Help! Front Hub Bolt Removal Problem

I searched on here, didn't really find anything specific that applies. I'm in the process of replacing the front brakes with all new parts, including lines, hoses, calipers, rotors, pads, shields, bolts, the works. The reason for this is that this XJ came from New Hampshire and there is some serious rust damage. I got the left side done, really had no problems at all there, but the right side is another story. One of the bolt heads was rusty/crumbly.

The top hub bolt is really frozen in there, and the bolt head is now rounded off after I tried everything I could to get it loose. I even snapped a Bolt-Out socket in half, it still won't budge. I did use plenty of PB Blaster and let it soak for a day or two, knocked on it, the works, before I started trying to get it loose.

So, it looks like I'm down to removing the entire steering knuckle as a piece, and taking it somewhere to see if a shop can get it out. I'm thinking maybe a shop could weld another bolt onto the ruined head and get it out that way, or heat it, or something. Bearings and ball joints, etc., are all good, so I'd hate to have to replace the knuckle and hub. I don't have a welder or torch. I haven't removed the knuckle yet, so I don't know how hard that'll be either, but it'll be a couple of days before I can get to it.

So, in the meantime, if anyone has any ideas or suggestions or notes on how they solved this, I'm all ears. Help!!

Are you talking about the hub unit bearing screws? You DID use a 12-point 13m/m socket on those, right? A six-point will chew the corners off...

If they're really stuck on there, I'd see about getting a punch on the outside end (threaded end - you should be able to access it past the hub flange) and give it one or two good raps with a mallet - but no more. Shoot with PB Blaster before, smack it once or twice, and PB Blaster again (should be opened up a bit.)

If you can get a swing on the head (doubtful...) try smacking that once or twice (only!) as well. DO NOT beat on it - all you're trying to do is loosen it up, not drive it through the knuckle!

I seem to want to recall the screws are threaded M8-1.25, so you can probably match the underhead length, add washers, and use either socket heads or hex heads (your call) to replace any that are seriously buggered up.

An option (for the really crazed or really confident - I'd be loath to try it...) would be to drill the screw out from the outside until you get through the threaded part of the knuckle, then knock it out. I'd have to do some maths to make sure it would work, but I'm thinking it could probably be done with a 6m/m drill, or a 15/64" (or thereabouts.) I'd be seriously loath to use a full quarter-inch - you may end up damaging threads (metric equvalent to 1/4" is 6.3~m/m, IIRC - which may exceed the minor diameter of M8-1.25 threads slightly.) Centre punch, pilot drill, and work up to full size SLOWLY.

Theory would be that, once most of the centre of the screw shaft is removed, the threads should "pop" out of each other with some impact, and can be cleaned up using an M8-1.25 tap (CAREFULLY! You don't want to cross-thread...)

Hub bearing retainer screws are torqued to 75 pound-feet. If you use never-seez, torque to 37 pound-feet.

This is what's going through my mind when you say "hub bolt." If I'm wrong, please edify me so I can give you different advice (which you may find more useful...)

5-90, Yeah, that's the ones. Yup, I used the 12-pt. socket. The problem was the severe rust damage (as in crumbly). I did all those things, except drilling, which, from experience, I would never, ever do, unless I had no other choice. It doesn't work out well unless you have a machine shop, which I don't. You're probably a lot better than I am at "freehand" drilling, eh? I do, however, greatly appreciate your reply and ideas. I think I think a lot like you do in a lot of ways when it comes to "creative problem solving." You always seem to be one of the first, if not the first, to offer help. I hope everyone on this board appreciates that fact. I've only been a member here a short time, and you've already helped me out a couple of times. Thank you.

I do have one question. You mention different torque settings depending on whether or not I'm using anti-seize. Can you enlighten me on that? With all this rust I have to deal with on this thing, I'll be using a lot of it, so it would be handy information.

What I do have is the entire bolt still complete, only rounded off completely. Looks like I have to pull the steering knuckle off. I could put it in the vise and wail on it awhile, see if it'll come loose. But I could damage the threads that way too. My brother recommended vise grips and a big hammer. Another friend suggested a small pipe wrench instead of vise grips. I might give that a quick try, but last night I talked to the guys at the shop that repairs, maintains, and fuels my big truck. I think I'll just pull it off and take it down there. They have a fully equipped shop and lots of expertise. They will weld a nut onto the ruined bolt head and use that to get it out.

