- Jul 27, 2011
On Christmas Day 2013 backing our Bavaria 38E out of its slip I punched it in reverse, then lost backward (and forward) thrust quickly thereafter. Nearly side-wise now in the fairway, we blew up against the rip-rap within a few minutes and had to be pulled off by a rescue boat and ushered back into the slip. Diving on the Yanmar SD31 saildrive, our 16" x 13" LH 2B (fixed) aluminum propeller was gone; the 8 mm SS retaining bolt sheared at the end of the spline shaft. The prop evidently hit the hull starboard of the center line abaft the saildrive leg whence it came. The bolt was replaced (new) in 2006. A week prior I had had the boat out of the water for a bottom paint job and had taken off the prop for cleaning, and put it back on using that same bolt. Could the torque applied to the bolt when taking off the propeller have weakened it to the point of failing on strong reverse thrust after it was reinstalled? Or, might there be another "unseen" problem at work here?