“How long did you say the engine sat idle?” What should be done to an engine to return it to service after it has sat idle for years? Answering that question requires the answer to several other questions: Was the engine preserved before it was put into storage? Was it stored in a climate controlled facility? No? Out in the weather? Were the exhaust stack(s) and carburetor air inlets plugged? Was the engine periodically run-up to operating temperature? Did it have preservative oil ran in the engine before entering storage?