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  1. #1

    Join Date
    Jan 2010
    Location
    Midland, ON
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    03 msx 140 not reaching full rpm??

    Hi ALL,
    New to forum and want to say that this forum is awsome. I have recently purchased a salty 03, MSX140 with 95 hours on it. The previous owner purchased a new impeller that came in the bos with the ski and said it needed to be changed?? I pulled the pump with K447's awsome Utube segments, only to find out the pump and ring were perfect. Turns out it was the front drive shaft support bearing that was baked. I rebuilt the bearing assembly and put back pump and ride plate for my first test ride..... only to find out that i cant reach past 4800-4900 rpm???? There is no warning light that comes on, nor any codes flashing? I'm running last seasons fuel. All three cylinders are 120 psi. No apparent fuel leaks in the hull, and the reverse is all the way in the down position. I took off the TPS and it looks good, however i have not done a ohms check.

    The old owner cut the speedo wheel wire when he took off the ride plate. Does it matter that the speedo registers "0"??? Does it need some kind of speed sensor in the MFD??? I have read previous post's and the suggestion is fuel pressure related??? Not sure where to begin. The Ficht looks pretty over whelming. I work as a mechanic at a marina however these little ski's are like swiss watches with many precise parts, and thats new to a meat and potato kinda guy.

    Thanks,
    C.


  2. #2
    Click avatar for tech links/info, donation request K447's Avatar
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    Welcome

    Sorry to have missed your post earlier. Been rather busy these days...

    The speedometer display is just for your amusement, the Ficht EMM doesn't see that signal.

    Are you running the correct spark plugs?
    NGK PZFR6H only.

    Fuel pressure is checked at the schrader valve tee. Should be over 20PSI as soon as the engine cranks or starts.

    Does the engine run smoothly at the WOT RPM level?

    The only reliable test for a TPS is to install a new or known good TPS.

    BTW, how did you get the drive shaft out to work on the through-hull bearing carrier?

  3. #3

    Join Date
    Jun 2009
    Location
    McAlester, OK
    Posts
    11
    I had a 2003 with only ~30 hrs on it and the middle cylinder wasn't firing. The only way I knew that was that a new plug was clean. K447 helped me as much as he could help a rookie. Good compression, good fuel press, look like spark at the plugs, I had two skis so I robbed the EMM from the other and same problem. I took it to a mechanic. After 5 weeks and going through "everything", the coil that fires two cylinders had a short across to the engine. I forget how he found it. He didn't have the right tools and happened to find it. He replaced the coil and it runs good. Chances are that this is not your problem, but could be.

  4. #4

    Join Date
    Jan 2010
    Location
    Midland, ON
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    4
    Sorry for not getting back sooner But this is whta i have found out. A) Yes the fuel pump regulator was at bottom of pump!!!! Fixed that as per excellent intstructions K447 and Green Hulk. Now have 25 psi at schrader. Went out for a rip and noticed mag side coil has very weak spark. Only running on PTO and middle cylinders? Checked that the orange wire going on top of coil has low voltage?? Traced wire back to emm with no shorts and seems to go into emm where the problem is?? Can i swap out coils to see if that is problem??? I think coil is ok. Any ideas??

    Thanks
    C.

  5. #5
    Click avatar for tech links/info, donation request K447's Avatar
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    You can swap coils to test. Just swap primary and secondary wires together between the coils. The single and double pack coils are electrically the same, just two coils in a single package.

    Ohm test all the coils first. They should all measure very similar resistances to the ground tabs. Coil primaries are very hard to measure with accuracy, as the resistance values are a fraction of an ohm.

    You might also try removing and cleaning the grounding of the coils, to make sure there is no paint or corrosion affecting the coil grounds.

  6. #6

    Join Date
    Jan 2010
    Location
    Midland, ON
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    Have checked coils and are fine. After extensive checking it is determined that the orange/blue secondary wire from emm to the single mag side coil is not sending voltag to the coil. I will search posts for the place i think is in California that checks/services them. Just wondering if i should look for a used one and get injectors calibrated???? Not sure best way to go since the ski is for sale?

    Thanks,
    C.

  7. #7
    Click avatar for tech links/info, donation request K447's Avatar
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    Quote Originally Posted by REG-DOG View Post
    ...determined that the orange/blue secondary wire from emm to the single mag side coil is not sending voltag to the coil.

    I will search posts for the place ... that checks/services them.

    Just wondering if i should look for a used one and get injectors calibrated???? Not sure best way to go since the ski is for sale?

    Thanks,
    C.
    EMM repair will be around $700, if it is repairable.

    Company is DFI Technologies in Alabama.

    If you buy another used EMM, my recommendation is to only purchase one from another MSX 140.

    Do you have a local dealer that can transfer the injector data between EMM?

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