I have newly acquired Trevi a 350 with hull number 461.
I am not happy with the 14x10 fixed prop, it appears to be underpropped in that the engine should max out at 3,000rpm at wide open throttle, but on our boat it gets to just over 3,200. At cruising rpm of 2,500 we get right at 6 knots in still water.
I am looking at a prop upgrade and KIWI prop have provided a recommendation for a 16.5x21 and the cost would be $1,500 including delivery.
They also provided a list of 6 other Catalina 350s that they have provided Kiwi props for and they claim that everyone has been happy! (no surprise there)
Has anyone on this forum fitted a Kiwi prop?
If so could you respond with the prop specs you have fitted and your experience. (prop walk?, boat speed at 2,500rpm etc)
I would also be interested in other folding/feathering options with specs but I am attracted to the Kiwi due to a rather reasonable cost.
Thanks
Trevor Rabie
Trevi #461
San Diego CA
Kiwi Prop anyone?
Moderator: KenKrawford
-
leigh weiss
- Posts: 208
- Joined: Mon Mar 05, 2012 7:32 pm
Re: Kiwi Prop anyone?
Trevor,
I fitted a KIWI Prop in 2010 to my C350 with a Universal M35B engine. The transmission is a 1.88:1 and I run at 2350- rpm. My wide open throttle rpm is 3000 under load in flat seas. No black smoke. Fuel consumption is about .5 gph at 2350. ( the sweet spot for specific fuel consumption for my engine) Traveled to New Englland from the Chesapeake each summer and one trip south for the winter. My results are consistent over the last 10 years. I adjusted the pitch in the water (a great feature) to load the engine to max rpm of 3000 at WOT to fine tune the prop. Prop walk and reverse thrust seem good. Added features of the KIWI prop are low mass and rearward offset placing the blades further aft away from the deadwood and further below the bottom of the boat. This completely eliminated prop cavitation noise I had from the original three blade prop. My sailing speed increased about .5 + knots and the prop shaft is left in neutral with no shaft turning.
I have some pix of the installed prop if you need them. I have a spare set of blades which can be fitted in the water but have never needed to replace one yet. (Cheap insurance).
Have a great time with your to you boat.
Leigh Weiss
I fitted a KIWI Prop in 2010 to my C350 with a Universal M35B engine. The transmission is a 1.88:1 and I run at 2350- rpm. My wide open throttle rpm is 3000 under load in flat seas. No black smoke. Fuel consumption is about .5 gph at 2350. ( the sweet spot for specific fuel consumption for my engine) Traveled to New Englland from the Chesapeake each summer and one trip south for the winter. My results are consistent over the last 10 years. I adjusted the pitch in the water (a great feature) to load the engine to max rpm of 3000 at WOT to fine tune the prop. Prop walk and reverse thrust seem good. Added features of the KIWI prop are low mass and rearward offset placing the blades further aft away from the deadwood and further below the bottom of the boat. This completely eliminated prop cavitation noise I had from the original three blade prop. My sailing speed increased about .5 + knots and the prop shaft is left in neutral with no shaft turning.
I have some pix of the installed prop if you need them. I have a spare set of blades which can be fitted in the water but have never needed to replace one yet. (Cheap insurance).
Have a great time with your to you boat.
Leigh Weiss
Leigh and Donna Weiss
Brisa #155
Georgetown, MD. USA
Brisa #155
Georgetown, MD. USA
Re: Kiwi Prop anyone?
I do not have a Kiwi prop, but was also not satisfied with the standard 14x10 fixed blade prop. I believe you are correct in that it is vastly underpropped. We installed a Gori folding prop last winter and I feel it is the best addition I have made to the boat other than adding solar panels.
I am not sure that you could fit a 16.5" prop under a Catalina 350. The reason they switched from the 15x9 prop was due to cavitation issues related to the 15" prop being too close to the deadwood and bottom of the hull. Also I can't imagine a 21" pitch on that sized prop for this boat. Something seems drastically wrong there.
