Hi Georg
That was er 32 years ago, Peter, and I really can't remember what we had! I think it was a 5 hp. I know it started on petrol and then ran superbly on paraffin. At the moment we have a 1988 Tohatsu 3.5 two stroke on our tender and that still runs well, serviced regularly as Peter says. I hear that the innards of all such small engines have more or less identical innards.
I'll ask my daughter what she uses - she's an outboard on their Kingfisher 20 in the French Alps. I'll get back to you.