At 04:15 PM 10/14/2001 -0700, you wrote:
>Since my name has been thrown out a couple of times in relation to the
>fulcrum pin situation,....
>The normal OEM fulcrum pins typically fail at the reduction in diameter
>from 7/8" to 5/8" at the rear bushing. They fail at this location because
>of the combination of the cantilever design, poor Ackerman geometry and the
>stress risers that the change in pin diameter cause...
>
>Tom Hall
>
Tom,
Have you considered adding some sort of bracket to the front and
rear of the pins? Consider a steel bar roughly 14" X 1 1/2"X 3/4" welded to
the cross member parallel to the lower fulcrum pin with a couple of 1/2" holes
tapped into the ends of the bar.
Consider a nut welded to a plate that both screws on to the fulcrum pin and
can be
bolted to the end of the steel bar. This would solve the "cantilever" problem.
Shims might be required to get the desired compression on the A arm bushings
while
lining up the bolt holes on the cross bar.
The sway bar would have to be temporally removed to "screw on the
nut/bracket,
but if one is working on the lower A fram, the sway bar must be removed anyway.
Special fulcrum pins with longer threaded portions would allow the
regular nut to be installed while the extra plates (without welded nuts) could
then be secured with additional nuts.
This scheme would also help in case the bolts holding the fulcrum
pin decided to break.
Another alternative is to dispose of the lower fulcrum pin and
add 4 tabs to a cross bar welded to the cross member. Slip the lower A arm
with bushings into a pair of tabs and secure with a a pair of 5/8" grade 5 or 8
bolts, washers and nuts. The old fulcrum pin or a wooden moke-up bolted to the
cross member could be used as a jig to allow the tabs to be welded on in the
proper location. Of course; you would have to cut the old fulcrum pin
(or wooden moke-up) to remove it from the new tabs.
There are several ways to skin a big cat (Tiger).
James Barrett Tiger II 351C and others
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