Bolt Removal Problems

The head on the lower mounting bolt of my 91 Civic's rear left shock absorber
sheared off. Same for the bolt joining the control arm to the trailing arm. From
groups.googling, I see this is a common occurrence. So far I have broken two
screw extractors and one cobalt drill bit. I have got as much PB Blaster
(penetrating oil) in there as I could, short of soaking the whole assembly in a
bucket.

In the past, people have posted that they cut the bolt out.

Is there some kind of small, electric wheel cutter that will fit into this
somewhat tight space to do this?

What cutting points are recommended? Cut the nut, pry apart, then pull off? Then
maybe hammer what remains of the bolt through?

Also, what technique might be appropriate using a torch? I am thinking of buying
one of those $15 ones at True Value hardware IF someone thinks this with
something else is the better route to go.

I do have a used (7k miles old) strut (=spring over shock absorber) and control
arm to replace the old ones, so I can destroy them to my heart's delight, as
long as the car is drivable again within a few hours.

Suggestions welcome.

 

a regular grinder, with the edge going right into the bolt and nut? or
is it too close quarters?

yup. theres also a "nut breaker" google for that, but i still dunno what
kind of space you have to work with.

a torch is always handy too! supposedly, you want a MAPP torch, since
propane doesnt get hot enough?

in that case, an angle grinder will cut through anything. hell- try it
all! ive never had to buy a nut breaker, usually the angle grinder does
it all.

 

a regular grinder, with the edge going right into the bolt and nut? or
is it too close quarters?

yup. theres also a "nut breaker" google for that, but i still dunno what
kind of space you have to work with.

a torch is always handy too! supposedly, you want a MAPP torch, since
propane doesnt get hot enough?

in that case, an angle grinder will cut through anything. hell- try it
all! ive never had to buy a nut breaker, usually the angle grinder does
it all.

 

pick up a dremel, it'll get in some of the smallest corners and 35000 rpms
gets to cutting pretty quick =)

 

pick up a dremel, it'll get in some of the smallest corners and 35000 rpms
gets to cutting pretty quick =)

 

To clarify, do you mean the bolt that goes through bushing #20 in this
diagram http://tinyurl.com/3n3up ?

That sounds like bolt #25 at the trailing arm in the above diagram, correct?

Eric

 

To clarify, do you mean the bolt that goes through bushing #20 in this
diagram http://tinyurl.com/3n3up ?

That sounds like bolt #25 at the trailing arm in the above diagram, correct?

Eric

 

I can't seen any reason they can't just be pounded through, unless the nuts
are captive?

If the parts are being replaced, get the heat it.

 

I can't seen any reason they can't just be pounded through, unless the nuts
are captive?

If the parts are being replaced, get the heat it.

 

Yes. The bolt itself appears in the "rear shock absorber" drawing at
http://tinyurl.com/59d5k (item #20).

Correct.

I anticipate the same problem with *both* #25 bolts in this drawing. So far,
only the outboard bolt's head is sheared off.

If I want to replace the spring-over-shock absorber assembly, at least one of
those #25 bolts must come free, and in a way that doesn't damage the lower arm
(= trailing arm) or its bushing or the other #25 bolt's female fitting.

I'm not in any trouble per se (yet). The car is still drivable. This, as is
usually the case lately with my car work, is more about the journey (and maybe
overkill pre-emptive maintenance) than the destination.

 

Yes. The bolt itself appears in the "rear shock absorber" drawing at
http://tinyurl.com/59d5k (item #20).

Correct.

I anticipate the same problem with *both* #25 bolts in this drawing. So far,
only the outboard bolt's head is sheared off.

If I want to replace the spring-over-shock absorber assembly, at least one of
those #25 bolts must come free, and in a way that doesn't damage the lower arm
(= trailing arm) or its bushing or the other #25 bolt's female fitting.

I'm not in any trouble per se (yet). The car is still drivable. This, as is
usually the case lately with my car work, is more about the journey (and maybe
overkill pre-emptive maintenance) than the destination.

 

Yes, the nuts are captive (= welded in place).

A guy named "Boomer" here posted a few years ago that he just snapped off the
nut welded to the strut's fork bottom and then, as you suggested, pounded the
bolt through. But I've still found that getting the strut off requires also
removing at least one of the #25 bolts. This is necessary so the control arm can
swing down and fully disengage the strut fork.

