Installing an if the original is faulty.

Early models lacked the anti-vibration technology found in modern tools. 2. Fuel and Lubrication

Ensure the gap is set to the original manufacturer's spec (usually around 0.5mm to 0.7mm).

Are you currently facing a (e.g., won't start, leaking fuel)?

Modern "dry" fuels can damage vintage valves; consider using a lead substitute additive. 3. Starting Instructions (Inbetriebnahme)

Most gasoline engines from the early 50s required a specific oil-to-gas ratio. Often required a 25:1 or 33:1 mix.