Welcome! Here are the website rules, as well as some tips for using this forum.
Weil McLain boiler short cycle gas valve
GV 1013-200 controller.
Boiler cycles thru startup sequence, no flashing lights.
Igniter comes on, gas valve opens, burner lights, igniter turns off, burner remains lit for two to twenty+ seconds, all lights steady on. Then gas valve closes.
Cycle repeats immediately ( never locks out). Flame runs for variable length of time.
Sometimes after doing this a dozen times or so it will remain on and normal heating sequence works (cycling based on return water temp)
Replaced controller three years ago, Installed jumper to eliminate the always flashing #2 light.
Boiler is About 25 years old. New circulator and water temp switch Two years ago.
Could it be a gas quality/Orifice issue?