|
Re: Mystery Nut--Anyone Identify?
"Eric" <say.no@spam.now> wrote in message news:446BA0CF.769AAC7A@spam.now... > "TeGGeR®" wrote: >> >> Matt Ion <soundy@moltenimage.com> wrote in >> news:rXIag.172150$WI1.82189@pd7tw2no: >> >> > Elle wrote: >> >> Can anyone please identify the nut pictured at the >> >> following >> >> site? >> >> >> >> http://home.earthlink.net/~honda.lioness/id16.html >> > >> > That would be TeGGeR... oh wait, wrong picture ;) >> >> Whaaaat? I resemble that remark. >:^Þ >> >> It's an exhaust manifold nut. Looks like part of the >> stud is still in it >> too, so that's broken. >> >> Remove the front heat shield for the exhaust manifold and >> have a look at >> all the studs. >> > > I also thought it looked like an exhaust manifold nut. > The question remains > though, how did it get under the dash? Was Elle under the > dash recently and > unknowingly transferred the nut there? No; miscommunication. My Civic was on ramps, and I was under the car, grinding out one of the control arm bolts, for a long time (see other thread). About mid-day I moved the cardboard and wood planks on which I lie for this sort of work and found this lock-nut (with, as Tegger said, part of a stud attached). I figured the grinding vibrations knocked it free. I'll get a closer look tomorrow. Car's driving okay, all things considered (especially all my monkeying with everything). Thanks, folks, this will save me a lot of time. |
Re: Mystery Nut--Anyone Identify?
"Eric" <say.no@spam.now> wrote in message news:446BA0CF.769AAC7A@spam.now... > "TeGGeR®" wrote: >> >> Matt Ion <soundy@moltenimage.com> wrote in >> news:rXIag.172150$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 ;) >> >> 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. >> > > 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? 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. |
Re: Mystery Nut--Anyone Identify?
"Eric" <say.no@spam.now> wrote in message news:446BA0CF.769AAC7A@spam.now... > "TeGGeR®" wrote: >> >> Matt Ion <soundy@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 ;) >> >> 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. >> > > 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? 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. |
Re: Mystery Nut--Anyone Identify?
<ah1244@wayne.edu> wrote
> >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. |
Re: Mystery Nut--Anyone Identify?
<ah1244@wayne.edu> wrote
> >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. |
Re: Mystery Nut--Anyone Identify?
<ah1244@wayne.edu> wrote
> >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. |
Re: Mystery Nut--Anyone Identify?
Elle wrote:
> > 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 |
Re: Mystery Nut--Anyone Identify?
Elle wrote:
> > 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 |
Re: Mystery Nut--Anyone Identify?
Elle wrote:
> > 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 |
Re: Mystery Nut--Anyone Identify?
Hello: I just checked the stud/nut diameters with a caliper after your
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. |
Re: Mystery Nut--Anyone Identify?
Hello: I just checked the stud/nut diameters with a caliper after your
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. |
Re: Mystery Nut--Anyone Identify?
Hello: I just checked the stud/nut diameters with a caliper after your
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. |
Re: Mystery Nut--Anyone Identify?
<ah1244@wayne.edu> wrote in message
news:1147919073.679969.107510@j33g2000cwa.googlegr oups.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...... > That's what it looks like to me - a high-temperature locking nut. Mike |
Re: Mystery Nut--Anyone Identify?
<ah1244@wayne.edu> wrote in message
news:1147919073.679969.107510@j33g2000cwa.googlegr oups.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...... > That's what it looks like to me - a high-temperature locking nut. Mike |
Re: Mystery Nut--Anyone Identify?
<ah1244@wayne.edu> wrote in message
news:1147919073.679969.107510@j33g2000cwa.googlegr oups.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...... > That's what it looks like to me - a high-temperature locking nut. Mike |
Re: Mystery Nut--Anyone Identify?
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! 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. |
Re: Mystery Nut--Anyone Identify?
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! 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. |
Re: Mystery Nut--Anyone Identify?
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! 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. |
Re: Mystery Nut--Anyone Identify?
"Elle" <honda.lioness@nospam.earthlink.net> wrote in
news:hIkbg.4307$y4.4095@newsread2.news.pas.earthli nk.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® The Unofficial Honda/Acura FAQ www.tegger.com/hondafaq/ |
Re: Mystery Nut--Anyone Identify?
"Elle" <honda.lioness@nospam.earthlink.net> wrote in
news:hIkbg.4307$y4.4095@newsread2.news.pas.earthli nk.net: > I took the exhaust manifold shroud off today. It is indeed > an exhaust manifold nut (with broken-off stud stuck in it). > It's the one nearest the distributor. > > I am amazed at how many people (Nasty, Tegger, Eric, > SoCalMike) nailed this, and with a fuzzy photo, too. What a > phenomenal newsgroup! Broken studs are very common. I had one too. Mine broke below the surface of the head. My mechanic removed it, but wouldn't tell me how (trade secret, or so he says...). It was done at the same time as my head gasket replacement, so the machine shop that trued the head probably did it. The problem is that exhaust pulses are quite violent. This is the reason you need heat-resistant "prevailing torque" nuts. The nuts don't vibrate off, but the pulses often break a stud. Funny, the one that broke on mine was the one nearest the timing belt. It must be a random thing. -- TeGGeR® The Unofficial Honda/Acura FAQ www.tegger.com/hondafaq/ |
Re: Mystery Nut--Anyone Identify?
"Elle" <honda.lioness@nospam.earthlink.net> wrote in
news:hIkbg.4307$y4.4095@newsread2.news.pas.earthli nk.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® The Unofficial Honda/Acura FAQ www.tegger.com/hondafaq/ |
Re: Mystery Nut--Anyone Identify?
"TeGGeR®" <tegger@tegger.c0m> wrote in
news:Xns97C8D2ABBFBEtegger@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... -- TeGGeR® The Unofficial Honda/Acura FAQ www.tegger.com/hondafaq/ |
Re: Mystery Nut--Anyone Identify?
"TeGGeR®" <tegger@tegger.c0m> wrote in
news:Xns97C8D2ABBFBEtegger@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... -- TeGGeR® The Unofficial Honda/Acura FAQ www.tegger.com/hondafaq/ |
Re: Mystery Nut--Anyone Identify?
"TeGGeR®" <tegger@tegger.c0m> wrote in
news:Xns97C8D2ABBFBEtegger@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... -- TeGGeR® The Unofficial Honda/Acura FAQ www.tegger.com/hondafaq/ |
Re: Mystery Nut--Anyone Identify?
"TeGGeR®" <tegger@tegger.c0m> wrote
> "Elle" <honda.lioness@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. |
Re: Mystery Nut--Anyone Identify?
"TeGGeR®" <tegger@tegger.c0m> wrote
> "Elle" <honda.lioness@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. |
Re: Mystery Nut--Anyone Identify?
"TeGGeR®" <tegger@tegger.c0m> wrote
> "Elle" <honda.lioness@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. |
Exhaust Manifold Stud Replacement Questions [was Re: Mystery Nut--Anyone Identify?]
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. 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. |
Exhaust Manifold Stud Replacement Questions [was Re: Mystery Nut--Anyone Identify?]
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. 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. |
Exhaust Manifold Stud Replacement Questions [was Re: Mystery Nut--Anyone Identify?]
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. 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. |
Re: Exhaust Manifold Stud Replacement Questions [was Re: MysteryNut--Anyone Identify?]
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?? > I am pricing a new exhaust manifold gasket, studs, and nuts > locally today. |
Re: Exhaust Manifold Stud Replacement Questions [was Re: MysteryNut--Anyone Identify?]
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?? > I am pricing a new exhaust manifold gasket, studs, and nuts > locally today. |
Re: Exhaust Manifold Stud Replacement Questions [was Re: MysteryNut--Anyone Identify?]
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?? > I am pricing a new exhaust manifold gasket, studs, and nuts > locally today. |
Re: Exhaust Manifold Stud Replacement Questions [was Re: Mystery Nut--Anyone Identify?]
"Grumpy AuContraire" <Grumpster@GrumpyvilleNOT.com> wrote
> 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. 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). |
Re: Exhaust Manifold Stud Replacement Questions [was Re: Mystery Nut--Anyone Identify?]
"Grumpy AuContraire" <Grumpster@GrumpyvilleNOT.com> wrote
> 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. 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). |
Re: Exhaust Manifold Stud Replacement Questions [was Re: Mystery Nut--Anyone Identify?]
"Grumpy AuContraire" <Grumpster@GrumpyvilleNOT.com> wrote
> 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. 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). |
Re: Exhaust Manifold Stud Replacement Questions [was Re: MysteryNut--Anyone Identify?]
Elle wrote: > > "Grumpy AuContraire" <Grumpster@GrumpyvilleNOT.com> wrote > > 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. > > 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). 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 |
Re: Exhaust Manifold Stud Replacement Questions [was Re: MysteryNut--Anyone Identify?]
Elle wrote: > > "Grumpy AuContraire" <Grumpster@GrumpyvilleNOT.com> wrote > > 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. > > 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). 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 |
Re: Exhaust Manifold Stud Replacement Questions [was Re: MysteryNut--Anyone Identify?]
Elle wrote: > > "Grumpy AuContraire" <Grumpster@GrumpyvilleNOT.com> wrote > > 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. > > 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). 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 |
Re: Exhaust Manifold Stud Replacement Questions [was Re: MysteryNut--Anyone Identify?]
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. 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". |
| All times are GMT -4. The time now is 07:36 AM. |
© 2024 MH Sub I, LLC dba Internet Brands