Civic was on ramps, and I was under
the car, grinding out one of the control arm bolts, for a
long time (see other thread). About mid-day I moved the
cardboard and wood planks on which I lie for this sort of
work and found this lock-nut (with, as Tegger said, part of
a stud attached). I figured the grinding vibrations knocked
it free.
I'll get a closer look tomorrow. Car's driving okay, all
things considered (especially all my monkeying with
everything).
Thanks, folks, this will save me a lot of time.
Elle
> >From that photo, looks like one of those Castle nuts or
> >Self-locking
> nuts from the front suspension. There are 4 identical
> sized nuts (all
> 12x1.25 mm)
Is that 12 mm the nominal diamter of the suspension bolts
onto which these suspension self-locking nuts fit, though?
That sounds more likely.
The 12 mm I mention for this mystery nut is the nut head
measurement. That is, a 12 mm socket fits it. The nominal
diameter of its corresponding stud appears to be 6 mm or 8
mm. (The stud diameter is a little hard to measure while
it's stuck in the nut.)
Thanks for the input. I'll update tomorrow, hopefully.
Eric
>
> Is that 12 mm the nominal diamter of the suspension bolts
> onto which these suspension self-locking nuts fit, though?
> That sounds more likely.
>
> The 12 mm I mention for this mystery nut is the nut head
> measurement. That is, a 12 mm socket fits it. The nominal
> diameter of its corresponding stud appears to be 6 mm or 8
> mm. (The stud diameter is a little hard to measure while
> it's stuck in the nut.)
>
Most 12 mm nuts on a Honda are threaded for an 8 x 1.25 mm bolt.
Eric
ah1...@wayne.edu
and Elle's posts. Yes, you two are correct: the 12x1.25 mm that Honda
manual refers to is the stud diameter and not the nut diameter (should
have remembered this...my apologies). For the 12 mm diameter nut Elle
refers to, looks like the corresponding stud size is 8 mmx1.25 mm as
Eric correctly suggests. If yours came from the front suspension, there
is just one such self-locking-nut according to the front suspension
diagram; 8x1.25 mm, stabilizer bar /lower arm attachment. According to
the diagram, in the front suspension, there are
6 of 12x1.25 mm self-locking/castle nuts (missed two of these in my
earlier post!)
5 of 10x1.25 mm
1 of 8x1.25 mm; all self-locking or castle nuts. As Eric and you
indicate correctly, the 12, 10 or 8 referred to in the diagram are for
the stud diameter.
Michael Pardee
news:1147919073.6...@j33g2000cwa.googlegroups.com...
> >From that photo, looks like one of those Castle nuts or Self-locking
> nuts from the front suspension. There are 4 identical sized nuts (all
> 12x1.25 mm) but with different torque settings (page 18-8 of service
> manual; 1991 Civic). One on top of the strut housing, and two at the
> bottom, and another one at the end of the control arm. If you need the
> diagram, do drop a line, and I will scan the page and send it over.
> Hope this helps......
>
Mike
Elle
an exhaust manifold nut (with broken-off stud stuck in it).
It's the one nearest the distributor.
I am amazed at how many people (Nasty, Tegger, Eric,
SoCalMike) nailed this, and with a fuzzy photo, too. What a
phenomenal newsgroup!
I see the stud on sale at Majestic online for a couple
bucks.
I reckon I'll see how my ball joint castle nut/stud work
goes today and then make a trip to the junkyard. I think the
front desk man and I could become an item... :-)
Much obliged for everyone's input. This all is valued work
to me, and I couldn't do it nearly as efficiently (and at
some points, not at all) without the extensive experience of
so many of you.
TeGGeR®
news:hIkbg.4307$y4....@newsread2.news.pas.earthlink.net:
> I took the exhaust manifold shroud off today. It is indeed
> an exhaust manifold nut (with broken-off stud stuck in it).
> It's the one nearest the distributor.
>
> I am amazed at how many people (Nasty, Tegger, Eric,
> SoCalMike) nailed this, and with a fuzzy photo, too. What a
> phenomenal newsgroup!
