A little History of the Westbend 820 Engine. The engines that have the West Bend tags are the earliest. First production was in late 1961 and sold as 1962 models; they will also have West Bend on the stuffers. 82006 models were made for chain saws according to West Bend documents. The earliest engines had steel cylinder head shrouds; they were changed to aluminum early on. You can try a magnet on the ones you have to see if they are steel or aluminum. The early pull starters are cast aluminum and are smooth on the outside; they also have a steel roll pin that the rope ties to in the rubber pull handle that you can see. The Chrysler Power Bee engines also have cast aluminum starters but the tooling was changed to add a raised area on the outside surface of the housing. The rope can not be seen in the handle because there is a metal plate that covers it. The West Bend kart engines were painted a champaign brown color and the Chrysler engines did not have paint. I don't know about chain saw engine color. To be correct for your early kart you should use the West Bend engines but once the paint is gone most will not know the difference. The crankshaft output shaft is stepped on kart engines and the engines that have left hand threads rotate clockwise when looking at the end of the shaft. The engines with right hand threads rotate counter clockwise. 820's weren't available until late 1961 early 1962.