My boat (1990 34 + AKA 34/36) came with a Martec Folder in bad need of a re-build (1/2 inch of play at the blade tips) . It was not mounted and the boat had a fixed pitch 3 blades. I sent it for a rebuild and Martec recommended that we should change the specs from 16D X 12P to 16D X 14P so I went with it and ended-up with a like new refurbished hub and new blades.
After being in the yard since late Feb I finally splashed back in this past Tuesday (Yeah! More on that later) and tested it. It does take a bit of revs to get some action in reverse but I think it's not bad at all. My observation compared to the fixed 3 blades is that the acceleration from a dead stop is somewhat sluggish BOTH forwards and reverse, to tell you the truth I don't think either is better than the other, I think that there might be a perception that reverse is worse (Or much worse) because it's typically used as a brake and is needed right now. Once that is understood, with a modicum of care and planning I don't see how that will impede the boat's maneuverability in any significant way, at least for what I'm doing. As for Martec's advice on pitch, it appears spot-on. The max revs are right between 3400 and 3500 which is the same as what I had on the 3 bladed prop and as I was told, correct for my engine (3GM30F) . I don't know about the SOG yet as I'm not quite done with the new instruments install. The only fly in the ointment is more vibrations. It does not feel like the drivetrain is shaking apart but there is a noticeable increase in the vibration level at all RPM's. I called Martec and was told to start by looking for the usual suspects: Engine mounts, Cutlass bearing (Mine is like new), and engine / shaft alignment. The 3 bladed prop did vibrate at 2900 rpm and up so the Martec guy says the "More flywheel like" folder is amplifying the issue. We'll see. I have seen the thread on the guy whom had a folder vibration problem on his 34/36 where the blades were too close to the hull.. My vibration is not near as bad as what he described (At least I don't think so) and the Martec folder was a factory option on my boat so on this I assume that we should be OK on the blade distance to the hull. The engine mounts look fine but the alignment probably has not been done in over 10-15 years if ever so It's probably a good thing to check it out. Yet.. Another project to add to the 45 items list I have so far for 2014. :-( I'll report back on how she sails later. I'm hoping to be sailing on Sunday and Monday, -Francois 1990 34+ Take Five Lake Lanier, Georgia
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