Broken studs are very common. I had one too. Mine broke below the surface
of the head. My mechanic removed it, but wouldn't tell me how (trade
secret, or so he says...). It was done at the same time as my head gasket
replacement, so the machine shop that trued the head probably did it.
The problem is that exhaust pulses are quite violent. This is the reason
you need heat-resistant "prevailing torque" nuts. The nuts don't vibrate
off, but the pulses often break a stud.
Funny, the one that broke on mine was the one nearest the timing belt. It
must be a random thing.
TeGGeR®
news:Xns97C8D2A...@207.14.116.130:
>
> The problem is that exhaust pulses are quite violent. This is the
> reason you need heat-resistant "prevailing torque" nuts. The nuts
> don't vibrate off, but the pulses often break a stud.
That combined with the exhaust system flexing as the engine torques on its
mounts, of course...
Elle
> "Elle" <honda....@nospam.earthlink.net> wrote
>> I took the exhaust manifold shroud off today. It is
>> indeed
>> an exhaust manifold nut (with broken-off stud stuck in
>> it).
>> It's the one nearest the distributor.
>>
>> I am amazed at how many people (Nasty, Tegger, Eric,
>> SoCalMike) nailed this, and with a fuzzy photo, too. What
>> a
>> phenomenal newsgroup!
>
>
>
> Broken studs are very common. I had one too. Mine broke
> below the surface
> of the head. My mechanic removed it, but wouldn't tell me
> how (trade
> secret, or so he says...). It was done at the same time as
> my head gasket
> replacement, so the machine shop that trued the head
> probably did it.
Mine is broken off at the outer surface of the exhaust
manifold. Hopefully "all" I have to do is remove the
manifold, and I'll plenty of leftover stud to
drill/double-nut/etc.
I'm not going to pursue it until I get my new front lower
control arm bushings in (knock on wood). Tomorrow's a big
day.
Doggone Napa said they had the stud. I go there and they
insist it's a 10 mm stud. I didn't have the broken nut-stud
with me and bought it. Back I go.
> The problem is that exhaust pulses are quite violent. This
> is the reason
> you need heat-resistant "prevailing torque" nuts. The nuts
> don't vibrate
> off, but the pulses often break a stud.
>
> Funny, the one that broke on mine was the one nearest the
> timing belt. It
> must be a random thing.
Interesting. Maybe I'll see about replacing all nine or so,
before they break within the cylinder head.
Thanks for the info. As always, it's very helpful.
Elle
(91 Civic LX, 176k miles) when installing it in the cylinder
head? This torque specification does not seem to appear in
the service manual or my Chilton's.
I see the locking nuts get 23 ft-lbs, so I suppose that's
reasonable for the studs, too. Still, perhaps someone here
has some more insight or thoughts on what is reasonable
here.
Also, ISTM I should replace all nine studs. Any good reason
not to? "If it ain't broke, don't fix it," is a good rule,
but on a car this old, and since broken exhaust manifold
studs are fairly common, I think an ounce of prevention may
be appropriate here. Your experience on this matter is
welcome.
I plan to double nut the studs to remove them, being mindful
that they are fatigued and could very well break off in an
undesirable way.
Again, they're 8 mm nominal diameter studs.
My Civic yesterday recorded the lowest gas mileage since I
started keeping careful records two years ago--36.3 mpg vs.
my average of about 40 mpg (higher in late spring and
summer). It's never been this low for this time of year. I
googled and it certainly seems that the missing nut may be
causing an exhaust leak and causing the engine control
system to run rich.
I am pricing a new exhaust manifold gasket, studs, and nuts
locally today.
Grumpy AuContraire
Elle wrote:
>
> What torque should be applied to the exhaust manifold stud
> (91 Civic LX, 176k miles) when installing it in the cylinder
> head? This torque specification does not seem to appear in
> the service manual or my Chilton's.
>
> I see the locking nuts get 23 ft-lbs, so I suppose that's
> reasonable for the studs, too. Still, perhaps someone here
> has some more insight or thoughts on what is reasonable
> here.
>
Studs should have slightly more torque than nuts as it is desired that
the nut turn freely (when loosening) while the stud remains in place.
this can be done by locking two nuts together when installing the stud.
