Small Engines (Lawn Mowers, etc.): Stihl 028 WB chainsaw, diaphrams, gas additive

Question
I recently aquired this saw that had not been run in 8 years. Gas in tank was varnish. I dumped, and put pure gas additive similar to STP gas treatment(smells like kerosene).Took saw to a friend to work on it, and told him what was in the tank. He forgot to dump cleaner out, got saw running after cleaning out the carb. He called me and told me that the saw ran good, but was "smoking like a freight train". My question is- Could running this saw for a few minutes with no gas and oil, and only fuel additive cleaner have ruined my engine? He revved it up pretty good.We finally put a good mixture of gas/oil in it, but it would not run right. He says that it needs the two diaphrams, as they were a little "stiff", but other parts looked good. Thanks for your help.

Answer
 Hello Richard:

 The Mechanic was Lucky to Get it Running. Replace the Kit in the Carburetor. The Carburetor needs to be Soaked Overnight in Carburetor Cleaner and Then Blown Out with Compressed Air and a New Kit Installed. After Sitting 8 Years it was LUCK that it Ran with the Old Diaphragms. Hope this Helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks.

 Good Luck

 Respectfully

 John