The unique thing about the Gori prop is that it is a 2-speed prop. You can shift from a standard pitch to an overdrive pitch via controlling the throttle. We opted for the 15x10 standard pitch with provides an 'overdrive' pitch of about 15x12. It's a little pricey at $2500, but I would never go back to a non-overdrive prop again. The overdrive feature gives you the option of changing the pitch based on the conditions you happen to be sailing (or cruising) in.
Below is a chart I created of our performance with the standard prop and the Gori 15x10 shortly after installation and new bottom paint. RPMs were measured with a optical tachometer on the crank shaft and SOG measured via the GPS averaged from 2 runs in opposite directions. Keep in mind our boat is generally loaded to the gills with cruising gear and is generally much heavier than our friends Catalina 350 Mark II that I previously could not keep up with. Recently we cruised together and I was able to catch up from an hour behind over a 30-mile sailing leg. We typically now run around 6 knots at 2100 RPM in overdrive. Occasionally switch to the standard pitch and run WOT for a short period to manage any carbon build up that may develop by constantly running at lower RPM. On the downside, our fuel consumption has increased from around 0.65 gal/hour to around 0.80 gal/hour. However, since we are going about 20% faster, our MPG are essentially the same (First Law of Thermodynamics - the energy in the fuel is converted into energy of the boat motion).
I am not sure that you could fit a 16.5" prop under a Catalina 350. The reason they switched from the 15x9 prop was due to cavitation issues related to the 15" prop being too close to the deadwood and bottom of the hull. Also I can't imagine a 21" pitch on that sized prop for this boat. Something seems drastically wrong there.
The unique thing about the Gori prop is that it is a 2-speed prop. You can shift from a standard pitch to an overdrive pitch via controlling the throttle. We opted for the 15x10 standard pitch with provides an 'overdrive' pitch of about 15x12. It's a little pricey at $2500, but I would never go back to a non-overdrive prop again. The overdrive feature gives you the option of changing the pitch based on the conditions you happen to be sailing (or cruising) in.
Below is a chart I created of our performance with the standard prop and the Gori 15x10 shortly after installation and new bottom paint. RPMs were measured with a optical tachometer on the crank shaft and SOG measured via the GPS averaged from 2 runs in opposite directions. Keep in mind our boat is generally loaded to the gills with cruising gear and is generally much heavier than our friends Catalina 350 Mark II that I previously could not keep up with. Recently we cruised together and I was able to catch up from an hour behind over a 30-mile sailing leg. We typically now run around 6 knots at 2100 RPM in overdrive. Occasionally switch to the standard pitch and run WOT for a short period to manage any carbon build up that may develop by constantly running at lower RPM. On the downside, our fuel consumption has increased from around 0.65 gal/hour to around 0.80 gal/hour. However, since we are going about 20% faster, our MPG are essentially the same (First Law of Thermodynamics - the energy in the fuel is converted into energy of the boat motion).
- Gori Performance Chart.JPG (116.24 KiB) Viewed 1970 times
Gary & Janet
The Best of Times (Hull #422)
The Best of Times (Hull #422)
Re: Kiwi Prop anyone?
Leighleigh weiss wrote: ↑Sun Nov 08, 2020 8:14 am Trevor,
I fitted a KIWI Prop in 2010 to my C350 with a Universal M35B engine. The transmission is a 1.88:1 and I run at 2350- rpm. My wide open throttle rpm is 3000 under load in flat seas. No black smoke. Fuel consumption is about .5 gph at 2350. ( the sweet spot for specific fuel consumption for my engine) Traveled to New Englland from the Chesapeake each summer and one trip south for the winter. My results are consistent over the last 10 years. I adjusted the pitch in the water (a great feature) to load the engine to max rpm of 3000 at WOT to fine tune the prop. Prop walk and reverse thrust seem good. Added features of the KIWI prop are low mass and rearward offset placing the blades further aft away from the deadwood and further below the bottom of the boat. This completely eliminated prop cavitation noise I had from the original three blade prop. My sailing speed increased about .5 + knots and the prop shaft is left in neutral with no shaft turning.
