All engine gaskets should always be replaced during an overhaul.
The easiest way to do this is to lubricate the gaskets with a little grease to make them stick to the housing and prevent them from being bent or damaged during installation. Sealing compound is only necessary if the housing is defective (scores in the sealing surface or similar).
If a healthy motor housing drips nevertheless, it is usually strained or crooked engine casing. A strained casing is caused by unevenly tightened housing screws. Ideally the housing halves should be tightened evenly (crosswise!) with a torque wrench. The maximum value here is 6-8NM according to Piaggio - specification.
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Brand new and unused