Folding Propeller

[johar]

After sailing the other day on my Tartan 34-2 I came into my Marina under power fighting a stiff current. But after I came through the breakwater I had to come to almost a complete stop to wait for another boat. When I throttled up again, the boat wouldn''t move. I was up to about 3300 rpm on a 27hp Yanmar before it started inching forward. When I got the boat between the docks to head for my slip it seemed to operate normally again. I think the problem was either an underestimation of the current in the Marina (seems like a lot of current though), or maybe my folding prop was doing something strange. Does anybody have any thoughts on this, or experienced something similar with a folding prop? Any input would be greatly appreciated.

[paulk]

We noticed last year that our speed under power seemed to drop as the season progressed. We guessed that marine growth was hampering the opening of the blades, and sent an agile crew in a face mask down to clean it off with a putty knife. This year we painted it with antifouling (a multi-coat special primer operation, since standard anti-fouling will turn your bronze prop to swiss cheese if it''s just slapped on) and we''ve been more diligent about keeping it clean. We also had the prop re-tuned by the manufacturer. Lots of things could have caused your sudden problem. The strong current may have closed the blades when you slowed down and they could have gotten stuck closed, caught on a barnacle or other growth. We found that when the blades didn''t open properly, shifting into reverse and then quickly back into forward usually did the trick.

[johar]

Thanks for your input. I guess I''ll just try to clean any junk off of it and monitor it carefully for the rest of the season (only 6 weeks or so left in New York). And in the off-season I''ll have the propeller reconditioned as you did. Thanks so much for your reply.

[harvh]

Been there done that. After some frustrating and really scarey situations in Marinas, I finally sent the damn thing to Davie Jones locker and went to a feathering prop.

Two things I experienced. One of the blades would hang up while the other would deploy . When this happened I could not stop the boat. It also produced a vibration that freaked me out pretty good. The second situation happened when I would get partial deployment of both blades. The simptoms were a loss of power.

It could be you need to have your prop overhauled. If you really want to stop fast, go to a diffent prop.

[lastfreedom]

I also have a folding prop and seem to experience sporadic vibrations at higher rpms. I also have a saildrive and was wondering whether something could be amiss there too.