Looks like it was hit with a grinder when someone, at sometime was working on it and had trouble removing the screws. Carb will likely need cleaned or rebuilt.
I will double box and pad this engine as it weighs nearly 30 pounds. The item "1946 Schwinn Whizzer Motor Bike Engine Model H 4 Cycle Air Cooled Vintage WMH-20" is in sale since Sunday, October 18, 2020. This item is in the category "Collectibles\Transportation\Bicycles\Bicycle Parts". The seller is "tchvintageselections" and is located in York, Pennsylvania.This item can be shipped to United States, Canada, United Kingdom, Denmark, Romania, Slovakia, Bulgaria, Czech republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Australia, Greece, Portugal, Cyprus, Slovenia, Japan, China, Sweden, South Korea, Indonesia, Taiwan, South africa, Thailand, Belgium, France, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Bahamas, Mexico, New Zealand, Singapore, Switzerland, Norway, Saudi arabia, United arab emirates, Qatar, Kuwait, Croatia, Antigua and barbuda, Aruba, Belize, Dominica, Grenada, Saint kitts and nevis, Saint lucia, Montserrat, Turks and caicos islands, Barbados, Bangladesh, Bermuda, Brunei darussalam, Bolivia, Egypt, French guiana, Guernsey, Gibraltar, Guadeloupe, Iceland, Jersey, Jordan, Cambodia, Liechtenstein, Sri lanka, Luxembourg, Monaco, Macao, Martinique, Maldives, Nicaragua, Oman, Pakistan, Paraguay, Reunion, Uruguay, Russian federation.