The guidance I received is that the shaft needs to be a tight fit inside the coupler. The matched prop shaft and coupler set I got back from the prop company would not slide together by hand, needed light taps from a rubber mallet. The company said if there was much play and even a slight bit of misalignment causing vibration that overtime it would wear down any high point or possibly the set screw.
So it may be that the previously tightened and seizing wired set screw is not backing off, the end is wearing down until it appears to be loose. Michael Brown Windburn C&C 30-1 Date: Thu, 30 Jun 2016 21:17:42 +0000 (UTC) From: Daniel Sheer <dansh...@yahoo.com> To: Cnc-list CNC Boat Owners <cnc-list@cnc-list.com> Subject: Stus-List Transmission/prop woes Message-ID: <1554588852.4980586.1467321462816.javamail.ya...@mail.yahoo.com> Content-Type: text/plain; charset="utf-8" Just had my shaft slip out of the coupling as well. Zincs forward of the strut kept it from coming out of the boat. It was "lazy, hazy, crazy days of summer" getting the shaft back up so I could reattach it to the coupling. An hour and a half of "grunting and swearing and beer" before we were on our way again. Had holes in the shaft for the set screws. All on tight. Still came out. I put stop nuts on the set screws, and, since the key was moving as well, two hose clamps to hold the key in place. Also replaced the lock washers on the coupling bolts. We'll see. I'm checking it before each sail. Dan SheerPegathy - LF38Rock Creek off the Patapsco
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