I have some pix of the installed prop if you need them. I have a spare set of blades which can be fitted in the water but have never needed to replace one yet. (Cheap insurance).
Have a great time with your to you boat.
Leigh Weiss
Thanks for the positive response
What are the specs of your Kiwi prop?
Trevor
Re: Kiwi Prop anyone?
Hi there Trevor,
I fitted a Kiwi prop back in 2007 when my C350 was a year old. Night and Day difference in close quarters getting in and out of slips in the tidal condtions like we have here. I usually go into my tight spot with strong cross ways tides. If I go bow in, with incoming tide I get pushed away from the dock. But if I go in with a little speed, move to reverse and rev hard it snugs in sideways quickly and we can get tied up with no drama. It was just about impossible to do so with the factory Michigan prop. There is also another string in this forum about folding props including comments from me.
My factory invoice says it is a "Kiwi Feather Propeller KF3RH16.5x22x1" and cost me $ C1275 back then. I had them install it, cost included, in the US as we live just over the border from Canada. Initially it was overpropped/heating as shipped so on the next liftout, eased it off a 1/2 turn as I recall and it runs all day at 2800 rpm ( I have the only 350 with a factory Yanmar so far as I know) and can get it up to 3300 but it then goes close to overheating. Uses about 1 GPH at 2800. I think we eased it off a few years later a quarter turn. No black smoke and the engine now has about 2200 hours.
The other big advantage of Kiwi props: I had a Kiwi prop on my earlier C320. I hit an "invisible log" at 6 knots at dusk a few hundred miles up the coast and it broke off two blades. The shaft was bent as well. The new blades cost only about $300 for a set of 3 as I recall. Because of that lesson, on the C350 i had installed a "shaft saver" extension on the shaft just aft of the transmission - that would have stopped the shaft being bent. It adds about 2 inches to the shaft length which means one can have a donut zinc and not the conventional ball zinc which is a very tight fit. We dont have near as many logs around here any more - pulp mill log 8000t tows are almost all gone - but I still like the comfort factor. i have no cavitation issues.
Finally, after my C320 incident when keeping the old Michigan prop as a spare, I kept the factory Michigan on the 350 as a spare as well. A few years back I sold it for $300 on EBay. Took a while but a fishboat guy bought it. So that cost offset may be useful to you. If you wish to talk further send a reply with your phone number to my email at sail1942@hotmail.com. I would be pleased to hear from you.
Hope this helps, Geoff. S. C350, #392, Taeko 1V, Semiahmoo, Blaine, WA.
I fitted a Kiwi prop back in 2007 when my C350 was a year old. Night and Day difference in close quarters getting in and out of slips in the tidal condtions like we have here. I usually go into my tight spot with strong cross ways tides. If I go bow in, with incoming tide I get pushed away from the dock. But if I go in with a little speed, move to reverse and rev hard it snugs in sideways quickly and we can get tied up with no drama. It was just about impossible to do so with the factory Michigan prop. There is also another string in this forum about folding props including comments from me.
My factory invoice says it is a "Kiwi Feather Propeller KF3RH16.5x22x1" and cost me $ C1275 back then. I had them install it, cost included, in the US as we live just over the border from Canada. Initially it was overpropped/heating as shipped so on the next liftout, eased it off a 1/2 turn as I recall and it runs all day at 2800 rpm ( I have the only 350 with a factory Yanmar so far as I know) and can get it up to 3300 but it then goes close to overheating. Uses about 1 GPH at 2800. I think we eased it off a few years later a quarter turn. No black smoke and the engine now has about 2200 hours.
The other big advantage of Kiwi props: I had a Kiwi prop on my earlier C320. I hit an "invisible log" at 6 knots at dusk a few hundred miles up the coast and it broke off two blades. The shaft was bent as well. The new blades cost only about $300 for a set of 3 as I recall. Because of that lesson, on the C350 i had installed a "shaft saver" extension on the shaft just aft of the transmission - that would have stopped the shaft being bent. It adds about 2 inches to the shaft length which means one can have a donut zinc and not the conventional ball zinc which is a very tight fit. We dont have near as many logs around here any more - pulp mill log 8000t tows are almost all gone - but I still like the comfort factor. i have no cavitation issues.
