Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 10-04-2016, 13:45   #1
Registered User

Join Date: Dec 2015
Posts: 15
Sailboat outboard prop - lower pitch always better?

Hi,

I have an old 2-stroke yamaha (5C) outboard from -87 on my 25' sailboat, which still runs fine. It has a 7 1/2 x 8 propeller, which is too a high pitch for a sailboat. In reverse, the traction is horrible and in forward the engine runs very heavy, with a blurry sound. This propeller looks like the shine one in the first picture.

Now, I have found a propeller with lower pitch (7 1/4 6 1/2), looks like the one in the second picture. From what I have understood, props for sailboat outboards generally have 1. lower pitch, 2. larger surface area, 3. often four blades.

The yamaha props with <7" pitch seem to all look like the second pic below. Smaller surface area. 1/4 inch smaller diameter.

Does anyone have an idea whether such a prop would actually provide more thrust?

Bonus question: found a manual online that says both type "-B" and "-BA" props will fit the 5C. Yet -B has pin drive, while -BA has splines and no pin socket. That can't work, can it?


masthugg is offline   Reply With Quote
Old 10-04-2016, 14:30   #2
Moderator
 
Jim Cate's Avatar

Join Date: May 2008
Location: cruising SW Pacific
Boat: Jon Sayer 1-off 46 ft fract rig sloop strip plank in W Red Cedar
Posts: 21,155
Re: Sailboat outboard prop - lower pitch always better?

In yor placeI would contact an aftermarket prop vendor such as SOLAS. They have a wide range of designs, including four blades, which can fit your motor, and they have the expertise to advise you on the choice. We were very happy with one for a very heavy inflatable some years ago... improved performance hugely over any of the stock Suzuki props that were available.

Jim
__________________
Jim and Ann s/v Insatiable II, lying Port Cygnet Tasmania once again.
Jim Cate is offline   Reply With Quote
Old 11-04-2016, 06:22   #3
Registered User

Join Date: Dec 2015
Posts: 15
Re: Sailboat outboard prop - lower pitch always better?

Quote:
Originally Posted by Jim Cate View Post
In yor placeI would contact an aftermarket prop vendor such as SOLAS. They have a wide range of designs, including four blades, which can fit your motor, and they have the expertise to advise you on the choice. We were very happy with one for a very heavy inflatable some years ago... improved performance hugely over any of the stock Suzuki props that were available.

Jim


I have barely been able to find any props that fit this old engine at all. But maybe a call is better than the internet when it comes to old stuff.
masthugg is offline   Reply With Quote
Reply

Tags
outboard, pitch, sail, sailboat

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Johnson 9.9 Outboard Prop Pitch? Svdestiny Engines and Propulsion Systems 7 25-04-2014 17:43
Prop Pitch on Dinghy By Invitation Propellers & Drive Systems 6 10-08-2012 04:10
Higher Prop Pitch/Lower RPM Nirvava Engines and Propulsion Systems 8 02-12-2010 17:25
For Sale: Kiwi Prop 18.5'' Variable Pitch TOM Classifieds Archive 0 02-09-2009 01:48
Prop Size and Pitch? ciclon1942 Propellers & Drive Systems 17 26-05-2009 05:50

Advertise Here


All times are GMT -7. The time now is 19:32.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.