Go Back  Offshoreonly.com > Technical > Prop Talk
4.3 mercruiser - 23 pitch 4 blade prop >

4.3 mercruiser - 23 pitch 4 blade prop

Notices

4.3 mercruiser - 23 pitch 4 blade prop

Thread Tools
 
Old 08-31-2017, 07:17 AM
  #1  
Registered
Thread Starter
 
Join Date: Aug 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default 4.3 mercruiser - 23 pitch 4 blade prop

Considering a 14 x 23 pitch prop (4 blade Aluminum Quicksilver Nemesis) for my 19 foot bowrider. The boat came with a 21 pitch 3 blade but the WOT easily goes beyond 4800 RPM. The 14 x 23 pitch I am considering seems to work perfectly: Max WOT at 4800 - Max speed at 50 MPH (best performance yet) - Best hole shot yet (225 lbs slalom waterskier). However, all the threads I have read suggest that a 4.3 merc should not be linked with a 23 pitch prop. Should I be concerned?
OLDSKIER is offline  
Old 08-31-2017, 07:35 AM
  #2  
Registered
 
Join Date: Feb 2012
Location: westville, NJ
Posts: 4,031
Likes: 0
Received 10 Likes on 8 Posts
Default

21 to 23 is roughly 10% WOT of 4800 will be reduced by 480 or so to 4320. That is too low. Lugging and overloading that small motor. What about a 22 prop? It wold top out about 4600. This is OSO. I gotta say it. Put a 350 in it...
dereknkathy is offline  
Old 08-31-2017, 09:36 AM
  #3  
BUP
Banned
iTrader: (9)
 
Join Date: Jul 2011
Location: Ft. Worth TX
Posts: 9,594
Likes: 0
Received 41 Likes on 35 Posts
Default

many rec boat brands 17.5 to 19 ft with Merc 4,3 V6 engines come with 23 pitch 3 blade props. Sea ray, Glastron, Larson, Tahoe, and so on and so on
BUP is offline  
Old 08-31-2017, 09:55 AM
  #4  
Registered
 
Join Date: Feb 2012
Location: westville, NJ
Posts: 4,031
Likes: 0
Received 10 Likes on 8 Posts
Default

How far past the 4800 does it rev? Cuz the engine is happier as the load is decreased. If it'll only rev to 4000, the load is too high at all rpms. What about a 3 blade 23?
dereknkathy is offline  
Old 08-31-2017, 09:57 AM
  #5  
Registered
 
Join Date: Feb 2012
Location: westville, NJ
Posts: 4,031
Likes: 0
Received 10 Likes on 8 Posts
Default

How far past the 4800 does it rev? Cuz the engine is happier as the load is decreased. If it'll only rev to 4400, the load is too high at all rpms. What about a 3 blade 23? Might be able to borrow one, instead of purchasing.
dereknkathy is offline  
Old 08-31-2017, 10:13 AM
  #6  
Registered
Thread Starter
 
Join Date: Aug 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default Boat performance with 23 pitch 4 blade

Tried my 2013 Campion 535i bowrider with a 14 x 23 pitch (4 blade) again today am am getting the following performances:
Got a max WOT at 4800 RPM
Max speed at 50 MPH...51 MPH
Best hole shot yet towing a 225 lbs slalom waterskier

These specs seem to tell me this is the best prop for my boat. I am VERY surprised since I had not heard of a 23 pitch 14 diameter prop on a 4.3 litre merc motor.

Last edited by OLDSKIER; 08-31-2017 at 10:26 AM. Reason: adding a blade spec (4 blade)
OLDSKIER is offline  
Old 08-31-2017, 10:26 AM
  #7  
Registered
 
Join Date: Jun 2011
Posts: 1,165
Received 110 Likes on 82 Posts
Default

What is your drive ratio?
Trash is offline  
Old 08-31-2017, 11:19 AM
  #8  
Registered
Thread Starter
 
Join Date: Aug 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

It is a 2013 535i Campion boat with a 4.3 merc. I suspect what comes standard for the lower unit with a 4.3 merc is the drive ratio ? Please tell me if it matters since the 23 pitch 4 blade works so well with the current set up. Thanks.
OLDSKIER is offline  
Old 08-31-2017, 11:43 AM
  #9  
Registered
 
Join Date: Feb 2012
Location: westville, NJ
Posts: 4,031
Likes: 0
Received 10 Likes on 8 Posts
Default

I believe it is a 1.62 or 1.68. If you are getting 4800 at WOT you aren't hurting the engine by lugging it. I was under the impression you were hitting 4800 with the 21 and wanted to run a 23.
dereknkathy is offline  
Old 08-31-2017, 12:02 PM
  #10  
Registered
Thread Starter
 
Join Date: Aug 2017
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

Hello DERIKnKATHY,
With the 14 x 23 pitch (4 blade) I am getting a max WOT at 4800 RPM, a max speed of 50-52 MPH and best hole shot yet towing a 225 lbs slalom waterskier. I was never able to get these specs with the 21 pitch 3 blade. My only question is you mention lugging. Motor feels very powerful pulling me out, planes very fast also, even when pulling me out of the water on one ski. The max RPM is now at 4800... With the 21 pitch I could easily get 5200...which was above WOT RPM. I do not sense any lugging at any time with the 23. Hope I am writing the specs correctly as i do not want to be lugging the motor or having the wrong prop. Thanks again for the follow up. Quite possibly, the Campion 535i bowrider is a light boat.
OLDSKIER is offline  


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.