Finally, after my C320 incident when keeping the old Michigan prop as a spare, I kept the factory Michigan on the 350 as a spare as well. A few years back I sold it for $300 on EBay. Took a while but a fishboat guy bought it. So that cost offset may be useful to you. If you wish to talk further send a reply with your phone number to my email at sail1942@hotmail.com. I would be pleased to hear from you.
Hope this helps, Geoff. S. C350, #392, Taeko 1V, Semiahmoo, Blaine, WA.
Geoff.S., Semiahmoo, WA.
Re: Kiwi Prop anyone?
So after reading these various posts and particularly the excellent post from Gary and Janet "Best of Times" I decided to take the plunge (deep into my wallet that is) and go with the GORI prop. I was given the same recommended specs ie 15x10 prop. I also sprang for Propspeed after reviewing the topic in Practical Sailor and had it professionally applied ($250). The prop itself was airfreighted direct from Denmark and the cost was right at $2700.
The performance improvement while motoring is immediately apparent and roughly follows the data in Gary's post. With the standard 14x10 I struggled to make 6knts at 2500 rpm, now getting right at 7knts at same revs but in overdrive and about 6.7 knts in standard drive.
I have only sailed with the new prop once but my sense is that the boat has picked up perhaps a 1/2 knt or so and appears to be pointing a little better too.
All in all, this was an expensive upgrade, but so far I am impressed.
Trevor
Trevi Hull #460
The performance improvement while motoring is immediately apparent and roughly follows the data in Gary's post. With the standard 14x10 I struggled to make 6knts at 2500 rpm, now getting right at 7knts at same revs but in overdrive and about 6.7 knts in standard drive.
I have only sailed with the new prop once but my sense is that the boat has picked up perhaps a 1/2 knt or so and appears to be pointing a little better too.
All in all, this was an expensive upgrade, but so far I am impressed.
Trevor
Trevi Hull #460
-
smcgauvran
- Posts: 1
- Joined: Sat Aug 07, 2021 8:30 pm
Re: Kiwi Prop anyone?
Trevor,
We are looking to purchase a Gori three blade for Hull 377. When I input my boat specs (M35B-C (35 HP at 3000 RPM) and Hurst 1.88 to 1), the manufacturer recommended a 15 X 12 prop, which, from other 350 posts, would seriously overprop the boat. Do you have the same engine/trans specs as above? If so, can you reach the 3000 rpm mark with the 15 X 10? Is it underpropped at that pitch?
Thanks, Mike
We are looking to purchase a Gori three blade for Hull 377. When I input my boat specs (M35B-C (35 HP at 3000 RPM) and Hurst 1.88 to 1), the manufacturer recommended a 15 X 12 prop, which, from other 350 posts, would seriously overprop the boat. Do you have the same engine/trans specs as above? If so, can you reach the 3000 rpm mark with the 15 X 10? Is it underpropped at that pitch?
Thanks, Mike
Re: Kiwi Prop anyone?
Mike,
My boat has the same engine/transmission with the 1.88 to 1 and I was recommended to get the 15x10 Gori prop, which by the way can go to 15x12 in overdrive.
In regular mode I can get to about 2800 rpm at WOT and the boat will get about 6.8knots at 2500 or so rpm in flat water.
So I agree with you that the 15x12 would definitely lead to an overprop situation.
Best
Trevor
Trevor C350 #460
My boat has the same engine/transmission with the 1.88 to 1 and I was recommended to get the 15x10 Gori prop, which by the way can go to 15x12 in overdrive.
In regular mode I can get to about 2800 rpm at WOT and the boat will get about 6.8knots at 2500 or so rpm in flat water.
So I agree with you that the 15x12 would definitely lead to an overprop situation.
Best
Trevor
Trevor C350 #460