(ET) Support arm came apart

[wilbett earthlink net]

When I backed up recently with my E12, the deck caught on something and 
pulled
the left support arm apart. The half inch rod and with the spring came out 
of the
plunger part of the arm. I haven't taken it apart yet  and don't have any
mechanical drawings in my copy of the manual. How is the rod supposed to be
stopped from pulling clear out like that? Is there something like a fat 
washer
with a drive pin on the rod end inside the plunger? The aft end of the 
plunger is
welded closed.
Bill A.