Thanx for the info Gentlemen, I checked the serial number and it's 321185 , according to steampunk's link , gas engine magazine that number falls in the year 1931. The elbow for smoke stack is an add on , originally it had a little muffler there . My uncle added the elbow and made the smoke stack out of an old drive shaft. He thought it looked neater with stack, I tend to agree. Thanx for the help.