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Results 1 to 9 of 9
  1. #1

    Default 2000 Merc 40hp 2 stroke spark plug wire question

    Hello all......this engine is new to me....it came on a 24ft pontoon boat that I just purchased. I am tuning the motor up for Spring and came across this odd scenario. I was checking the plugs when I noticed the top plug wire was not connected to the uhhhhhhhh power pack side if that makes sense. The little boot has such a light grip it can easily slip off while say removing the cowling. Then I checked all 3 and they were all that way.
    So 2 questions.....
    Is this common for the small boots to have such a light grab on the power pack side? Not the spark plug side....the opposite

    When I looked at the end at the wire it was just that....an end of a wire....no metal clip or anything...so I guess the end of this wire when pluged on the power pack side is able to pick up enough energy and zip it along to the spark plug boot and ignite the plug.....?????? Seems to me there shold be some type of connector or at least some wire exposed......what do your Merc wire ends look like????

    Thanks!!!!

  2. #2
    Join Date
    Nov 2011
    Location
    tennessee
    Posts
    3,866

    Default Re: 2000 Merc 40hp 2 stroke spark plug wire question

    Someone has torn them out of CDM module...cut about 1/4" off end and rethread them

    Click image for larger version. 

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ID:	22760
    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

  3. #3

    Default Re: 2000 Merc 40hp 2 stroke spark plug wire question

    Wwwwwwhat......... Let me see if I understand what you are saying. So normally these plugs are screwed into the CDM? And in my case someone has ripped or tore them off the threaded portion of the boot??? So you are saying I can fix by cutting some of the boot off to be able to re thread right? I didnt realize the boot was threaded. Orrrrrrrrrr are u saying I need to do this to the end of the spark plug wire....ahhhhh that makes more sense. Ya the end of my wires have like nothing exposed I cant see how it even runs that way. I guess I could also buy new wires......should I ??? Or just fix? I noticed those wires are expensive. I would love to see a youtube vid on this repair....but I think I can figure it out

  4. #4

    Default Re: 2000 Merc 40hp 2 stroke spark plug wire question

    I have been watching videos to better understand what you were telling me.......I think I have it now.....wont know till I look at it tomorrow. Glad I accidentally caught this......those wires come off so easily I would have been dead in the water.....previous owner just had a bunch of work done to the engine before I bought it.....I have only sea trialed the boat so wouldnt have thought to check for threaded wires...........I did just rebuild the carbs....installed fuel filter....lower unit oil....and water pump kit......so following right behind previous owners work and making it my work.

  5. #5

    Default Re: 2000 Merc 40hp 2 stroke spark plug wire question

    Hey Bullet.....I realize talking to idiots probably drives u nuts but this idiot has a couple more questions if u will pop back on and steer me in the right direction I would appreciate it. Well u were exactly right....I removed the plug wires from the module and there is a screw in there. I trimmed back my wire 1/4 and tried to screw the wire down on this screw but it just wouldnt take.......any tricks to this simple task? Also it seems as if the end of the wires are left on purpose with what looks like conductive strans of fiberglass hair about 1/2"Click image for larger version. 

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ID:	22763 long. Could it be that the wire is just supposed to rest against the screw tip and conduct ....in addition to the hair stuff?
    I also noticed that my bottom module had a rusty screw inside for the wire to thread on....should I replace that module or just clean up that screw? Lastly .....my plugs which were very new to previous owner did not look right when I removed them.....they were almost white......what does that mean.....rich or lean? Is it possible my rusty screw module was causing this or should I check my oil injection system.....or typical bad gas?????
    Again I just bought the boat so this engine is new to me......on the sea trial it started pretty good....idled good.....ran at low speed good...then out of nowhere it seemed to pick up another cylinder.......I originally thought bad gas...but now after seeing wires not screwed in and one rusty screw in a module.....I am assuming cyl number 3 was intermittent.

    So if I only have you for this one last time....there u have it.......any direction would be appreciated.....see picsClick image for larger version. 

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  6. #6

    Default Re: 2000 Merc 40hp 2 stroke spark plug wire question

    Click image for larger version. 

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  7. #7
    Join Date
    Nov 2011
    Location
    tennessee
    Posts
    3,866

    Default Re: 2000 Merc 40hp 2 stroke spark plug wire question

    Those are suppressive wires and thiose are carbon strands. Take a razor blade and cut em off flush, use rubbing alcohol to lube the wire and screw it back into module. The rusty one you can insert some steel wool into area and use a small carpenter trim nail to move it around and remove the surface rust. The plugs look ok but but if engine has sat a while it would be advisable to inspect high speed jets in carbs.
    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

  8. #8

    Default Re: 2000 Merc 40hp 2 stroke spark plug wire question

    Thanks for coming back Bullet. Ok I will get those wires on those screws come hell or high water. I ordered another module off of ebay to replace or just as a back up for the rusty one....I already cleaned up the screw. I will check it for spark once I get it hooked back up again. Right now it is on a stand waiting for the boat to be done.

    Last question for you.....................How do I check to make sure my oil injection is working? I poured out all of the old oil and will start fresh....I did the same with the gas. But since the plugs are indicating lean I want to make double sure my oil is a pumpin.......I just cleaned and re gasketed the carbs and was sure to hook up oil linkage when I was done.

  9. #9

    Default Re: 2000 Merc 40hp 2 stroke spark plug wire question

    Boom done!!!! Dipped the wires in alcohol and wnet for it....got all 3 secured on the screw modules. Thanks for getting me to the finish line.

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