Cantata
Well-Known Member
Anyone with a Kiwiprop fitted to a boat based in a mud berth? If so, any problems?
Kiwiprops and Mud
- Thread starter Cantata
- Start date
FullCircle
Well-Known Member
Kiwiprop recommend not to be used in mud berth. But that would be true of any company making props, as mud berths are like putting in valve grinding paste.
I have been drying mine out for a long while now (6 years).
You must grease the body until grease spurts out of every orifice and mating surface. This will exclude a lot of the mud and silt, not to mention barnacles, which will make the mech slow then jam, evidenced by massive prop kick and no power in reverse, because the blades are like flat on paddles in jammed reverse mode.
The blades are also jammed with grease, although I am not certain if this is good, as it slows the response of the blades to flop about because it introduces a bit of friction.
Better that than full of mud though.
So, my blades now swing a bit more slowly than when new, but it does work, but can be a bit temperamental after 6-7 months without attention. If you scrub mid season, just grease the whole plot and it will be OK.
I have not noticed much wear in body mech or blade to spigot, and I have nearly 800 hours motoring on mine.
As an aside, I have broken a blade, about 30 mm chunk from top, but it all still worked, but with vibration. I faired it off and continued using it for a couple of months.
I now carry a spare blade and a couple of the retaining pins too.
Met Alan Pollard for the first time yesterday, what a nice bloke.
I have been drying mine out for a long while now (6 years).
You must grease the body until grease spurts out of every orifice and mating surface. This will exclude a lot of the mud and silt, not to mention barnacles, which will make the mech slow then jam, evidenced by massive prop kick and no power in reverse, because the blades are like flat on paddles in jammed reverse mode.
The blades are also jammed with grease, although I am not certain if this is good, as it slows the response of the blades to flop about because it introduces a bit of friction.
Better that than full of mud though.
So, my blades now swing a bit more slowly than when new, but it does work, but can be a bit temperamental after 6-7 months without attention. If you scrub mid season, just grease the whole plot and it will be OK.
I have not noticed much wear in body mech or blade to spigot, and I have nearly 800 hours motoring on mine.
As an aside, I have broken a blade, about 30 mm chunk from top, but it all still worked, but with vibration. I faired it off and continued using it for a couple of months.
I now carry a spare blade and a couple of the retaining pins too.
Met Alan Pollard for the first time yesterday, what a nice bloke.
Cantata
Well-Known Member
Ha! So you have one, Jim. I met Alan too, as you say a very nice bloke.
When I asked him about mud he sucked his teeth a bit as you might expect. But when he talked through how it works you could see that if it's stuffed full of grease (and perhaps replenished half way through the season) then the mud shouldn't get in.
When I asked him about mud he sucked his teeth a bit as you might expect. But when he talked through how it works you could see that if it's stuffed full of grease (and perhaps replenished half way through the season) then the mud shouldn't get in.
FullCircle
Well-Known Member
Dick, my report from 2006.....
Kiwiprop
Installation
2005 Jeanneau Sun Odyssey 35, Lifting keel, Twin Rudders, Yanmar 3YM30 engine with 2.62:1 reduction, LH.
Vessel is always loaded for cruising, and is thus low in the water,
http://i4.photobucket.com/albums/y12...u/Kiwiprop.jpg
Purchase price £795+vat all sizes
Documentation prior to delivery:
4 page diagrammatic requesting all vessel required details, and also current prop.
Simple, clear concise, no specialist knowledge required
Communication prior to delivery.
Order confirmation call,
Order despatch call., request if the greasing kit required.
Delivery
On time, with greasing kit (optional).
Robust packaging
Instructions
Owners Documentation, fitting instructions and warranty cert details included, in plastic sealed wallet.
Good photographs and details. Simple, clear concise, no specialist knowledge required
However, this could be improved if a clear acetate protractor template was included to be able to check blade angles.
Construction
Good quality stainless machinings to an acceptable finish. End stop faces for blade adjustment are not a machined surface, appearing to be an as forged condition. Tolerance not known, but appear to be similar for each of the 3 faces.
Blades are preassembled to hub and cut to length for arc of swing. Blades are factory adjusted for calculated best performance angles.
Blades appear to be uniform within a good plastic tolerance. Not individually weighed.
Grub screws for adjustment, and bush pins for blade retention appear to be of good quality.
Bush pins are an interference fit in the Zytel blades, passing through a machined shoulder in the blade hub spigots. These are robust, as I changed my blades. No looseness.
Retention hub for unit is good quality, and locking allen key feature is good fit to tool.
