I've heard of this before.
Fuel tank had to be cleaned.Replace or clean your filters remove
fuel line from tank and place in can of
fuel ,start bleeding at filter and work your way to
lines on cylinder head.There should be compression release at valve cover, use starter 5 seconds at a time cmpression released then close them,if it starts tank or pick up tube may have trash stopping them up some pick up tubes have screen on end.DO NOT USE STARTING FLUID,
GOOD LUCK HOPE THIS HELPS