Logo
Results 1 to 2 of 2
  1. #1

    Question Low rpm at full throttle

    I have a mercury 40hp 4 stroke EFI (1000cc;4 cyl) with a 17 pitch propeller Black Max wth 3 blades and at full throttle I can only achieve 5000 rpm. The weight of the boat is 180kg and the boat is loaded with 2 persons. The recommended rpm for this motor is around 5500-6000. I feel that I loose some power with this low rpm. The actual speed at full throttle is 50km/h. What can I do to increase rpm. If I will increase rpm I will achieve a better speed?
    Last edited by stefancapatina; 06-29-2019 at 12:03 PM.

  2. #2
    Join Date
    May 2015
    Location
    Oregon
    Posts
    135

    Default Re: Low rpm at full throttle

    I don't think you'll make a big difference. For higher rpm either a smaller prop, less pitch, or some combination. To go faster, bigger motor or lighter boat.

Similar Threads

  1. Only Runs on Full Throttle and Full Choke, 9.9 Four Stroke 2012
    By Ericmck in forum Mercury Mariner Outboard Forum
    Replies: 0
    Last Post: 07-20-2015, 07:22 AM
  2. B100 Only Starts Full Choke and only runs Full Throttle? Help!!
    By jduck1 in forum Honda Outboard Forum
    Replies: 14
    Last Post: 04-12-2014, 12:51 AM
  3. Motor won't run at full throttle - Boggs down when full throttle
    By cbb174 in forum Mercury Mariner Outboard Forum
    Replies: 1
    Last Post: 07-05-2013, 04:45 PM
  4. 1968 20 hp johnson doesnt have full power at full throttle
    By phillipramsey in forum Johnson Evinrude Outboard Archive
    Replies: 6
    Last Post: 07-04-2009, 10:01 AM
  5. Replies: 2
    Last Post: 02-20-2006, 07:11 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •