In my continuing quest to reduce (no, I didn't say eliminate) the Morgan
Front End Shudder AKA St Malvern's Dance, I found myself under the front
wings, adjusting the damper blades one more time.
This time I decided to totally remove the blocks and shims on the frame,
with the thought of cleaning and lubricating the blade sliding surfaces
(hadn't done that yet). Much to my surprise, I found that the blades could
rotate independent of the kingpin-hub assembly.
Is this normal?
My understanding of the damper blade system was that the damper plate
should be fixed relative to the hub somehow, so that the shims could
prevent rotation and resonance of the hub. Here I have both sides that will
rotate over several degrees (translates to more than 1/2 inch of movement
at the frame shims on one side, and 1/4" on the other). This is with the
weight of the car sitting on the wheels.
Digging deeper, I look at the Morgan Shop Manual and the Morgan Spares
parts diagram
<http://www.morgan-spares.com/media/1_parts_book_graphics/combined/front_suspension.gif>http://www.morgan-spares.com/media/1_parts_book_graphics/combined/front_suspension.gif
, and it seems that there is only a _hole_ for the kingpin in the damper
mounting plate. (Part # 21)
Have I found the cause of the "dance" on my car? Should I try to eliminate
this movement? If so, how?
Atwell Haines
'57 4/4 "Yellow Peril II" (Drum brakes BTW)
Succasunna, NJ USA
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