Using "lock tight" is also a possibility but may not be as effective due
to the high heat this application must endure.
> Also, ISTM I should replace all nine studs. Any good reason
> not to? "If it ain't broke, don't fix it," is a good rule,
> but on a car this old, and since broken exhaust manifold
> studs are fairly common, I think an ounce of prevention may
> be appropriate here. Your experience on this matter is
> welcome.
>
Yes, I would replace all of 'em if it is not a big hassle.
> I plan to double nut the studs to remove them, being mindful
> that they are fatigued and could very well break off in an
> undesirable way.
>
That's ok. Just be patient and work the studs in both directions to
gradually loosen 'em up. Also, a direct blow or two to the top of the
stud itself can be beneficial. Just make sure a nut is present to
protect the threads.
> Again, they're 8 mm nominal diameter studs.
>
> My Civic yesterday recorded the lowest gas mileage since I
> started keeping careful records two years ago--36.3 mpg vs.
> my average of about 40 mpg (higher in late spring and
> summer). It's never been this low for this time of year. I
> googled and it certainly seems that the missing nut may be
> causing an exhaust leak and causing the engine control
> system to run rich.
>
Ethanol mix maybe??
Elle
Sounds good. My parts are on order locally and I think I'll
work on this before my pass. side front bushings. I'm going
to soak as much as I can of the applicable bolt threads in
PB Blaster today. Fortunately I had the header pipe
disconnected from the exhaust manifold a couple of years
ago.
Thanks for sharing your experience, JT.
>> Again, they're 8 mm nominal diameter studs.
>>
>> My Civic yesterday recorded the lowest gas mileage since
>> I
>> started keeping careful records two years ago--36.3 mpg
>> vs.
>> my average of about 40 mpg (higher in late spring and
>> summer). It's never been this low for this time of year.
>> I
>> googled and it certainly seems that the missing nut may
>> be
>> causing an exhaust leak and causing the engine control
>> system to run rich.
>>
>
> Ethanol mix maybe??
No. I am using the same gas stations I usually use. They
haven't shifted. Last time I did get a winter mix, I didn't
notice a change in fuel mileage (using odometer
miles/gallons added to top off).
Grumpy AuContraire
I think that all gasoline sold nationally now has to have an ethanol
content of 10% that replaces MBTE (sp?) that was declared "dangerous" by
the EPA.. There was a big fuss by the oil companies and refiners.
JT
SoCalMike
> What torque should be applied to the exhaust manifold stud
> (91 Civic LX, 176k miles) when installing it in the cylinder
> head? This torque specification does not seem to appear in
> the service manual or my Chilton's.
AFAIK, they basically just thread all the way (half way?) in, and thats
it. no torque necessary. when you attach the nut and washer, and torque
*that* it tightens the stud as well, or at least causes the stud to
become "elastic".
TeGGeR®
news:oqCdnSJZjp0...@comcast.com:
I suspect you're right. Just tighten until it bottoms, then stop.
I just checked several factory manuals here, and not one specifies a torque
figure for the studs.
Stephen H
I have 2 4 piece sets of these (the picture doesn't show the bottom) It has
3 cams that roll out and pinch the stud for removal and installation. It
sometime leaves small dimples in the stud but has never effected the
operation. Check Sears, Harbor freight. Saves tones of time on studs. (i.e.,
threading two nuts on, having them slip, re tighten, remove stud now try to
remove the nuts for the next go-around.
http://www.bugsandbuggies.com/Parts.asp?CN=626&SN=67&GN=9
--
Stephen W. Hansen
ASE Certified Master Automobile Technician
ASE Automobile Advanced Engine Performance
ASE Undercar Specialist
http://autorepair.about.com/cs/troubleshooting/l/bl_obd_main.htm
http://www.troublecodes.net/technical/
http://www.familycar.com/Alignment.htm
TeGGeR®
news:RnScg.92413$Fs1....@bgtnsc05-news.ops.worldnet.att.net:
> Elle,
> I have 2 4 piece sets of these (the picture doesn't show the bottom)
> It has
> 3 cams that roll out and pinch the stud for removal and installation.