I'll report on how it went when it's done.

The small pipe wrench would be my best suggestion.

I love that tool

I know you said you tried a "bolt-out" socket, but was it a good quality one? I'd recommend a set of Craftsman damaged bolthead extractors..they work wonders. Try using one size smaller than what would fit on what's left of the bolthead and pound it on with a hammer. You might not be able to get it back off the bolt once it's out, but at least you'll get it out

Why are you pulling the hubs to do a brakejob anyhow? just to replace the dustsheild?? I have to remember the next time I have my hubs off to REMOVE the damn things completely. I almost ruined a good rotor one time when a piece of hot blacktop got stuck between that worthless sheild and the rotor face.

Jeff

kloker said:

5-90, Yeah, that's the ones. Yup, I used the 12-pt. socket. The problem was the severe rust damage (as in crumbly). I did all those things, except drilling, which, from experience, I would never, ever do, unless I had no other choice. It doesn't work out well unless you have a machine shop, which I don't. You're probably a lot better than I am at "freehand" drilling, eh? I do, however, greatly appreciate your reply and ideas. I think I think a lot like you do in a lot of ways when it comes to "creative problem solving." You always seem to be one of the first, if not the first, to offer help. I hope everyone on this board appreciates that fact. I've only been a member here a short time, and you've already helped me out a couple of times. Thank you.

I do have one question. You mention different torque settings depending on whether or not I'm using anti-seize. Can you enlighten me on that? With all this rust I have to deal with on this thing, I'll be using a lot of it, so it would be handy information.

What I do have is the entire bolt still complete, only rounded off completely. Looks like I have to pull the steering knuckle off. I could put it in the vise and wail on it awhile, see if it'll come loose. But I could damage the threads that way too. My brother recommended vise grips and a big hammer. Another friend suggested a small pipe wrench instead of vise grips. I might give that a quick try, but last night I talked to the guys at the shop that repairs, maintains, and fuels my big truck. I think I'll just pull it off and take it down there. They have a fully equipped shop and lots of expertise. They will weld a nut onto the ruined bolt head and use that to get it out.

I'll report on how it went when it's done.

Click to expand...

Anything that reduces the friction between the internal and external threads will significantly change the installed preload ("installation torque") of a threaded fastener. What you use will effect the amount of change in your installation preload.

Threaded fasteners, in the absence of some sort of chemical locking compount or a direct mechanical lock (deformed threads or Nylon collars/buttons,) depend upon the elasticity of the metal used to make the fastener to retain themselves. This also effects clamping force - which is why, for instance, installation torque on cylinder head and manifold screws is so important.

I've done tests at school comparing clamping force to installation torque (lubricated and dry, clean and dirty) and also installation using the "torque angle" method (where you turn the screw until it makes contact with the surface, then turn it a specified angle.) Short form of the results (bear in mind that, unless otherwise specified, torque values given in service literature are for "clean, dry" threads):
Using a torque wrench can vary installation preload by as much as +/- 15%!
Using some sort of "teflon paste" thread sealer (like used in plumbing) allows for the same tension on the fastener using ~10% less force (the carrier paste, apparently, makes up for most of the lubricity of the PTFE/Teflon.) Therefore, when using Teflon-based thread sealant paste (plumber's pipe dope, LocTite PST, or similar,) reduce installation torque by 10%.
Using engine oil or chassis grease as a lubricant reduces friction to where the same installed preload (tension on the fastener) is achieved using 1/4-1/3 less turning force (torque.) Therefore, if using engine oil or grease, reduce the given torque figure for "clean, dry" threads by 1/4 to 1/3 (I usually reduce by 1/3.)
Using some variety of anti-seize lubricant allows for the same installed tension using HALF of the turning force - reduce "clean, dry" torque figures by half. Note that this can also be done to "expand the capacity" of your torque wrench in some applications - the axle stub nut up front gets torqued to 175 pound-feet, or you can use never-seez and set your "clicker" for 87 pound-feet.
The use of threadlocker compounds (LocTite, e. g.) does not significantly affect installed tension using the torque method. Therefore, no changes to installed torque when using LocTite.
Lubricating threads actually will allow for more consistent installed preload when measuring the turning force to install the screw.
Using the "torque angle" method (when given the option,) will allow for even more consistency - even over lubricated and torqued screws! However, data is not always given (I should probably see about computing it one of these days...)
The effects of lubrication are minimal on "torque angle" fasteners, since you are measuring the angle through which the fastener is turned (60*, 90*, or 180* are most common) rather than the turning force. Ninety degrees is nintety degrees - lubricated or no. However, when using never-seez (for instance,) it will become possible to actually strip the threads right out of the mating part, or right off of the screw, if installing to full torque!

