Just a reminder to those of us who have the Hurth 50. It is probably not the most robust design, I have had one apart and can see that how it works. Key thing to remember is to not sail when left if forward gear. Eventually, the force can over take the pressure plats and grind them so they will not hold. Go to neutral or reverse. I have been told that some prefer reverse because the lubrication is inadequate for the main bearings when the big gears are not sloshing the oil and that could be argued, but I cannot confirm. A service bulletin says put it in neutral or reverse and take your chances if you have a feathering or folding prop. FWIW.