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Re: DCO's and Suspension Woes (Hey, I'm a poet!)

Subject: Re: DCO's and Suspension Woes (Hey, I'm a poet!)
From: Scott Fisher <>
Date: Wed, 19 May 1999 10:26:24 -0700
Jason Dutt, inquiring about why his car rests at a higher position after
he lifts it, comments about Lawrie Alexander's well-let's-go-look
approach thus:

> Thanks for the info.  It's a distinct possibility.

I'm going to chime in here on the side of the voice of experimental
verification and say that *every* car I've ever worked under does
exactly this.  That includes Japanese, Swedish, German, Italian, and
U.S.-built cars as well as LBCs of several stripes.

Whenever I have to reach under a car -- for instance, to grab the drain
plug on the sump for an oil change, or to adjust an
externally-adjustable shock -- I find that my, er, manly chest (if we
can extend "chest" to mean the part of the torso that extends below the
rib cage, at least) gets blocked by the undercarriage of most
automobiles.  Fortunately, being a stout fellow in more ways than one, I
can always get just a tad of clearance by heaving upwards on the car's
bumper, chassis, or other fixed element.  Usually, this gives me about
an inch more room, just enough to reach under and snag the drain plug
with the wrench, and the car stays at the higher position for the
duration of my task.  I had exactly this experience about a month and a
half ago with my daily-driver Audi GT, which has MacPherson struts up
front, so it's nothing to do with Armstrong dampers or wonky bushings in
the ancient Morris suspension.  And I've done the same trick with cars
as new as three or four months old (the externally adjustable shock
trick, to be precise, at the rear of a then-brand-new Ford SVO
Mustang).  So it's not about wear in the bushings.

Why does this work?  My guess is it's simple: static friction is higher
than sliding friction, so when you lift the car up a *small* amount,
there's enough friction in the various bits that it will come to rest at
an equilibrium point where the forces and frictions even out.  

> However, (and I mean no
> offense in this), it seems every time someone has attributed various strange
> phenomenon on my car to "weird British engineering", they were sorely
> mistaken.  

Well, in this case, as I say, the phenomemon appears to be universal. 
And most "weird British engineering" makes perfect sense when viewed in
terms of the time and economy that the part in question was engineered. 
It's just that so many parts on our cars were engineered ten, twenty or
more years before the cars in question were built, so there are often a
range of mindsets in the same vehicle.  Found this most recently when I
helped a friend strip the trim off his '66 Bentley T Type prior to a
repaint; we removed Whitworth fasteners, Pozidriv screws, a few SAE nuts
and bolts, and at least four Allen-head screws.  As Berry said, "They
used exactly the right fastener for each application."  And considering
that only one stud snapped and one bolt was rusted in place beyond our
meager ability to remove it, out of the dozens if not hundreds of
fasteners we removed, that speaks well of Crewe's manufacturing process,
and of the engineers who specified the parts in the first place.  

Never forget that for the most part, our cars were designed to be taken
apart, worn bits renewed, new bits installed, and then reassembled. 
Wasn't it the late Roche Bentley who said "Drive your cars, for they
will surely outlive us all"?

On the other hand, I've never tried te lift-and-stick trick on a Morgan;
who knows whether it'd work on those famous sliding pillars?


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