No prop mounted anode (standard on Jeanneau fit)
Installation
Removal of existing propeller took longer than installing new one.
Tapered hole in hub, keyways and keys good alignment fit.
Hub retention lock fitted and the unit locked at correct point on the shaft at top of taper.
Supplied grease was used, no issue.
Added extra grease to blade spigot nipples, all blades free to rotate about spigots, no binding.
Total installation time, less then 10 minutes with checks.
Note: I installed an Ambassador Stripper at the same time, which required a 10mm spacer in the shaft joint to gearbox. All items interfaced well.
Antifouling.
I used International Trilux, 3 coats.
Instructions advise not to cover screw adjustment faces.
After 8 weeks, some barnacle on the stainless areas, but not on the blades. (River Crouch, high fouling year)
After 8 weeks, blades free to rotate to correct angles.
1st Performance trial, motoring
Initial bite going into forward gear is a bit slower than 2 blade fixed (Standard Radice 16x13). More engine revs needed to start acceleration. Back off after reaching steerage speed, probably 2 secs difference.
Logged performance using differential runs upriver and downriver on a very light airs day, no more than 3 knots true.
Using Log speed and SOG on GPS in 2 directions at 2000, 3000, and 3650RPM
At 2000 the 3 blade was 0.6kts slower than fixed
At 3000 the 3 blade was 0.8kts slower than fixed
At 3650 the 3 blade was 0.9kts slower than fixed
Reverse bite is very quick, better than fixed. Much reduced propwalk. Performance in reverse limited to 5.5kts as the wave entered the cockpit through the sugar scoop transom. More available for the brave/foolhardy. This design engages full maximum blade pitch in reverse as there is no blade angle adjustment for reverse.
1st Performance trial, sailing
Very good in light airs tacking, allowing much improved acceleration out of tacks
In 10 knots upwind, performance improved approx 0.25 knots.
Downwind similar performance increase.
No noise, vibration or propshaft rotation observed.
After trial, Vectamarine contacted to discuss performance. We agreed an increase of 1 degree to 23 degrees, and an increase to 16.5” from 16”. Blades were manufactured and despatched at no further cost, in approx 4 days. The data programme possibly did not take into account my hull form and keel arrangement.
Unit was dissembled using small hammer and 5mm punch after drying out on local beach. 3 blades removed and replaced in 90 seconds.
Forgot the protractor, so relied on visual chaeck of blade angles. (Bad idea as it turns out).
2nd Performance trial, motoring
Initial bite going into forward gear is a bit slower than 2 blade fixed (Standard Radice 16x13). More engine revs needed to start acceleration. Back off after reaching steerage speed, probably 2 secs difference. No change from 1st trial
Logged performance using differential runs upriver and downriver on a light airs day, no more than 5 knots true.
Using Log speed and SOG on GPS in 2 directions at 2000, 3000, and 3650RPM
At 2000 the 3 blade was 0.3kts slower than fixed
At 3000 the 3 blade was 0.5kts slower than fixed
At 3650 the 3 blade was 0.5kts slower than fixed
Small vibration observed, probably due to poor alignment of blades post change. No opportunity to correct alignment yet.
Probably performance will equal the fixed blade after correction
2nd Performance trial, sailing
As 1st trial. Impressive.
Observations
No dissimilar metals in shaft/prop assembly. Good for corrosion prevention.
No gearbox or other moving parts to go wrong
Zytel blades are damage/impact resistant but have good elastic qualities.
Simple greasing as maintenance.
Needs clear plastic purpose made protractor to quickly check angles of operation.
Excellent sailing performance
Equivalent motoring performance.
Excellent value for money
Only available up to 55hp engine use
UK concessionaire excellent service
Kiwiprop
Installation
2005 Jeanneau Sun Odyssey 35, Lifting keel, Twin Rudders, Yanmar 3YM30 engine with 2.62:1 reduction, LH.
Vessel is always loaded for cruising, and is thus low in the water,
http://i4.photobucket.com/albums/y12...u/Kiwiprop.jpg
Purchase price £795+vat all sizes
Documentation prior to delivery:
4 page diagrammatic requesting all vessel required details, and also current prop.
Simple, clear concise, no specialist knowledge required
Communication prior to delivery.
Order confirmation call,
Order despatch call., request if the greasing kit required.
Delivery
On time, with greasing kit (optional).
Robust packaging
Instructions
Owners Documentation, fitting instructions and warranty cert details included, in plastic sealed wallet.
