Please note this thread has been inactive for 90 days. For the best results, please start a new thread.
Results 1 to 8 of 8
  1. #1
    Petty Officer 2nd Class
    Join Date
    Oct 2010
    Location
    Scio, Or.
    Posts
    179

    Default Rev limiter questions

    Does my 04 larson 230, which is equipped with a 5.0 GXI Volvo penta setup have one?? How do I know when it kicks in?

    Background; I have been working with a prop manufacturer to get me a custom SS 4 blade lab finished prop. In my latest round of testing, I was attempting to see how many RPM's the prop would allow me to run. WOT is listed as 4800-5000. At 5300 I noticed a slight cutout in the engine. Was this my rev limiter? It coincidentally would not go any faster. In my first round of testing, I backed out of the throttle at what I thought was 5400.

    I thought all newer boats were equipped with rev limiters. Is that limit 300 over max WOT???

    Confused?!?!
    Quote Originally Posted by newbie4life View Post
    "Everyone's an a** except for me and you... and I'm not so sure about you."


    2004 Larson 230LXI W/VP 5.0 AKA [COLOR=#00ff00]Mr Toads Wild Ride
    2003 Dodge ram 2500 W/5.9 Diesel-6spd manual

  2. #2
    Seaman Apprentice
    Join Date
    Aug 2012
    Posts
    41

    Default Re: Rev limiter questions

    WOT and your rev limiter are two different things, WOT is with a load (prop) and the range at which your motor will is most efficient. you want the prop to allow your rpms to fall into this range when the throttle is wide open. the rev limiter is there to keep you from blowing your motor up and protect the accessories such as alternator, power steering, etc.

  3. #3
    Ensign
    Join Date
    Jun 2010
    Location
    South Metro, MN
    Posts
    996

    Default Re: Rev limiter questions

    I'm betting you do have a rev limiter, and that's likely what was causing the slight miss at 5300. Your WOT range of 4800-5000 rpm is your target, not a hard rev limit. As you've seen, you can exceed this range if you under prop, or shove the throttle with the drive disengaged, etc... , the rev limiter kick in to keep the engine from running over it's limit. Not sure how far over the upper end of the WOT range is your red line. Now that you mention it, I don't know what my boat's red line is either. Also, your boat's tachometer could be off by a margin so the 5300 or 5400 your tach was indicating might be off.

  4. #4
    Vice Admiral Tail_Gunner's Avatar
    Join Date
    Jan 2006
    Location
    Portland, Or.
    Posts
    5,383

    Default Re: Rev limiter questions

    Your rev limiter is preset at 4950 rpm. Your tach is off by 250 rpm at 4950 it will shut off the fuel supply creating a lean burn so do not spend much time there. Vortec engine's run out of air at that point..(head cam design) so prop to 48-49...It sounds like a minute miss at wot.
    Stickly a opinion your milage may vary.

    Speed is how fast you hit the wall
    Torque is how far you move the wall"

  5. #5
    Honorary Moderator Emeritus Don S's Avatar
    Join Date
    Aug 2004
    Location
    Western WA.
    Posts
    62,323

    Default Re: Rev limiter questions

    The rev limiter is an internal part of the ECM, it's set to stop fuel injectors from working until the rpm is at or below the set limit. It's normally set to 200 rpm over the max rpm of your engine range, in this case 4600 to 5000 rpm. Which would make your rev limiter starting at 5200 rpm.
    Don S.


    Please, no PM's (Private Messages) regarding boat/engine problems.
    That is what the forums are for.
    Only forum/moderator issues will be answered in PM's.

  6. #6
    Moderator QC's Avatar
    Join Date
    Mar 2005
    Location
    Chino Hills, CA
    Posts
    22,045

    Default Re: Rev limiter questions

    Good thing all posts are in agreement as always . . .

    TG,

    Where'd you find 4950? Seems odd to be lower than recommended WOT range

  7. #7
    Vice Admiral Tail_Gunner's Avatar
    Join Date
    Jan 2006
    Location
    Portland, Or.
    Posts
    5,383

    Default Re: Rev limiter questions

    Quote Originally Posted by QC View Post
    Good thing all posts are in agreement as always . . .

    TG,

    Where'd you find 4950? Seems odd to be lower than recommended WOT range

    My laptop of course uisng a mefiburn program....But he does have a v8 and most importantly the Oracle has spoken....And so it is.....Hey 50 isnt bad its a monday geesh...
    Stickly a opinion your milage may vary.

    Speed is how fast you hit the wall
    Torque is how far you move the wall"

  8. #8
    Petty Officer 2nd Class
    Join Date
    Oct 2010
    Location
    Scio, Or.
    Posts
    179

    Default Re: Rev limiter questions

    So.....I understand and agree that the Tach could be/probably is not completely accurate. 5200 sounds correct since I was reading 5300+ or - when I was feeling the 'miss'. Okay, so I feel reasonably sure I understand this.

    Talked to my boat mechanic today, and he will run a tach check on it when we winterize(Yeah I said it!!!! suck suck suck) in a few weeks.

    My plan is to prop to 4800, prop guy assured me he could take all factors and plug them into his 'program' and create the perfect prop. So far 2 runs, and were still overpropped. On the plus side, I really like the feel of the SS prop. I'm sending it back to be re-worked, and hopefully we get it closer.
    Quote Originally Posted by newbie4life View Post
    "Everyone's an a** except for me and you... and I'm not so sure about you."


    2004 Larson 230LXI W/VP 5.0 AKA [COLOR=#00ff00]Mr Toads Wild Ride
    2003 Dodge ram 2500 W/5.9 Diesel-6spd manual

Similar Threads

  1. speed limiter or rev limiter
    By bspeednut in forum Mercruiser I/O & Inboard Engines & Outdrives
    Replies: 9
    Last Post: August 22nd, 2010, 11:07 PM
  2. questions about speed limiter
    By PowerAddict in forum Mercruiser I/O & Inboard Engines & Outdrives
    Replies: 1
    Last Post: May 17th, 2009, 08:34 PM
  3. Rev Limiter
    By Banzaib in forum Mercury & Mariner Outboards
    Replies: 1
    Last Post: February 15th, 2005, 12:48 AM
  4. rev limiter
    By Doug Durako in forum Mercruiser I/O & Inboard Engines & Outdrives
    Replies: 5
    Last Post: October 11th, 2003, 04:14 PM
  5. prop questions / rev limiter.
    By boaterntexas in forum Mercruiser I/O & Inboard Engines & Outdrives
    Replies: 10
    Last Post: July 11th, 2003, 06:02 AM
  1. iboats Forum Directory - Over 100,000 forum posts organized by topic