Join Date: Jun 2005
Location: Dobbs Ferry, NY
(I hope I'm remembering this correctly)
In the late 1970's, I had a '71 Spider with a Shankle Sure Start and the car had this same problem. I brought the car to the mechanic (he was a well-known senior mechanic from Alfa Romeo, Inc. in Englewood Cliffs, who had retired and started his own shop), who showed me that at full "lean" position, the Sure Start plunger did not extend as far as the plunger of a hot TA, thus the car always ran rich.
We fixed the problem by re-installing a good TA, and then re adjusting the fuel cut-off solenoid and other mechanical adjustments.