I'm working on my options now, including one of these dremel tools (thanks MC
Tee) and maybe an angle cutter (thanks Mike). Space is a concern but I'm not
rejecting either of these possibilities. I'm also considering an air hammer on
the end of the bolt, applying torque via hard tapping, if I can squeeze the
hammer in there without risking life and limb.

 

Yes, the nuts are captive (= welded in place).

A guy named "Boomer" here posted a few years ago that he just snapped off the
nut welded to the strut's fork bottom and then, as you suggested, pounded the
bolt through. But I've still found that getting the strut off requires also
removing at least one of the #25 bolts. This is necessary so the control arm can
swing down and fully disengage the strut fork.

I'm working on my options now, including one of these dremel tools (thanks MC
Tee) and maybe an angle cutter (thanks Mike). Space is a concern but I'm not
rejecting either of these possibilities. I'm also considering an air hammer on
the end of the bolt, applying torque via hard tapping, if I can squeeze the
hammer in there without risking life and limb.

 

you can get the shock out without dropping that bolt, but dropping sure
makes life easier. the "without" method involves a heavy assistant
forcing the suspension as low as it will go - the torsion in the
bushings usually stops it going too far.

removing the nut on the forward facing part of the shock is not that
hard - it's just friction welded in there. a big wrench & a "torque
amplifier" soon has that thing turning. then you're in the business of
being able to pound the bolt through, if it's not already turning - it
usually just gets frozen inside the nut. for reassembly, just use the
appropriate metric nylock nut from your local hardware store.

if #25 bolt shears, you're going to have to carefully drill out i'm
afraid. modest heat helps, localized on the nut as much as possible,
[maybe by cutting a hole for the nut in some plumbers heat shield?] but
don't overheat because the trailing arm is subject to quite a lot of
flex and it could mess up the steel & start fatigue.

you can also drop the nut from the inboard side of the lower control arm
to get the clearance you need to get the shock out, but don't forget to
jack the trailing arm into position first.

 

you can get the shock out without dropping that bolt, but dropping sure
makes life easier. the "without" method involves a heavy assistant
forcing the suspension as low as it will go - the torsion in the
bushings usually stops it going too far.

removing the nut on the forward facing part of the shock is not that
hard - it's just friction welded in there. a big wrench & a "torque
amplifier" soon has that thing turning. then you're in the business of
being able to pound the bolt through, if it's not already turning - it
usually just gets frozen inside the nut. for reassembly, just use the
appropriate metric nylock nut from your local hardware store.

if #25 bolt shears, you're going to have to carefully drill out i'm
afraid. modest heat helps, localized on the nut as much as possible,
[maybe by cutting a hole for the nut in some plumbers heat shield?] but
don't overheat because the trailing arm is subject to quite a lot of
flex and it could mess up the steel & start fatigue.

you can also drop the nut from the inboard side of the lower control arm
to get the clearance you need to get the shock out, but don't forget to
jack the trailing arm into position first.

 

I may be mistaken, but it sounds to me like you may have been bitten by the
same problem that attacks the front suspension lower mounting bolt. That
is, it seems that Honda did not use any antiseize compound on these bolts
and they tend to rust up in the bushing. You may have success by twisting
off the captive nut on the back side of the strut yoke as others have
suggested. However, if the bolt is truly seized up in the bushing, then it
may require you to get a new bushing pressed into the control arm. It seems
unlikely that the small captive nut could provide enough clamping force on
the bolt to allow the head to be twisted off. It seems more likely that the
bolt shank is frozen up in the bushing. However, you may get lucky pounding
it out.

The trailing arm bolt is likely to more of a hassle. Here again, it may be
the case that the bolt is rusted into the metal sleeve of the bushing. You
could try drilling the end of the bolt where the head broke off so that you
can then insert a spiral screw extractor into it (always use a center punch
when drilling a bolt to get your drill started correctly). You'll likely
need a right angle drill due to the close quarters. If you can get a screw
extractor into it, then you might have luck by applying some gentle heat to
the captive nut on the far side. The other posters are correct in that a
mapp gas torch will be better than a propane torch as they burn hotter.
Heat the nut up until it just begins to turn red and then try loosening the
bolt (be careful of any fuel lines or brake lines in the neighborhood).
However, if the bolt shank is truly rusted up in the bushing, then this
process may not get you anywhere. If that's the case, then you may be able
to get a rotary cut off tool between the bushing and the trailing arm to cut
the bolt at both ends of the bushing. If you follow this procedure, you'll
need to get a new bushing pressed into the control arm so don't worry about
cutting it and keep your cut off tool away from the trailing arm. Note that
you'll still need to drill out the remaining bolt in the trailing arm or
find some way of removing the captive nut and replacing it with something
else. Good luck.

