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Note that Posidriv is not the same thing as “anti-slip”. Phillips screwdrivers described as anti-slip are regular Phillips
screwdrivers with tiny ridges on the tip to supposedly keep the bit from slipping.
Meboe is quite right about all of the Phillips-looking screws being Pozidriv; the little screws on the taillight lenses, the
big screws holding the mirrors on, the small screws holding the ignition pickup in the distributor, everything is
Pozidriv. However, if your car has had any work done that may have involved replacing screws, chances are (in the
US, anyway) that the replacement screws are Phillips. So, you may need both types of screwdriver to work on the car.
You could closely inspect each screw before choosing a screwdriver, but that’s a pain and strains the eyes. Instead,
proceed as follows: Assume all screws are Pozidriv until you find a screw that the Pozidriv screwdriver won’t even fit
into, then pick up the Phillips.
LOCKING WIRE AND TOOLS: Several places on the XJ-S call for locking wire, safety wire, siezing wire, whatever
you call it -- notably on the braking system and IRS. You can buy suitable plain steel wire anywhere, even at Wal-
Mart. Of course, you want it to look nice, so you want stainless steel wire. Many places sell one size of SS wire, 19
gauge, which is actually about right for most purposes. Note that you need a soft alloy for this job; many types of SS
wire, such as fishing leader wire, are too hard for lockwiring.
If you want to get fancier, specialty stores sell stainless steel, inconel, or monel wire in various gauges along with
“lockwire pliers”. Lockwire pliers are a specialized tool with a latch that holds the jaws clamped down on the wire and
a spiral slider that spins the pliers with a simple pull. Lockwire pliers are popular with aircraft mechanics who may be
applying lockwire from sunup to sundown, but for XJ-S purposes they are not really justified; you can do the few
lockwiring jobs found on this car in a couple of minutes with regular pliers.
The theory of lockwire is simple enough, but aircraft mechanics and FAA inspectors will tell you that its use requires a
specific technique and careful application to ensure the intention is achieved: Safety. Applying lockwire requires a
bolt head with a hole drilled crossways through it; sometimes two holes are provided just to allow the choice of
whichever one lines up the best. Often it’s the fact that the bolt heads have such holes that tells you that lockwire might
be a good idea in this location. Insert the wire through the head of the bolt, wrap one end around one side of the bolt
head and underneath the other end, and twist them together in the direction that is likely to keep the wire around the
side of the bolt head instead of flipping off the top. On a right-hand-threaded bolt, the end wrapped around the head
should wrap to the right, and the two leads should be twisted to the right. Twist enough wire to reach a second bolt
head and insert one of the wires through that one, wrap the other wire around the head (this wrap will actually be to the
left, since you are going the other direction), and twist the ends together on the other side (a left twist this time). The
twisted section between the bolt heads doesn’t need to be in tension, but there shouldn’t be much slack in it. The
twisted section should come to a hole on the right side of each head (looking at each from the other), so the two bolt
heads and the twisted strand form a Z pattern. If done correctly, the wire between the bolt heads as well as the wraps
around the bolt heads themselves are arranged so that neither bolt can turn in the loosening direction without stretching
the wire. Finally, clip off the excess wire and bend the tip of the last twisted section back on itself to keep from
snagging yourself on it when working in the area.
If you happen to be lockwiring a single bolt, you will need to tie the other end of the lockwire down to something
nearby to effectively prevent the bolt from loosening. If you happen to be lockwiring three bolts, you can tie all three
together by simply continuing on past the second to the third. If you happen to be lockwiring bolts that are pretty far
apart, you may choose to tie each to something nearby rather than to each other, or to wrap the wire onto something in
between rather than leaving a long span unsupported; vibrations may cause a long section of wire to wiggle, eventually
breaking off.
If any of this is unclear, you can probably drop in on any aircraft maintenance shop and pick up a few pointers. It is
rather important that you get it right, obviously.
If you decide you’d like more safety than was originally provided for, you can drill lockwire holes in bolt heads that
don’t come with them. This is popular in racing, and some racing venues actually have specific requirements for things
that must either be lockwired or provided with tabwashers or self-locking nuts.