www.iFourWinns.com

Dedicated to Current and Future Owners
It is currently Fri Mar 29, 2024 3:50 am

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 5 posts ] 
Author Message
 Post subject: Question about RPM's
PostPosted: Wed Jun 14, 2017 3:12 pm 
Offline
Dolphin

Joined: Thu Mar 02, 2017 9:11 am
Posts: 98
Location: Fort Pierre, SD
Ok, I'm a newbie when it comes to this. How do I know what the safe RPM range is for my boat? I can't find it listed in the manual. How is that affected by changing to a different propeller? I have a 2007 Horizon 210 with the carbureted 5.0 Mercruiser. I have the Alpha 1 outdrive and currently have a 21p 3 blade aluminum prop. I'm looking at changing to a 19p 4 blade stainless steel prop. I only run my boat at WOT when getting on plane, then back it off, but I'm not sure how many RPMs are too much and how many RPMs are too little. I certainly don't want to wear out my motor.

Thanks!

_________________
2007 Horizon 210
5.0 Mercruiser Carbureted/Alpha I
Image


Top
 Profile  
 
 Post subject: Re: Question about RPM's
PostPosted: Wed Jun 14, 2017 8:09 pm 
Offline
230 Mike
User avatar

Joined: Mon May 15, 2006 7:59 pm
Posts: 5141
Location: Kansas City, Table Rock Lake
Page 28.

http://www.fourwinns.com/uploads/2017/2 ... ts2007.pdf

This might help with understanding props. It helps if you visualize it spinning as it moves through a solid object:

http://www.boatingmag.com/how-to/unders ... ller-pitch

_________________
Image

Mike
2005 Four Winns 230/240
VP 5.7GXi/DP
1998 F-150 XLT
Boat Pic


Top
 Profile  
 
 Post subject: Re: Question about RPM's
PostPosted: Wed Jun 14, 2017 8:21 pm 
Offline
Dolphin

Joined: Thu Mar 02, 2017 9:11 am
Posts: 98
Location: Fort Pierre, SD
I must be blind, I'm not seeing the recommended/max RPM range. Also, that says I should be going 47mph at 4500 RPM. On a perfect day I might hit 41 at WOT trimmed up. Should I take that to mean something is wrong with my boat?

_________________
2007 Horizon 210
5.0 Mercruiser Carbureted/Alpha I
Image


Top
 Profile  
 
 Post subject: Re: Question about RPM's
PostPosted: Thu Jun 15, 2017 6:31 am 
Offline
Shark

Joined: Tue May 06, 2014 7:25 am
Posts: 145
Location: Ohio
If your current 3 blade prop allows you to hit max RPM the 4 blade you have selected should give you the same. You must go down in pitch when adding a blade.

_________________
2008 H200 Frenzy Edition 5.0 GXi

1993 Horizon 190 5.0 EFI (Sold)


Top
 Profile  
 
 Post subject: Re: Question about RPM's
PostPosted: Thu Jun 15, 2017 6:38 am 
Offline
268 Vista

Joined: Tue May 16, 2006 9:49 am
Posts: 4989
Location: West Michigan
Quote:
I'm not seeing the recommended/max RPM range


4400-4800 RPM.

https://www.perfprotech.com/blog/tech-s ... ifications

_________________
One of 4 Previous (Sold) Boats:
2000 Four Winns 268 Vista
Image
Current Boat: 2004 Chaparral 235 ssi cuddy
Image


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 5 posts ] 

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 6 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group