Another possibility is that you may have success by whacking the bolts with
an air hammer once you get the captive nuts removed. Unfortunately, this
might mushroom the end of the bolt and make drilling it much more difficult
if you wish to try that avenue later.

By the way, be sure to put some antiseize compound on any of the bolts that
you reinstall back into the suspension. I happen to be biased towards the
copper based antiseize but the other type (zinc based I think) should work
as well. Note that with the bushings, the antiseize should go on the bolt
shank as well as on the threads.

Eric

 

I may be mistaken, but it sounds to me like you may have been bitten by the
same problem that attacks the front suspension lower mounting bolt. That
is, it seems that Honda did not use any antiseize compound on these bolts
and they tend to rust up in the bushing. You may have success by twisting
off the captive nut on the back side of the strut yoke as others have
suggested. However, if the bolt is truly seized up in the bushing, then it
may require you to get a new bushing pressed into the control arm. It seems
unlikely that the small captive nut could provide enough clamping force on
the bolt to allow the head to be twisted off. It seems more likely that the
bolt shank is frozen up in the bushing. However, you may get lucky pounding
it out.

The trailing arm bolt is likely to more of a hassle. Here again, it may be
the case that the bolt is rusted into the metal sleeve of the bushing. You
could try drilling the end of the bolt where the head broke off so that you
can then insert a spiral screw extractor into it (always use a center punch
when drilling a bolt to get your drill started correctly). You'll likely
need a right angle drill due to the close quarters. If you can get a screw
extractor into it, then you might have luck by applying some gentle heat to
the captive nut on the far side. The other posters are correct in that a
mapp gas torch will be better than a propane torch as they burn hotter.
Heat the nut up until it just begins to turn red and then try loosening the
bolt (be careful of any fuel lines or brake lines in the neighborhood).
However, if the bolt shank is truly rusted up in the bushing, then this
process may not get you anywhere. If that's the case, then you may be able
to get a rotary cut off tool between the bushing and the trailing arm to cut
the bolt at both ends of the bushing. If you follow this procedure, you'll
need to get a new bushing pressed into the control arm so don't worry about
cutting it and keep your cut off tool away from the trailing arm. Note that
you'll still need to drill out the remaining bolt in the trailing arm or
find some way of removing the captive nut and replacing it with something
else. Good luck.

Another possibility is that you may have success by whacking the bolts with
an air hammer once you get the captive nuts removed. Unfortunately, this
might mushroom the end of the bolt and make drilling it much more difficult
if you wish to try that avenue later.

By the way, be sure to put some antiseize compound on any of the bolts that
you reinstall back into the suspension. I happen to be biased towards the
copper based antiseize but the other type (zinc based I think) should work
as well. Note that with the bushings, the antiseize should go on the bolt
shank as well as on the threads.

Eric

 

Based on my efforts today, you are correct.

Today I was stuck workingmostly on the rear outboard lower control arm bolt. I
ground it down with a hand drill grinding block. I then successfully drilled the
distance of its nut (or threaded female end; there's really no nut there that I
can see), starting with a cobalt 1/6" bit, then 1/8" bit, then another size up,
per the screw extractor table. I used Sears' cutting oil.

I tried some screw extractors with the cutting oil for a few hours but did not
want to break any and so finally gave up on it to ponder this overnight.

I then gave the inboard #25 bolt a try. I'd sprayed it a couple times with PB
Blaster since this morning. Hurrah! It came out pretty easily for a 13-year-old,
never been changed before, seen northern U.S. winters bolt.

I thought, "Great. I should be able to get the middle control arm bolt off and
at least change out the strut assembly today."

Wrong. What you described above is dead-on correct. I snapped off the
(middle)welded nut with a 1/2-inch drive 19 mm socket and a five-foot breaker
bar. It wasn't as dramatic as the crankshaft bolt but it came close. I then
tried pounding the bolt through the bushing, which didn't work. I then tried
double-nutting the forward, threaded end. I quickly found the whole bushing was
trying to turn as I turned the bolt!

As you suggested, the bushing is frozen to the splines of the bolt big time. I'd
likely end up destroying the bushing if I force the bolt out.

Yes. Luck. It was at a mininum today.

