Flex-O-Fold Propellers vs Kiwi

[Strygaldwir]

I wonder why we don't safety wire the prop cones to the shaft?? I have sail-drives, fixed props. Once while diving my props I noticed that the center Allen bolt that is supposed to assure the prop cone doesn't come of was gone on one engine. I guess it would have only been a matter of time before I lost a prop. Made me do two things. I won't throw away my extra, beat up fix props. I'll keep them as spares. I'll get another spare cone. I have extra Allen bolts. I'll think about drilling for safety wire.

[veda]

just finished surveying a catamaran yesterday in florida. owner reported that one of his kiwi props fell off. he reported that the prop is held on solely with waterproof Loctite.

[fstbttms]

Originally Posted by veda

just finished surveying a catamaran yesterday in florida. owner reported that one of his kiwi props fell off. he reported that the prop is held on solely with waterproof Loctite.

Not precisely true. The set screws that secure the prop nut are Loctited on. There is no cotter pin or other mechanical fail-safe. But this is true of most feathering props.

[Katiusha]

We switched from Kiwi to Flex-o-Fold. Kiwi props weren't supplied with Loctite, so you could put whatever you wanted there. And if I understand correctly, the waterproof Loctite must be fully cured before getting into contact with water.

Flex-o-fold bolts were supplied with pre-applied waterproof Loctite, which specifically allows for underwater installation.

[HueyHuey]

Can I please ask for an update from anyone who has been using a Kiwi prop.

I own an Australian built Perry 43 catamaran running Yanmar 47 hp turbo motors with sail drives. My props are 3 blade fixed but are over sized preventing me from achieving full revs, fuel economy is good down low ie upto around 1500 rpm but can't get past 2200 with a ton of smoke to boot. Rebuilt engines but still can't get higher.

I am now looking at replacing the props with either Kiwi or Hydralign made in Australia.

The kiwi props win out on cost, but I just want to be sure it's not a false economy, you don't buy new props every day.

By the way, we live aboard and sail when we can, but quite often tend to run 1 motor just to help give us an extra couple of knots when the wind is light.

[jbinbi]

I had them for 4 years. Not as dependent as you on them, mostly day sailing a 37 mono. No issues buy to clean barnacles every fall.

[mrohr]

I need to muddy these waters (pun).
My aperture will only allow a 15" prop; now a 3 blade on a 1" shaft and no room for anything folding. So the only feathering prop that I'm aware of is the British Darglow, what know you all regarding Darglow and are there any others that might accommodate me?
Thanks in advance………………mike…………………………………………..

[autumnbreeze27]

I put one on my Catalina 34, upgrading from a fixed 3 blade.

PROS: We won races, motoring performance did not change, boat did not have significant prop walk in reverse

CONS: Putting the boat into reverse, the reversing of the blades would cause the boat to stall.

Huey you are overpropped which is bad for the engine. When I ordered my Kiwi, the guy in NZ was able to ask me questions about engine/hp/tranny/shaft size/etc to get you dialed in. At least he did a good job for me, except for the reverse issue mine was bolt on and go.

Originally Posted by HueyHuey

Can I please ask for an update from anyone who has been using a Kiwi prop.

I own an Australian built Perry 43 catamaran running Yanmar 47 hp turbo motors with sail drives. My props are 3 blade fixed but are over sized preventing me from achieving full revs, fuel economy is good down low ie upto around 1500 rpm but can't get past 2200 with a ton of smoke to boot. Rebuilt engines but still can't get higher.

I am now looking at replacing the props with either Kiwi or Hydralign made in Australia.

The kiwi props win out on cost, but I just want to be sure it's not a false economy, you don't buy new props every day.

By the way, we live aboard and sail when we can, but quite often tend to run 1 motor just to help give us an extra couple of knots when the wind is light.

[HueyHuey]

Thanks Autumnbreeze27, when you say the boat stalls, do you every time you select reverse the motors stall?
If so how do you manage with maneuvering in tight spots ie docking, etc.
If you were to replace them would you still buy kiwi or try perhaps a different brand where the blades aren't locked in to max Pitch?
What about maintenance, did you find that easy to Do?
Thanks again.

[daletournier]

Hi, lve had kiwi prop linked to my 3gm30f Yanmar for 1000 hrs now. The stalling that is mentioned is when the prop isn't greased properly thus blades not opening fully in reverse overloading engine. Fortunately I have a hookah dive system which enables me to grease them regularly therefore don't have overloading problem. Over all happy with prop, drives the boat very well. Have damaged blades and had to replace then recently. In fairness the damage is a result of a lot of rubbish in the malacca straight. If it wasn't the blades it could of been the coupling or worse. John at kiwi prop is great to deal with and knows his stuff.
Cheers Dale.

[autumnbreeze27]

It would not stall every time, and I got good at finessing it so it wouldn't stall, but it would still stall, and we'd tell people if it stalls on the way into the slip to jump out and stop her. I would also pull in very slowly so I'd have time to restart the motor if necessary. Typically if I was pulling out of the slip it might stall the first time I shifted into reverse.

We did a Christmas parade and it was a real problem keeping station (especially when some big powerboater would decide to use both engines to turn in place), so I'd just pass them versus risk stalling the boat and hitting them.

I only had the prop on the boat a year or so before selling it, so I can't tell you about longevity or maintenance.

I did a lot of research about them before buying, and the stalling in reverse was a common problem. I've never heard that greasing anything would fix it. I learned to deal with it by knowing it could happen, and finessing the throttle and shifter.

Here is a video the divers shot after they installed it. I run it forward and reverse (without stalling)

Kiwi Prop on 1991 Catalina 34 - YouTube

Would I buy one again? You betcha. We have a 50' cruiser and I was hoping to put one on that (probably until I saw how much it cost) but when I asked Kiwi they didn't make one big enough.

Lastly, I'd say if I was at the helm the chance of a stall in reverse was about 25%. Somebody who wasn't familiar with the boat, probably 50%. The boat never stalled shifting into reverse before, but I suspect that condition of your tranny and engine probably plays a part. If I had the tranny rebuilt the problem might not have been so bad or gone away completely, but we decided to buy a bigger boat instead

Originally Posted by HueyHuey

Thanks Autumnbreeze27, when you say the boat stalls, do you every time you select reverse the motors stall?
If so how do you manage with maneuvering in tight spots ie docking, etc.
If you were to replace them would you still buy kiwi or try perhaps a different brand where the blades aren't locked in to max Pitch?
What about maintenance, did you find that easy to Do?
Thanks again.

[belizesailor]

Recently installed Kiwi Props. Old props were 3 blade fixed.

Splashed today and did a short test run. Went well.

No virbrations or odd noises.

Forward speed/thrust about the same.

More thrust in reverse. No stalling.

Looking forward to testing under sail.

[mikereed100]

After several years with my Kiwiprops, I think the thing I like most about them is how easy they are to remove. Loosen 2 set screws and when you remove the nut it pulls the prop off the shaft at the same time. Very easy to do in the water (keep an eye on the key and tie a fender to the prop) and you never need a prop puller again.

[Neptune's Gear]

I did about 20,000 miles with a kiwiprop. You MUST lubricate ALL the lubrication points, and make sure the reversing rollers are free to rotate. If its not all lubricated they can cause the stall going into reverse, or jambing in reverse. They are a great prop, and won't "fall off" if properly fitted in the first place. The blades are way tougher than you think - really only being damaged when a metal blade would. Great product, great support!

Sent from my Nexus 7 using Cruisers Sailing Forum mobile app

[belizesailor]

Originally Posted by mikereed100

After several years with my Kiwiprops, I think the thing I like most about them is how easy they are to remove. Loosen 2 set screws and when you remove the nut it pulls the prop off the shaft at the same time. Very easy to do in the water (keep an eye on the key and tie a fender to the prop) and you never need a prop puller again.

I like the idea of the additional set screws secured w thread locker. I've never spun off a standard Volvo prop but many others have.