Tecumseh 6.0 HP Vector VLV60

Ariens Mower with the subject Tecumseh 6.0 Vector engine had been placed in storage in 2011 following inability to start and diagnosis of carburetor rebuild/replace required.  Mower is over 20 years old, but had performed so well for years, that I hung onto it (3 relocations) until I had time to get it running again. 
 
Mower was removed from storage most recently and replacement carburetor installed.   Mower started on 2nd pull and ran well until there was evidence that it was starting to overheat. It appeared that all the oil had either been consumed in consumption or had leaked out.   There was no evidence (deck, etc.) of oil leakage....Some white smoking occurred when the mower was first started.  I was not alarmed because of the length of time it had been in storage.   Changed the Oil the following morning (27 oz of Quality SAE 30 W oil).  Mower started and ran strongly until there was evidence of overheating again.   Stopped the mower and checked the oil...it appeared that all 27 ounces of oil in the sumb had either been burned in combustion or had leaked out again.   
 
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