In summary -
When a "clean, dry" figure is given in the manual, reduce it by:
0% for "clean, dry" threads
0% for chemical locking compounds
10% when using some sort of Teflon paste compound (Teflon tape is not recommended)
30% when using engine oil or chassis grease
50% when using anti-seize lubricant.

Due to variations and manufacturing tolerances, the use of lubricants when not specified on critical fasteners (cylinder head screws, manifold screws, and most transmission and engine internals) is not RPT NOT recommended.

Cool! Thanks, 5-90. That should be a sticky in the Tech How-To Section I know is gonna be on here one of these days. Great information. Just goes to show that even on my 56th birthday (Say Happy Birthday, Larry!) I can still learn something new. I really never thought about this. 'Course, back in my racing days, in the 60's and 70's, I'd never heard of anti-seize.

Anyways, I won! I got the thing out,and all by myself, too. Duh! It didn't occur to me that if you can't get the hub off, you can't get the knuckle off either, the shaft is in the way! So, after I wasted an hour busting all those ball joints loose, I ended up deciding to hacksaw the bolt head off. It only took 30 minutes, once I figured out how to do it.

Once again, all I have to do is outsmart the cast iron. Once I got the hub off I had plenty of bolt shaft left to get hold of with the pipe wrench, and it came right out. Jeez, I should have just done that in the first place.

I already had the new shields, and I wanted to check on the bearings and clean up the whole rusty mess anyway, so that's why I pulled the hubs. I always seem to make it harder on myself by going farther than I need to, and end up creating a bunch of extra work to get it done. But, if or when I need to go back in there, it'll be easy next time. Like, if the shields give me problems, it'll be easy to get them off.

So now all I need to do is clean it all up and get it back together, and I have all brand new front brakes.

Next up, rear disk conversion. I've decided to go with ZJ parts, so I just have to scrounge all that up. When it's done, I'll have all new brakes all around, including all the lines. No more rust problems there.

Then it'll be lift and suspension time. After all this, I know that'll be a blast!

"Happy birthday, Larry!"

Seriously, tho, I've been working on a "fastener primer" for a little while myself - it's been through several working revisions, and I've mainly got to proofcheck it now and look up some sources to verify things I've known for years (but have long forgotten where I learned them.) It will get posted at WiP Tech, and will be available for FAQ use here as well. This will include the use of various thread compounds and the like - but I'll leave the heavy maths out unless it's specifically requested (things like converting wrench torque into fastener tension, for instance.)

I also intend to explain the uses of the two main SAE thread types (UNC and UNF,) but you're unlikely to run into any of the UNS thread pitches (8-, 12-, 18-, 24-series and the like - constant thread pitch over various sizes. Used with larger fasteners, mainly, and for mechanical power transmission.) And, I plan to discuss the more common thread forms as well.

It will probably be a "more than you ever wanted to know, and were definitely afraid to ask!" than anything else, but with some of the questions I've gotten offline, it's all stuff that I've felt a need to cover for some reason or another.

Which is why it's taking so long (I've been working on it for the last six months - ever since I got on my feet again - in between researching updates for The Power Manual, researches for Swappology, and trying - and failing, so far - to go back to school. Too much going on, and my brain is still rewiring itself. I tell you, brain injuries SUCK! At least I didn't lose as much as I could have...)

Not to worry - once I get something close to useable, I'll put out a call for about a half-dozen "beta readers," make revisions accordinly, and then I'll put it up somewhere. Rome wasn't built in a day...

kloker said:

Cool! Thanks, 5-90. That should be a sticky in the Tech How-To Section I know is gonna be on here one of these days. Great information. Just goes to show that even on my 56th birthday (Say Happy Birthday, Larry!) I can still learn something new. I really never thought about this. 'Course, back in my racing days, in the 60's and 70's, I'd never heard of anti-seize.

