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  1. #1

    Default 40 Hp 2 Stroke 4 Cyl 2 Carb

    Ok were to start! lol
    Engine died replaced switch box and reg ran good. Died again no spark. Replaced stator and trigger. Ran but not great found a had a bad coil. Ran it again and jacking with the carb to no end. Finally it ran better than ever for a few hours.
    Part throttle it would surge like it wanted to take off.
    I feels like a timing problem to me or maybe a incorrect part. I cant read the serial number on the motor but I know it is around 94-96.
    Any ideas were to start?

  2. #2
    Join Date
    Mar 2019
    Ottawa Canada

    Default Re: 40 Hp 2 Stroke 4 Cyl 2 Carb

    Whats the compression?

  3. #3

    Default Re: 40 Hp 2 Stroke 4 Cyl 2 Carb

    Compression is 120 on all 4. I have doubts about the stator I installed (via CDI troubleshooting). The factory one was replaced with the switch box at the same time. The replacement stator died in a few weeks (no spark).
    I bought another stator (different P/N) and disconnected the new voltage reg/rectifier.
    I am not sure if I have the correct stator. I am confused on the bolt in magnets or glued in. The ring gear has magnets stuck to it but the ring gear is bolted to the "flywheel" that is bolted to the pickup for the trigger. I feel I am overlooking something stupid. Adding fuel via choke it falls in its face. For fun I will double check the floats. I also use the throttle cable as my idle adjustment. The set idle adjustment screw is over the max range.

    It feels like a timing issue to me.

  4. #4

    Default Re: 40 Hp 2 Stroke 4 Cyl 2 Carb

    I've got the same engine that is a 1996. I think you need to figure out exactly what configuration your engine is supposed to have because there were 3 different versions that I am aware of in relation to stators and associated electronics. There was a red stator (9AMP) and 2 different black stators (9AMP and 16AMP). Once you figure out what your engine is supposed to have, I would make sure that the parts you bought are correct.
    The other thing that you may want to do is verify that your timing is set correctly. Here's a link to a manual that someone posted that may be of help: http://forum.rentboat.dn.ua/manuals/merc/30_40.pdf

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