Stefan
Do you have something against using some castor oil in your fuel or using a good after run oil at the end of the day? Klotz oil is an all synthetic oil and is not gererally rcommended by itself for ABN type engines. If an all synthetic oil fuel is used an after run oil is a must to coat the parts in oil to prevent rust. Synthetic oil does not leave a film on the parts and runs off leaving them exposed to moisture from the air. Some climates are worse than others as they have a lot of humidity.