Anyways, I won! I got the thing out,and all by myself, too. Duh! It didn't occur to me that if you can't get the hub off, you can't get the knuckle off either, the shaft is in the way! So, after I wasted an hour busting all those ball joints loose, I ended up deciding to hacksaw the bolt head off. It only took 30 minutes, once I figured out how to do it.

Once again, all I have to do is outsmart the cast iron. Once I got the hub off I had plenty of bolt shaft left to get hold of with the pipe wrench, and it came right out. Jeez, I should have just done that in the first place.

I already had the new shields, and I wanted to check on the bearings and clean up the whole rusty mess anyway, so that's why I pulled the hubs. I always seem to make it harder on myself by going farther than I need to, and end up creating a bunch of extra work to get it done. But, if or when I need to go back in there, it'll be easy next time. Like, if the shields give me problems, it'll be easy to get them off.

So now all I need to do is clean it all up and get it back together, and I have all brand new front brakes.

Next up, rear disk conversion. I've decided to go with ZJ parts, so I just have to scrounge all that up. When it's done, I'll have all new brakes all around, including all the lines. No more rust problems there.

Then it'll be lift and suspension time. After all this, I know that'll be a blast!

Click to expand...

kloker said:

I already had the new shields, and I wanted to check on the bearings and clean up the whole rusty mess anyway, so that's why I pulled the hubs. I always seem to make it harder on myself by going farther than I need to, and end up creating a bunch of extra work to get it done. But, if or when I need to go back in there, it'll be easy next time. Like, if the shields give me problems, it'll be easy to get them off.

Click to expand...

Good times...glad you got it apart. I tend to obsess on things too...it's second nature dealing with a 20 yr old MJ, when fixing one thing it leads to freshening up about 5 other things connected to it.

Happy B-day, too! :cheers:

Jeff

You're lucky. My son has a 96 that spent some of its life by the seashore, I think. The heads were fine but the bolts, even though they are necked down to prevent seizure, were so pakced with rust in the bore that one was totally unremovable. I had to torch the head off the bolt, and even then I couldn't pull the hub. I finally had to torch one ear off the hub itself, and even then I couldn't get the stub of the bolt out of the knuckle. I hammered, drilled, and finally had to burn it out bit by bit. I finally was able to use a bfh and a punch to drive out the last inch and a half or so. Another one of those simple jobs that ends up taking half a day.

5-90 - What, did you have a stroke? Or a crash? I'm glad you're okay. I know recovery is a frustrating thing. I was involved in two separate crashes in my wild younger years, both with severe head trauma. Guess I've just been very, very lucky and blessed that I was able to recover twice (though my ex-wife might disagree). Ha!

Two weeks ago one of our D/FW local city drivers, a Veteran and a great guy, about 40 years old, had a stroke, caused by a ruptured aneurism in his head. He was comatose and paralyzed on the left side at first. But he woke up after a few days, and is already regaining some motility, so his prognosis went from them expecting him to die within days, to excellent potential for a full recovery, in two weeks. Amazing! We've all been praying hard. It remains to be seen whether he will ever drive again, but he is much better, and for that we are very thankful. His name is Val, so put him in your prayers.

Well, I got my nap out and some coffee in me, so it's time to get out there and get those brakes together. No rest for the wicked, eh?

Matthew, I know exactly whereof you speak. Sometimes it seems like I never will finish this thing, and I'm already a month behind the schedule I had in my head. Everything takes twice as long as I thought it would, especially with ordering the parts and then trying to get the right ones after they send the wrong ones one or more times. Oh, well, progress is progress.

kloker said:

Cool! Thanks, 5-90. That should be a sticky in the Tech How-To Section I know is gonna be on here one of these days. Great information. Just goes to show that even on my 56th birthday (Say Happy Birthday, Larry!) I can still learn something new. I really never thought about this. 'Course, back in my racing days, in the 60's and 70's, I'd never heard of anti-seize.

Anyways, I won! I got the thing out,and all by myself, too. Duh! It didn't occur to me that if you can't get the hub off, you can't get the knuckle off either, the shaft is in the way! So, after I wasted an hour busting all those ball joints loose, I ended up deciding to hacksaw the bolt head off. It only took 30 minutes, once I figured out how to do it.