Yes, this is where I'm at.

Given what I'm seeing with the middle bolt, I think the screw extractors will
just keep breaking.

I think I'm going to put everything back together tomorrow, antiseizing the
inboard bolt like mad, of course, and give this a week to ponder.

It seems to me I am going to have to cut the bushings of the outboard bolt, then
extract, piece-by-piece, the remaining bolt, along the lines of what you
suggest. Probably have to tap the female threaded fitting on it. Tapping looks
very do-able right now, due to my fine drilling job. I think.

Do I read like the guys who put this car together?!

;-)

Yes, indeedy. (I draw from my ship experience here.)

Seriously, thank you for your help. It seems to me the key to this endeavor is
realizing it's the bushing, not the nut, freezing to the bolt. For it's whole
length.

 

Based on my efforts today, you are correct.

Today I was stuck workingmostly on the rear outboard lower control arm bolt. I
ground it down with a hand drill grinding block. I then successfully drilled the
distance of its nut (or threaded female end; there's really no nut there that I
can see), starting with a cobalt 1/6" bit, then 1/8" bit, then another size up,
per the screw extractor table. I used Sears' cutting oil.

I tried some screw extractors with the cutting oil for a few hours but did not
want to break any and so finally gave up on it to ponder this overnight.

I then gave the inboard #25 bolt a try. I'd sprayed it a couple times with PB
Blaster since this morning. Hurrah! It came out pretty easily for a 13-year-old,
never been changed before, seen northern U.S. winters bolt.

I thought, "Great. I should be able to get the middle control arm bolt off and
at least change out the strut assembly today."

Wrong. What you described above is dead-on correct. I snapped off the
(middle)welded nut with a 1/2-inch drive 19 mm socket and a five-foot breaker
bar. It wasn't as dramatic as the crankshaft bolt but it came close. I then
tried pounding the bolt through the bushing, which didn't work. I then tried
double-nutting the forward, threaded end. I quickly found the whole bushing was
trying to turn as I turned the bolt!

As you suggested, the bushing is frozen to the splines of the bolt big time. I'd
likely end up destroying the bushing if I force the bolt out.

Yes. Luck. It was at a mininum today.

Yes, this is where I'm at.

Given what I'm seeing with the middle bolt, I think the screw extractors will
just keep breaking.

I think I'm going to put everything back together tomorrow, antiseizing the
inboard bolt like mad, of course, and give this a week to ponder.

It seems to me I am going to have to cut the bushings of the outboard bolt, then
extract, piece-by-piece, the remaining bolt, along the lines of what you
suggest. Probably have to tap the female threaded fitting on it. Tapping looks
very do-able right now, due to my fine drilling job. I think.

Do I read like the guys who put this car together?!

;-)

Yes, indeedy. (I draw from my ship experience here.)

Seriously, thank you for your help. It seems to me the key to this endeavor is
realizing it's the bushing, not the nut, freezing to the bolt. For it's whole
length.

 

Update:
Unfastening the bolt connecting the rear lower control arm and trailing arm was
as ugly as others in the archives reported. I never actually got it free from
the bushing or its nut.

I never tried a torch, but that would be my next suggestion.

I eventually drilled and cut (by hand) the outside-most control arm
bushing/bolt. Then I ground down the female bolt receptacle (it's not actually a
nut, unfortunately, or I would have snapped it off, the way I did with the strut
fork bolt) welded to the trailing arm. I used a cheap-o electric hand drill and
grinding stone attachment. Grinding it down was no fun but at least I could see
some kind of steady progress. Cobalt drill bits are essential but still very,
very slow, even with the best cutting oil.

I installed the "new" (= 8k miles used) control arm last night, attaching it
with a separate nut at the trailing arm, as I think Eric and/or others
suggested. The new strut and control arm did not fix the tilt, but I wasn't
expecting it too.

The ride seems a bit smoother, but I may have talked myself into this.

I took apart the old strut in my suspension course today, borrowing the school's
spring compressor. The shock absorber seemed in excellent shape at 157k miles
old. The spring is a tougher call.

I reckon I spent around $35 just on cutting tools for this job. About half the
tools are broken or now severely worn. I'm worn, too!

I am contemplating doing the other side but not for another week or so.
Meanwhile, the other side's bolts get sprayed with PB Blaster regularly. Not
that I have much hope this will help.

Moral of the story: The classic, "If it ain't broke, don't fix it"?

I dunno. I learned a lot: -)