> It sometime leaves small dimples in the stud but has never effected
> the operation. Check Sears, Harbor freight. Saves tones of time on
> studs. (i.e., threading two nuts on, having them slip, re tighten,
> remove stud now try to remove the nuts for the next go-around.
Now what do you do for studs that have broken off flush with the head or
below?
Elle
locally "stud removal sockets." I just checked Ebay and
found a few (and just a few) similar kits. For others who
are interested, the bottom of one such set is partly shown
at
http://cgi.ebay.com/4-PC-STUD-PULLER-REMOVER-WRENCH-METRIC-SIZES-AUTO_W0QQitemZ4464730279QQcategoryZ50379QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
I also googled on this topic yesterday. The only site that
seemed helpful (so far) is
http://www.swedishbricks.net/700900FAQ/Exhaust1.html#Exhaust%20Manifold%20Gasket%20&%20Studs%20Replacement .
There is indeed a mention of a "locking collar type stud
remover." On first reading, that went right by me. It's
surely the tool you suggest, though.
Tegger, for studs that are broken off flush with the
cylinder head, several folks at this site make a strong
argument (based in experience) for right angle (and
reversible) drills.
Aside: I was at Harbor Freight yesterday. Fifteen dollars
buys a lot of tools which show, to me, great promise for
making my bushing replacement efforts easier when I go at
the passenger side lower control arm in a day or so. Air
hammer (seven bucks), tiny 3/4-inch diameter diamond mini
cutting discs (for my air die grinder), tiny wire brush for
a low RPM electric drill. I'm frugal, but I kept thinking,
for two or so bucks more, this or that might save me five
hours and a lot of sore muscles, keep me safer, etc.
I go at the exhaust manifold studs maybe next week.
"Stephen H" <hans...@hotmail.com> wrote
Stephen H
Drill it open, insert the easy our and try; sometimes the heat of the drill
breaks it loose, but be careful, you don't want to break the easy out. If
that doesn't do the trick, an ox/ace torch, heat the stud hot and then try.
--
Stephen W. Hansen
ASE Certified Master Automobile Technician
ASE Automobile Advanced Engine Performance
ASE Undercar Specialist
http://autorepair.about.com/cs/troubleshooting/l/bl_obd_main.htm
http://www.troublecodes.net/technical/
http://www.familycar.com/Alignment.htm
"TeGGeR®" <teg...@tegger.c0m> wrote in message
news:Xns97CD4CF7...@207.14.116.130...
Elle
socket (with the roller cams) on Ebay for $13 ($7 + $6
shipping). Over the past two weeks, and after driving the
car awhile so the engine was hot, I removed the old nuts and
applied PB Blaster so as to maybe penetrate to the studs'
threads. The stud removal socket worked perfectly on all
nine studs, including the one partly broken off. Enough stub
was left so
that it was not a problem.
Very little torque was required to remove the studs with the
socket. I needed only an ordinary 8-inch ratchet with a
little pressure applied. It seemed they might have still
been
tightened to the 23 ft-lbs specification applied at
the factory some 15 years ago! The old studs were very
clean, and all threads were in good shape. Nonetheless since
they were surely fatigued
from cyclic heating and cooling and vibrations, I replaced
both studs and nuts.
The original exhaust manifold gasket is a three-layered,
aluminum like affair, with the layer nearest the engine
having webs. The new gasket I bought is a single layer, no
webs. Dunno what's up with this. I retained the first two
layers and replaced the layer furthest from the engine,
since it looked most like the new gasket.
The three manifold-to-header-pipe stud threads are in
questionable shape at this time, from the two times now I've
applied serious torque. I'll chase them down soon and
possibly replace them.
Fortunately th was a very easy job.
Test drive was fine. With every control arm bushing set I
replace, I think the handling is improving. I think it is
worth the effort I am putting into it.
Little aside: I previously reported a seeming drop in fuel
mileage (to 36.3 mpg, a record low in the last few years)
after the one exhaust manifold stud broke. On the next tank,
the fuel mileage shot up to 47.8 mpg (a record high in the
last few years). So I think something was screwy during my
last two fill-ups. The average is close to my usual average
for this time of year.
I remain much obliged to people's input here. It's great to
learn and build, literally.