GRAVELY PROMASTER 200 RUNS ONLY ON CHOKE

I HAVE THIS GRAVELY ZERO TURN, I BELIEVE ITS A 1995, HAS A KOHLER CV20, 20 HP V TWIN MOTOR, WOULD ONLY RUN ON FULL CHOKE, CLEANED CARB,AND IT RAN GREAT FOR 5 HOURS,THEN STALLED AND AGAIN WILL ONLY RAN ON CKOKE, THIS TIME I REMOVERED THE GAS TANK AND FLUSHED IT OUT, IT REALLY WASNT BAD, I THEN REPLACED ALL FUEL LINES AND FUEL FILTER ,TRYED A FUEL PUMP OFF ONE OF MY RUNING MOWERS,AND AGAIN CLEANED CARB PROFESSIONAL,AND STILL RUNS ON ONLY CHOKE, I DONT BELIEVE ITS FUEL NOW. ANY HELP WOULD BE GREAT THANKS JIM. PS I ALSO CHECKED COMPRESSION 145 AND 150.

GRAVELY PROMASTER 200 RUNS ONLY ON CHOKE