Once again, all I have to do is outsmart the cast iron. Once I got the hub off I had plenty of bolt shaft left to get hold of with the pipe wrench, and it came right out. Jeez, I should have just done that in the first place.

I already had the new shields, and I wanted to check on the bearings and clean up the whole rusty mess anyway, so that's why I pulled the hubs. I always seem to make it harder on myself by going farther than I need to, and end up creating a bunch of extra work to get it done. But, if or when I need to go back in there, it'll be easy next time. Like, if the shields give me problems, it'll be easy to get them off.

So now all I need to do is clean it all up and get it back together, and I have all brand new front brakes.

Next up, rear disk conversion. I've decided to go with ZJ parts, so I just have to scrounge all that up. When it's done, I'll have all new brakes all around, including all the lines. No more rust problems there.

Then it'll be lift and suspension time. After all this, I know that'll be a blast!

Click to expand...

It sounds like you're gonna be wheeling this thing some, it's actually a good thing you got those old rutsy bolts replaced & anti-sieze on now. That'll make it much easier if you break an axleshaft or u-joint out on the trail!

jfiscus - yeah, my thoughts exactly. And, if I'm having this much fun with the brakes, I can only imagine how much fun the suspension and lift work will be. Lordy! I can hardly wait.

Crash. 08NOV2005, I got hit by a car while (we think - I have no direct memory...) picking up a load that someone else lost on the freeway, and was probably blowing around making a nuisance of itself. We've spent some time reconstructing the day (based on pattern of injury, vehicle that hit me, prior behaviour, and suchlike...) and it seems that I was picking up some loose rubbish bins, I was getting out of traffic, and my right knee gave out.

I was hit by a 2003 Taurus wagon doing about 60 at the time and thrown a good forty feet.

Now - here's the interesting part... I spend four days in hospital on morphine (I missed that!) while they were deciding whether or not to drill a hole in my head to let the pressure off from the intracranial bleed (they decided not to.) I had a pelvic fracture, three broken ribs, a broken nose, and a shattered face - but all the fractures were non-displaced. No surgery (not even blood!) and I just had to stay flat-arsed or in a wheelchair for two months.

The brain injury is still a problem - I lost six languages (but, fortunately, no technical knowledge...) and if I'm tired, hungry, or stressed, my left eye won't quite track and focus at the same speed as my right. And, I gained 25 pounds while I was flat-arsed. And, I've lost some upper body strength (which I've got to work on.)

I'm no particular stranger to recovery (blown knee, tore my erectors, had my right shoulder put back together, ...) but I've not had a brain injury before. I don't like it. So yes, it's damned annoying having to wade through all of this - and I've been informed that brain injuries can take 2-5 years to fully heal! Ugh...

kloker said:

5-90 - What, did you have a stroke? Or a crash? I'm glad you're okay. I know recovery is a frustrating thing. I was involved in two separate crashes in my wild younger years, both with severe head trauma. Guess I've just been very, very lucky and blessed that I was able to recover twice (though my ex-wife might disagree). Ha!

Two weeks ago one of our D/FW local city drivers, a Veteran and a great guy, about 40 years old, had a stroke, caused by a ruptured aneurism in his head. He was comatose and paralyzed on the left side at first. But he woke up after a few days, and is already regaining some motility, so his prognosis went from them expecting him to die within days, to excellent potential for a full recovery, in two weeks. Amazing! We've all been praying hard. It remains to be seen whether he will ever drive again, but he is much better, and for that we are very thankful. His name is Val, so put him in your prayers.

Well, I got my nap out and some coffee in me, so it's time to get out there and get those brakes together. No rest for the wicked, eh?

Matthew, I know exactly whereof you speak. Sometimes it seems like I never will finish this thing, and I'm already a month behind the schedule I had in my head. Everything takes twice as long as I thought it would, especially with ordering the parts and then trying to get the right ones after they send the wrong ones one or more times. Oh, well, progress is progress.

Click to expand...

