'74 GTV starting problem

[Loosej@xxxxxxx]

Alfisti,
  I have a '74 GTV with 2 40MM Webers.  It has a Marilliplex ignition system.
The new engine has about 500 miles on it.  When cold, it starts right up.
After being run a while, ie. it is warmed up, if I stop to fill it with gas,
it will start back up.  However, if after warming up, I stop it for say 20
minutes, it won't start back up.  It turns over, but does not even seem to try
to fire up.    I have to wait about 20 more minutes, then it starts back up
fine.  When running, it runs fine.  It is approximately 90 degrees here in
Houston now.
  My starting procedure has been to pump the gas pedal 3 times about an inch
or so  in before I try to start it.  Could it be my procedure?  Maybe after it
is warm, i shouldn't pump it, am I flooding it?  If it is flooded, is putting
the accelerator to the floor while cranking it  the way to un-flood it?   This
is my first car with carbs in a long while, so  any thoughts would be
appreciated.
  This has  happened 4 times in the last 2 days, but it has happened every
time I wait for 20 minutes before i try to restart it.
thanks for any help,
Joel Lewis
Houston
'89 Milano
'74 GTV

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