Life of Folding Propellers

Krusty

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What experience do people have of the life of a Gori 2-blade folding prop? Mine has given everything Gori promised performance-wise, but after 6000 hours it is utterly worn out. Is this a normal life? It is shaft-mounted with P-bracket and there is NO corrosion, but the sides of the blades and the faces in the hub slot, and the blade hinge-pin holes, (but not the gears) are now so worn the blades wobble about alarmingly. Any contributions?
 
Bloody hell, 6000 hours! At 5 hours a day that's 1200 days or about 10 years hard cruising. I'd be sending them a email saying what a good product they had.
 
I have a Volvo 3 blade folding prop which is now pushing 800 hours and it's blades are getting decidedly rattly. The wear seems to be on the hinge pin holes.

I was wondering if it is possible to get these machined out, bushed, or larger pins put in. Anyone know if this is possible?

Thanks
 
Ouch. My flex-o-folds have done 1400 hrs and move more freely than when new but with no sloppiness.

By the time they have clocked up 6000 hours I'll have covered the equivalent of 3 circumnavigations so I wouldn't be too upset at replacing them.
 
We've had very short life spans on two gori 2 blade folders fitted to a Yanmar saildrive. I would say we got 500 hours out of each before the teeth wore/corroded to the point of the blades jamming. The propeller is electrically isolated from the hub and has no anodes. Initially I thought it might be electrolysis but now I'm not so sure. I did a bit of research and found that they are made from Nickel Alumnium Bronze. This material although in many ways ideal will work harden with impact ie where the gearing is and where they fit into the slot of the collar. Where the metal is hardened in this way localised electrolytic corrossion can occur. I don't know what the answer is other than a different metal.
 
Snap. On our 1st boat we had a 2 bladed folding Volvo and it was replaced roughly every 600 hrs. On a charter boat that was 3 times. Finally gave up on the Volvo and bought a Variprop that was OK.

I believe the Volvo folding prop I had on the 2030 is manufactured by Redchi(spelling?) in Italy and it has a softer magnesium alloy for the splines. These progressively wear and I believe the prop starts running eccentric with the play which increases the wear.

I am not sure whether the short life is only the 2 bladed foldingprop though.
 
Interesting responses to my post: I reviewed previous posts on same subject and it seems saildrives are the worst, (esp. Volvo) and the gear teeth of Gori are criticized. Mine are in almost perfect condition, as are the blades apart from the pivot holes and faces in the slot. I had them re-bushed by Sillette-Sonic at 5000 hrs, but the bushes are almost gone after another 1000. From other's comments, my Gori seems to have done well, with no corrosion whatever. Maybe I expect too much of it, even if it did spend 90% of its time as a passenger for 47K miles! Thanks for the contributions.
 
It's as I said, there is stress corrossion where the blade rattles around the pin. Perhaps the gear teeth are a good fit
 
Interresting.. My boat is an Omega 36 with Yanmar 3GM30 and a shaft-mounted prop with anode. The original Alkometal (??) 2-blade folding prop lasted 14 years. Then one of the teeth broke off and the blades didn't always interlock correctly. 5 seasons ago I installed a Gori 2-blade prop. First season all was perfect,- second season I noticed increasing vibrations probably due to the blades wobbling. This season the blades seems to fail interlocking and I suspect the teeth is worn. (The boat is still in the water..) I asked the Norwegian importer of Gori props and they had neeeever heard about such a short life...
 
Re Athene: I now suspect that the difference between the long lives and early failures may be in the grease (or lack of it) in the hub. Gori do advise packing with waterproof grease on installation: perhaps we should do that every season, and neglect is the reason for short life?
 
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