Small Engines (Lawn Mowers, etc.): jiffy ice auger only runs on primer, reed valves, short money

Question
i have a jiffy ice auger,model av520. circa 2001.engine will only run after being primed cuts out after 20 secs.have disassembled carb, soaked,cleaned,+blown out passages.found no varnish or debris.replaced diaphragm,inlet needle+seat,replaced all gaskets.checked reed valves ok.idle+main mixture needles adj to tecumseh tech manual specs.checked all of the obvious?ignition ventcap compression.did not remove main nozzle (jet) welch plug.could it possibly be a main nozzle (jet) check ball problem?engine has approx.7hrs total run time.run a 24:1 in temps0-30.always fresh fuel.this clunker has never ran right since day one....i got it second hand in 2003 for short money.now i know why.its gotten worse each season. always drained tank line +ran gas out of carb for summer.any ideas would be greatly appreciated.thanks.

Answer
Hi Ronny,

Well, it sounds like you've pretty much covered the bases as far as checks and troubleshooting steps so... I will just go over the most common reason for the difficulties you are experiencing.

For a Fuel System Problem

1. Plugged tank Filter or Vent
2.  Fuel Pick-Up restricted

3.  Idle Port Restricted  
4.  Damaged adjustment needles
5.  Incorrect Float Height
6.  Main nozzle restricted
7.   Dirty Stuck needle - seat
8.  Fuel Inlet plugged

You could check the governor and see if it is functioning properly.

Other than these items I am not sure what else you could check.

Good luck,
Let me know.

Howard