Reply
 
Thread Tools Search this Thread
 
Old 08 March 2007, 15:22   #1
Member
 
Country: UK - Scotland
Town: Ayrshire
Boat name: Raven
Make: Ribcraft
Length: 5m +
Engine: 150 suzuki
MMSI: 235040525
Join Date: Aug 2006
Posts: 654
3 blade to 4 blade

Has anyone changed from a 3 bladed prop to a 4 blader,why, and did they notice any decernable difference? I'm trying to achieve better bow lift, when trimmed out, I find someone moving forward will bring the hull down into contact with the water,lowering the speed. I've done a little research and maybe going from three to four might give better control..i'm just guessing at the moment. Does anyone have experience of this problem,has anyone solved it by other means? I'm keen to learn here.
__________________
.
IBWET is offline   Reply With Quote
Old 08 March 2007, 16:04   #2
Member
 
Country: USA
Town: Oakland CA
Length: 3m +
Join Date: Feb 2005
Posts: 6,653
I was under the impression that a 4-blade promoted better stern lift. Helps to get on-plane quicker due to the larger surface area pushing water.

All things being equal (pitch, diameter, general blade shape) expect to lose a couple hundred rpm adding the extra blade. And a few mph off the top end at the same rpm. You should get more efficient cruise fuel economy, though.

jky
__________________
jyasaki is offline   Reply With Quote
Old 08 March 2007, 23:27   #3
Member
 
Country: Ireland
Town: Dublin & Enniscrone
Boat name: K'adó
Make: Redbay
Length: 7m +
Engine: Suzuki 300
Join Date: Oct 2004
Posts: 613
ditto results

Did it last year.

Better acceleration
Lost a few knots at wot.
better economy at mid range.
Much better prop grip in rough weather with subsequent better responsivness
more economical when carryingheavy loads

enjoy
__________________
Take it easy ....but, take it all the way.
Ezgoing is offline   Reply With Quote
Old 09 March 2007, 06:27   #4
Member
 
Country: UK - Scotland
Town: Ayrshire
Boat name: Raven
Make: Ribcraft
Length: 5m +
Engine: 150 suzuki
MMSI: 235040525
Join Date: Aug 2006
Posts: 654
Cheers,

Pretty much what I thought.


zero'd i on the Powertech 4 blader 15 1/4x24 OFS series (current one is 14 1/2 x25) the american bass boat forums tend to steer towards this manufacturer as the best.

Importing form the states, half the dosh...if it doesn't work though..








Quote:
Originally Posted by Ezgoing View Post
Did it last year.

Better acceleration
Lost a few knots at wot.
better economy at mid range.
Much better prop grip in rough weather with subsequent better responsivness
more economical when carryingheavy loads

enjoy
__________________
.
IBWET is offline   Reply With Quote
Old 09 March 2007, 06:34   #5
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: Dominator
Make: SR5.4
Length: 7m +
Engine: Yam 85
MMSI: 235055163
Join Date: Jul 2005
Posts: 13,069
RIBase
Quote:
Originally Posted by IBWET View Post
if it doesn't work though..
Then you sell it on Ebay and make a profit

Win-win situation.
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 09 March 2007, 07:08   #6
Member
 
Country: UK - Scotland
Town: Ayrshire
Boat name: Raven
Make: Ribcraft
Length: 5m +
Engine: 150 suzuki
MMSI: 235040525
Join Date: Aug 2006
Posts: 654
up early this morn nos,

Not being an e bayer I'd probably balls it up

Am I seeing "Prince of Darkness imports" on the horizon ?.



Quote:
Originally Posted by Nos4r2 View Post
Then you sell it on Ebay and make a profit

Win-win situation.
__________________
.
IBWET is offline   Reply With Quote
Old 10 March 2007, 08:30   #7
Member
 
Country: USA
Town: Oakland CA
Length: 3m +
Join Date: Feb 2005
Posts: 6,653
Quote:
Originally Posted by Nos4r2 View Post
Then you sell it on Ebay and make a profit
Win-win situation.
Personally, I'd toss the prop and some cash at a prop shop and get it tuned the way you want.

jky
__________________
jyasaki is offline   Reply With Quote
Old 10 March 2007, 08:47   #8
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: Dominator
Make: SR5.4
Length: 7m +
Engine: Yam 85
MMSI: 235055163
Join Date: Jul 2005
Posts: 13,069
RIBase
Quote:
Originally Posted by IBWET View Post
up early this morn nos,

Not being an e bayer I'd probably balls it up

Am I seeing "Prince of Darkness imports" on the horizon ?.
You would if I could get away with it but the import duty payable on lots of large items from the USA makes it non-viable and the fines are horrendous.
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 10 March 2007, 22:48   #9
Member
 
Hightower's Avatar
 
Country: UK - England
Town: Fareham
Length: 6m +
Join Date: Sep 2003
Posts: 7,866
Quote:
Originally Posted by Nos4r2 View Post
You would if I could get away with it but the import duty payable on lots of large items from the USA makes it non-viable and the fines are horrendous.
Not if you bring it home in your check in luggage like I've just done with an entire Sea Star Steering system
__________________
Andy

Looks Slow but is Fast
Member of the ebay Blue RIB cover club.
Hightower is offline   Reply With Quote
Old 10 March 2007, 22:56   #10
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: Dominator
Make: SR5.4
Length: 7m +
Engine: Yam 85
MMSI: 235055163
Join Date: Jul 2005
Posts: 13,069
RIBase
Quote:
Originally Posted by Hightower View Post
Not if you bring it home in your check in luggage like I've just done with an entire Sea Star Steering system
That only works if you can blag free flights
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 10 March 2007, 23:02   #11
Member
 
Hightower's Avatar
 
Country: UK - England
Town: Fareham
Length: 6m +
Join Date: Sep 2003
Posts: 7,866
I'll give you a shout next time I go. Yamaha F150 for $11500 anyone?
__________________
Andy

Looks Slow but is Fast
Member of the ebay Blue RIB cover club.
Hightower is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




All times are GMT. The time now is 05:46.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.