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  1. #1

    Join Date
    Sep 2013
    Location
    Bayou Vista, TX
    Posts
    20

    Bad DESS post or MPEM?

    Hey guys. I posted this on another forum and haven't gotten a response so I thought I would try here..

    Went to ride the ski a couple days ago (97 SPX 787) and as usual, I let it run for a few seconds before I shove it off my jet dock. It started as it always does but then after a few seconds, I noticed it started to idle down quickly. Then it just quit. I tried to restart and it wouldn't fire. I get two beeps when I put on the key and it will crank and crank but no start.


    I charged the battery last night, threw it in today, still no start.


    I tested the DESS post per the shop manual and I think I did It correctly. I got good readings with the exception the black/black&yellow post test. I could not get a reading when I tested those two together and the post unplugged as I thought I understood in the manual. Could this be a bad DESS post or is it still a possible bad MPEM? The rectifier is new, all fuses are good, and I recently installed a new buzzer. Obviously the battery is good as well. I unplugged and replugged all connectors in the ski thinking that maybe I just had a bad connection somewhere. Still nothing.


    Any insight or help would be greatly appreciated.


  2. #2

    Join Date
    Mar 2006
    Posts
    1,833
    +1
    119
    fuel selector switch in the correct location? Is there gas in the tank? sediment bowl sealed to the cap? Sounds like a fueling issue to me.

  3. #3

    Join Date
    Sep 2013
    Location
    Bayou Vista, TX
    Posts
    20
    Fuel switch is on but I didn't notice anything incorrect about the fuel bowl when I was in there testing the post I didn't really study it though. It's worth mentioning that when i replaced the fuel lines i did clean out the fuel bowl and filter. I did notice a fairly strong fuel odor when I opened the hood and lifted out the dry box. Not that it matters but it did seem to run flawlessly a few days before. Clocked it at 59mph via GPS. I guess a double check is in order.

    Now that I'm thinking about it, maybe it is a fuel supply issue... When I would load it onto the trailer, it always liked to die on me as I would try to drive it up the bunks. Now that I'm using a jet dock, it has died on me twice while driving it up that. When it's sitting on the jet dock, it does sit at a slight angle, nose high.. Also, it is lower on fuel than it has ever been since my ownership sitting at around a 1/4 tank (I usually keep it over half tank). I'm wondering if I fill it up if that will narrow down the problem.

  4. #4

    Join Date
    Aug 2008
    Location
    Eastern NC
    Posts
    223
    +1
    8
    See if you are getting spark. That should help you sort out fuel vs electrical

  5. #5

    Join Date
    Sep 2013
    Location
    Bayou Vista, TX
    Posts
    20
    Well, Jim hit the nail on the head. It's definitely a fuel issue. I out about 2gal of fuel in and she fired right up. Even sitting nose high on the dock I could see a little fuel through the front of the tank. I'm not sure why it wasn't getting any though. Do the fuel senders tend to go bad and not read correctly?

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