User Tag List

Thanks Thanks:  0
Likes Likes:  0
Results 1 to 12 of 12
  1. #1
    Join Date
    Nov 2004
    Location
    LEBANON OREGON
    Posts
    7,077
    Thanks (Given)
    1
    Thanks (Received)
    2
    Likes (Given)
    23
    Likes (Received)
    11
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    115 opti. Mid range miss. No codes from ECM

    Just as hull breaks over at approx 3500-4200 mid range miss. Goes away at wot. And flawlessly smooth to that point. Had a prior service place replace a coil. I've put 3 new on no change. And used my shop known good crank trigger. With no change. Could it just be the injector switching to it's high speed circuit in the ECM and being this thing has a jet there isn't the back pressure it needs to hold the fuel charge. Or. Should I look at the fuel system even though everything is see says it's electrical. Not fuel. Tops out at 5400 rpm just before limiter setting so it's not down any power. And runs consistently that rpm. So no power loss just a staccato at mid range as it comes up on plane


    no codes showing on CDS. Or my CDI scanners. Showed a missfire of all three cyl but. That has since been cleared and no repeat even with continue of problem

    4-16-2014. 25 years old today... the fishin boat doesnt look to bad for a classic does she


    things that were are no longer as they are today...

  2. #2
    Join Date
    Jun 2003
    Location
    St. Pete Fl
    Posts
    758
    Thanks (Given)
    0
    Thanks (Received)
    9
    Likes (Given)
    20
    Likes (Received)
    39
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    How old are the plugs and are they the correct ones?

  3. #3
    Join Date
    Dec 2002
    Location
    Ottawa, Canada
    Posts
    390
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    maybe a long shot and you say you have no codes, but look at the history codes if any and see what your neutral safety switch is saying at speed, I had one in the spring that had a faulty switch and it looked like it was popping into neutral at that mid range rpm, changed the switch and all was good.

  4. #4
    Join Date
    Mar 2008
    Location
    Tourist Trap, Florida
    Posts
    14,700
    Thanks (Given)
    380
    Thanks (Received)
    1280
    Likes (Given)
    5599
    Likes (Received)
    10930
    Mentioned
    2 Post(s)
    Tagged
    1 Thread(s)
    Maybe a double firing coil? Coil driver acting up? Any of the plugs worn more than the others?

    83 V-King, 96 Mariner, 200 hp ff block 2.5 w/a 28p choppa
    We gotta clean this liberal mess up, VOTE TRUMP TO MAGA!
    Rebuild thread:
    http://www.screamandfly.com/showthre...-it&highlight=
    http://www.screamandfly.com/showthre...cs.&highlight=
    Videos

  5. #5
    Join Date
    Aug 2009
    Location
    savannah,ga
    Posts
    704
    Thanks (Given)
    4
    Thanks (Received)
    7
    Likes (Given)
    12
    Likes (Received)
    41
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I worked on one of these a while back that someone put Autolite plugs in from the auto parts store. They were the correct cross reference per the book but the electrode length was different and the motor acted like it was dropping a cylinder at random. After getting the correct NGK Iridium plugs the motor ran smooth as silk. All of the Opti's are sensitive when it comes to sorry plugs and low battery voltage so those are the first places I start if they are running bad.

  6. #6
    Join Date
    Oct 2014
    Location
    Down under
    Posts
    7
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Also keep an eye on the 5Volt circuit in CDS as most sensors run 5v.

  7. #7
    Join Date
    Sep 2004
    Location
    lenoir city,tn
    Posts
    161
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    1
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    all the 115 optimaxs have a miss normally around 2500 t0 3000 rpms,

  8. #8
    Join Date
    Oct 2014
    Location
    Syracuse, IN
    Posts
    7
    Thanks (Given)
    0
    Thanks (Received)
    0
    Likes (Given)
    0
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    The Mid-Range miss you're experience is something that can be inherent with the 1.5L Opti. This sounds crazy, but take some long feeler gauges and make sure the throttle shutter is open .075" when "closed." I've seen it make a difference on some, but not all.

  9. #9
    Join Date
    Feb 2014
    Location
    Missouri
    Posts
    1,212
    Thanks (Given)
    2
    Thanks (Received)
    66
    Likes (Given)
    12
    Likes (Received)
    83
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    prop shudder. Or run lower octane if not 87
    Last edited by Motv18; 11-14-2014 at 10:26 PM.
    '06 Tracker All-Fish/Tournament V-18 90 Optimax, 46.8 gps Goal one complete reach 45 mph.

  10. #10
    Join Date
    Sep 2006
    Location
    Sweden
    Posts
    488
    Thanks (Given)
    14
    Thanks (Received)
    4
    Likes (Given)
    260
    Likes (Received)
    81
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I have an Optimax 90 (2012) with the same symptom, they are supposed to 'misfire' when accelerating - it is to do with the ECU going from low rpm to high rpm register.
    I also have an Optimax 200xs (2006) and that egine does not do this.
    RIB Unlimited 600/Merc 150 ProMax ss
    Allison SS-2000/Merc 200xs ss
    Hydrolift T-17/Merc 200xs ss

  11. #11
    Join Date
    Feb 2005
    Location
    seattle
    Posts
    2,654
    Thanks (Given)
    0
    Thanks (Received)
    17
    Likes (Given)
    0
    Likes (Received)
    33
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    my 2011 115 hp opti has no miss at any rpm.

  12. #12
    Join Date
    Feb 2014
    Location
    Missouri
    Posts
    1,212
    Thanks (Given)
    2
    Thanks (Received)
    66
    Likes (Given)
    12
    Likes (Received)
    83
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Another issue is the map balancing the load. If you hang plane. Ie dont step on the gas and get up you gain vaccume and the map leans the fuel back. Your not turning the enging enough rpm and the torque is gone then you lean miss/stall.

    Anytime you hang the rpm on a map driven fuel ststem you risk this condition.

    makes proping a b as well
    Last edited by Motv18; 01-10-2015 at 03:54 AM.

Posting Permissions

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