Good photographs and details. Simple, clear concise, no specialist knowledge required
However, this could be improved if a clear acetate protractor template was included to be able to check blade angles.
Construction
Good quality stainless machinings to an acceptable finish. End stop faces for blade adjustment are not a machined surface, appearing to be an as forged condition. Tolerance not known, but appear to be similar for each of the 3 faces.
Blades are preassembled to hub and cut to length for arc of swing. Blades are factory adjusted for calculated best performance angles.
Blades appear to be uniform within a good plastic tolerance. Not individually weighed.
Grub screws for adjustment, and bush pins for blade retention appear to be of good quality.
Bush pins are an interference fit in the Zytel blades, passing through a machined shoulder in the blade hub spigots. These are robust, as I changed my blades. No looseness.
Retention hub for unit is good quality, and locking allen key feature is good fit to tool.
No prop mounted anode (standard on Jeanneau fit)
Installation
Removal of existing propeller took longer than installing new one.
Tapered hole in hub, keyways and keys good alignment fit.
Hub retention lock fitted and the unit locked at correct point on the shaft at top of taper.
Supplied grease was used, no issue.
Added extra grease to blade spigot nipples, all blades free to rotate about spigots, no binding.
Total installation time, less then 10 minutes with checks.
Note: I installed an Ambassador Stripper at the same time, which required a 10mm spacer in the shaft joint to gearbox. All items interfaced well.
Antifouling.
I used International Trilux, 3 coats.
Instructions advise not to cover screw adjustment faces.
After 8 weeks, some barnacle on the stainless areas, but not on the blades. (River Crouch, high fouling year)
After 8 weeks, blades free to rotate to correct angles.
1st Performance trial, motoring
Initial bite going into forward gear is a bit slower than 2 blade fixed (Standard Radice 16x13). More engine revs needed to start acceleration. Back off after reaching steerage speed, probably 2 secs difference.
Logged performance using differential runs upriver and downriver on a very light airs day, no more than 3 knots true.
Using Log speed and SOG on GPS in 2 directions at 2000, 3000, and 3650RPM
At 2000 the 3 blade was 0.6kts slower than fixed
At 3000 the 3 blade was 0.8kts slower than fixed
At 3650 the 3 blade was 0.9kts slower than fixed
Reverse bite is very quick, better than fixed. Much reduced propwalk. Performance in reverse limited to 5.5kts as the wave entered the cockpit through the sugar scoop transom. More available for the brave/foolhardy. This design engages full maximum blade pitch in reverse as there is no blade angle adjustment for reverse.
1st Performance trial, sailing
Very good in light airs tacking, allowing much improved acceleration out of tacks
In 10 knots upwind, performance improved approx 0.25 knots.
Downwind similar performance increase.
No noise, vibration or propshaft rotation observed.
After trial, Vectamarine contacted to discuss performance. We agreed an increase of 1 degree to 23 degrees, and an increase to 16.5” from 16”. Blades were manufactured and despatched at no further cost, in approx 4 days. The data programme possibly did not take into account my hull form and keel arrangement.
Unit was dissembled using small hammer and 5mm punch after drying out on local beach. 3 blades removed and replaced in 90 seconds.
Forgot the protractor, so relied on visual chaeck of blade angles. (Bad idea as it turns out).
2nd Performance trial, motoring
Initial bite going into forward gear is a bit slower than 2 blade fixed (Standard Radice 16x13). More engine revs needed to start acceleration. Back off after reaching steerage speed, probably 2 secs difference. No change from 1st trial
Logged performance using differential runs upriver and downriver on a light airs day, no more than 5 knots true.
Using Log speed and SOG on GPS in 2 directions at 2000, 3000, and 3650RPM
At 2000 the 3 blade was 0.3kts slower than fixed
At 3000 the 3 blade was 0.5kts slower than fixed
At 3650 the 3 blade was 0.5kts slower than fixed
Small vibration observed, probably due to poor alignment of blades post change. No opportunity to correct alignment yet.
Probably performance will equal the fixed blade after correction
2nd Performance trial, sailing
As 1st trial. Impressive.
Observations
No dissimilar metals in shaft/prop assembly. Good for corrosion prevention.
No gearbox or other moving parts to go wrong
Zytel blades are damage/impact resistant but have good elastic qualities.
Simple greasing as maintenance.
Needs clear plastic purpose made protractor to quickly check angles of operation.
Excellent sailing performance
Equivalent motoring performance.
Excellent value for money
Only available up to 55hp engine use
UK concessionaire excellent service