Date: Wed, 21 Mar 2001 01:43:58 -0500
Reply-To: David Beierl <dbeierl@ATTGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: David Beierl <dbeierl@ATTGLOBAL.NET>
Subject: Re: Heater motor replacement
In-Reply-To: <20010321053711.LMWE24361.tomts7-srv.bellnexxia.net@A3K1M0>
Content-Type: text/plain; charset="us-ascii"; format=flowed
I must beg to differ with both the honorable gentlemen: Those "shear bolts"
have absolutely nothing whatsoever to do with safety. They are there for
the purpose of making it difficult to drop the steering column, hence more
difficult to get to the ignition lock to disable it. In other words, they
are tamper-resistant bolts. The "shear" part refers to the head which
shears off when you tighten the bolt, thus supposedly making it impossible
to get the bolts out without drilling. Aside from that they are perfectly
ordinary M10 (?) bolts. They do not have any more influence on crash
behavior than do the perfectly ordinary bolts installed lower on the
column. The Vanagon steering wheel is designed to fold forward into the
dash, not down through the floor, and if you examine the locating brackets
inside the dash you'll see that they are slightly folded so as to make sure
that they collapse properly in a crash, just as the hoods of regular cars
have notches in their stiffening beams. These brackets are attached to the
infamous shear bolts, and they are (intentionally) much weaker than the
bolts. Anyone may verify this by inspection and by considering where the
forces in a crash are applied.
People who believe that the thief is going to pull the lock with a
slam-hammer instead of trying to drop the column and disassemble it will be
happy with ordinary bolts which cost a lot less than $8 apiece, which is
what the dealer gets for the unsheared shear bolts. Anyone who wants a
slight discount from the dealer price may make an offer to me for the pair
of new ones I bought just before I learned/figured out the above -- the
first clue was the service manager looking at the brand-new bolts in my
hand and telling me "they're for theft resistance..."
david
At 12:37 AM 3/21/2001, Alan Beck wrote:
>Are you absolutely certian you understand all the metalurgy behind
>that shear bolt? It may look OK, but is it? You did have to apply
>rotational torque to remove it, who says that does not affect the
>bolt somehow.
>
>
>On 20 Mar 01, at 11:09, KENWILFY@AOL.COM wrote:
>
> > come out very easy. The main thing is to NOT replace them with normal
> bolts
> > as this could cause serious problems in an accident (steering column not
> > collapsing and spearing the driver).
> >
> >
David Beierl - Providence, RI
http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage"
'85 GL "Poor Relation"
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