Michael,
I started a reply to you a day or so ago, and got bogged down with other
stuff, and hope that the following is not repetitious or unhelpful (or just
plain too late!).
I saw a few replies about helicoiling and otherwise fixing up the threads
on the trailing arm casing, but I thought that wasn't the problem you were
addressing. It seemed that you had a case of studs + nylocs unscrewing
completely, rather than the Nyloc nuts alone, thus leaving you with 4 nuts
+ studs assemblies in your hand, with pretty good threads in the trailing arm!
If that is the case, the following might help (if not, ignore my ramble,
but it might help someone else eventually!).
It is not uncommon on smaller studs for the Nylocs to become attached to
the stud pretty firmly after a while. Nylocs are designed to grip, and
sometimes they grip rather more than the stud-to-casting thread. This
isn't a bid deal as long as you know: 1. how to remove the Nylocs, and 2.
how to fit the studs back into the casting. The secrets are thus ....
To remove a nut from a stud - whether Nyloc or just plain ordinary - is
pretty straightforward. The incantations follow:
1. Hum slowly the Lucas song "... and put a beer or 2 on ice"
2. Get a plain nut that fits the stud thread (remember some studs have
dissimilar threads from end to end - in that case get a plain nut for the
end that does not have a Nyloc nut fitted).
3. fit this plain nut (all by itself - not fitted to the stud) in to a
bench vise so that one of the 6 corners is upper-most. Carefully saw with
a hackwaw through the corner into the center of the nut. The bigger the
gap the better, so do not make this dainty. DO NOT GO OUT THE OTHER SIDE
OF THE NUT. If you do, you will have a 2-piece nut (would work, not
needed) and you will have ruined a large vise. To say nothing of the
energy wasted!
4. carefully spin (well, fit with a spanner would be more realistic) the
split nut onto the stud so it is completely threaded on to the stud.
5. hold the split nut (plus stud) vertically in said vise so the stud plus
split nut are gripped across the flats. The split on the nut should be in
the space between the vise jaws so it will tighten on the thread as you
tighten the vise. Tighten the vise so nothing moves, but not to the point
you crush the split nut. This should leave you with a split nut squashed
onto the stud in the vise, and a Nyloc nut attached to the top of the stud
well clear of the top of the vise.
6. get a 7/16 spanner and undo the Nyloc and throw in the bin.
7. release the vise and remove the split nut from the stud.
8. repeat 4 times
9. open the can of cold beer and take 1 sip and say, "thank you, Part 1."
Now you have the studs and nuts separated, you need to fit the studs back
into the trailing arm. Follow the following:
1. get 2 plain nuts of the correct size and thread form for the outer part
of the stud - not the bit that goes into the trailing arm (THEY MUST NOT BE
NYLOCS). DO NOT SAW THEM. Spin the first one on, and then the second.
Both must be fully threaded onto the stud. Spin them together with finger
force.
2. slip a ring spanner over the 2 nuts, and then find the elusive second
ring spanner of the same size. Fit one ring on one nut, and the second
ring on the second nut, and tighten them towards each other firmly. This
sounds more difficult than it is (you may need the spilt nut from above to
make it easier, but it isn't necessary). At the end of the process you
have produced a LOCK-NUT assembly. This device allows you to turn the stud
with ease since the nuts and the stud are LOCKED together. It ain't my
invention. Thank Joe Whitworth for this one (and maybe his friend
Archimedes).
3. Now fit the stud into the trailing arm and using a socket and torque
wrench. Torque the stud down to the correct torque. If my factory manual
wasn't in the upstairs loo (three floors away) I'd look it up for you ...
let me know if you need the info - and don't ask the other question.
4. Now the fun part. Get the above 2 wrenches and carefully fit them to
the 2 nuts, and move them apart without upsetting the torque loading (it
can be done, and this isn't NASA at the end of the day). Now spin off the
2 plain nuts.
5. To help avoid the problem next time round, you can install the studs
with Locktite Red. This chemical compound will lock the stud in place
pretty well, and stop stud removal when you undo the Nyloc. You can also
save some money on that front by asking you wife/girlfriend for a nail
color no long in fashion and coating the threads with nail varnish. For
non-heated applications, it has similar performance (well, in my opinion,
and after 25 years of using it!).
6. Buy NEW Nylocs (old ones are not guaranteed not to release with
vibration and so on), and refit everything as before.
7. Get that beer, take a deep draft and thank Joe Whitworth, Archimedes and
me! Cheers!
8. Sit back and enjoy another LBC moment
Tony Gordon
Midland, MI
>My rear suspension rebuild is going well with all the list help. But,
>when I went to release the 6 nuts to remove the right half-axle/hub
>assembly, 4 out of 6 studs unscrewed totally. It appears that the
>threads were good, but now I have 4 full studs with nuts which are at
>the point at which they were tightened down. I assume there may be no
>problem if I can screw them back in carefully with a torque wrench. Any
>comments as to returning the studs properly - to avoid stripping out the
>aluminum threads in the trailing arms, would be much appreciated.
>
>Thanks for your help, D. Michael
>
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