5-90 - Ouch! Sounds like you are pretty lucky too. I can relate to the eye problems and the "data loss." In the accident on my 16th birthday, my optic nerves were shocked, and my eyes were all out of whack. The stereoscopic "aiming" that aligns the two eyes so that you get coordinated function was askew, and I saw one and a half of everything. Also, they stayed dilated for freaking ever, and focusing was seriously impaired. Luckily it gradually healed over about ten weeks, after which it came all the way back to normal. One thing I know you will know is that people who have not been where we've been don't know what a real headache is. Those headaches are what i remember most about the whole ordeal. They were way worse than the broken bones, and were the reason for 90% of the heavy drugs I had to have. I absolutely could not tolerate them without the drugs. They were also the reason I had to stay in restraints for so long, as I could not stay still on my own when they were happening, which was bad for the neck injury. My ability to think and then speak clearly came back over just a few weeks, but my memory "gap" never did. I am missing a few weeks. I have had glimpses of details, but it never came back. That's okay, some of it I wouldn't want anyway. On a humorous note, the buzz-word "fuzzy logic" is not one I find all that amusing.

Anyway, I'm glad you are getting better, however slowly, any progress is better than none. After I was able to be up and around, I spent a lot of time sitting outside in the sunshine, albeit maybe in a wheelchair. I found it was what I had missed the most, and to this day, it soothes me more than anything else can. I still love to be out in the sunshine, and I do it all I can.

Yeah, I'm also missing two weeks of memory (in addition to German, Italian, Spanish, Russian, Arabic, and Latin. I can remember that I used to speak them - but I probably recall maybe a dozen words in each...)

Oddly enough - no direct eye trauma. Fractured the roof of each orbit and broke both zygomatic arches tho. Fortunately, my EENT is an old flight surgeon (so I know how to handle him...) and orthopaedists tend to be fairly free with the pain meds (they KNOW that broken bones hurt!) so I stayed fairly well supplied for the first few months.

Problem was, I've got abnormally high resistance to most medication (comes from my mother's side of the family - we're all that way,) so it was no trouble taking Vicodin four at a time. Just to take the edge off of what I was feeling so I could think (I tell you, broken ribs thoroughly SUCK. Most other things you can keep still so they don't hurt...)

Anyhow, the vision trouble I'm having is related to the blunt force trauma to the visual cortex - the eyeball is just fine. There are just times where it "lags" - and when I've got to track things a little faster than I do when I'm sitting at my desk, I just wear an eyepatch (it's gradually getting better, and at least I haven't been downchecked for it. I've been checked by both an opthalmologist and an optimetrist, so the eyepatch while driving isn't a problem.)

"One and one half of everything" is about right - it's not quite double vision, and it's not quite blurring out - so you probably know exactly what I'm dealing with. When the objects are fairly static, my left eye catches up rather quickly and I don't have trouble. When they're moving, I can use one eye or the other, but not both (and, since my right eye is marginally faster than my left at present, I cover the left and use my right. Either eye can work fine on its own, tho, so I sometimes shift to patch so I don't get a "lazy eye.")

It's uphill work, but I'll get there...

kloker said:

5-90 - Ouch! Sounds like you are pretty lucky too. I can relate to the eye problems and the "data loss." In the accident on my 16th birthday, my optic nerves were shocked, and my eyes were all out of whack. The stereoscopic "aiming" that aligns the two eyes so that you get coordinated function was askew, and I saw one and a half of everything. Also, they stayed dilated for freaking ever, and focusing was seriously impaired. Luckily it gradually healed over about ten weeks, after which it came all the way back to normal. One thing I know you will know is that people who have not been where we've been don't know what a real headache is. Those headaches are what i remember most about the whole ordeal. They were way worse than the broken bones, and were the reason for 90% of the heavy drugs I had to have. I absolutely could not tolerate them without the drugs. They were also the reason I had to stay in restraints for so long, as I could not stay still on my own when they were happening, which was bad for the neck injury. My ability to think and then speak clearly came back over just a few weeks, but my memory "gap" never did. I am missing a few weeks. I have had glimpses of details, but it never came back. That's okay, some of it I wouldn't want anyway. On a humorous note, the buzz-word "fuzzy logic" is not one I find all that amusing.

Anyway, I'm glad you are getting better, however slowly, any progress is better than none. After I was able to be up and around, I spent a lot of time sitting outside in the sunshine, albeit maybe in a wheelchair. I found it was what I had missed the most, and to this day, it soothes me more than anything else can. I still love to be out in the sunshine, and I do it all I can.

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