How are the bearings on the Axle Drive ? Does the blower (Wheels) move freely when shutoff and gear selector in 6th ?
If all appears ok perhaps you have a bad seal (engine skipping) at idle , not enough base compression (sucking air) via the Crankshaft seal under load. Just a thought ..Ty !

Does it seem to be an engine runability issue to you? If the running is consistently poor then the likelyhood the carb still has issues is most likely. It isn't unheard of to have a kill wire/ switch that has come detached and grounds out the coil as the machine moves. model #s or at least the make /HP of the engine would give us better idea of what's happening.

Good point Tom , Seymour does the engine stall out with throttle on full without engaging the drive lever ? I would think that the vibration would be sufficient then to establish if Tom's advice on the Kill switch is an issue , if the wiring to the coil is intact . I assume the switch is the plastic key (pull out) Type that Tom is referring too ?

Thanks for advice. I'll look into both possibilities that were mentioned. The Blower is a Craftsman #536.918302 and is a 24" - 7HP. There is a key for on/off but it doesn't seem to work. I kill the engine by throttling down to the kill on the speed control. Is it possible that the key is supposed to work and that the issue is in that wiring? The engine does not stall out until I start moving. It has just a slight skip but has had that skip since I inherited it 6 years ago.

Actually Seymour the Kill Switch is just that a wire runs from the coil terminal and is isolated from metal contact via the Plastic key. when you pull out the key s set of contacts close grounding out the coil , shutting off the engine. Check to see if a wire from the coil exists , if so remove it if you using the throttle for shut off. The cut out during load ( drive usage) is a puzzle other than what I 1st indicated....sorry ..Ty !

P.S. Perhaps someone else has a better solution as per carburation...etc .

Look underneath the the heat box that goes around the carb. Under there is where the the kill wire is supposed to slip into the connector body. These slide out once in a while a just dangle there. That could also explain why the switch is inop. If it isn't off there, follow the wire into the shroud.