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Thread: Twin 150s issue

  1. #1

    Default Twin 150s issue

    hello I have twin 150s mercury. 2011

    we just installed it back on the boat as I bought it used
    now the problem I have is when driving with the waves or forwarding waves the motors seems to be forcing it self when I give it gas and the revs seem to go up and down by itself like something keep it back. Iis sounds like example if u was to tilt ur motors way up and then give it throttle u know that sounds it make as u know the motors are tilt up to much. I thought maybe at first it could strong current it canít be. As I fish all day all over the place and it only happens when driving with the waves. If I go into the waves it runs perfect. In calm water it rides perfect. The waves was a lil ruff though
    i tried all ways with the trim taps and tilt. But nothing made a difference
    could it be something with wrong props? Something set up with the motors on boat? Or something with engines itself?

  2. #2
    Join Date
    Apr 2016
    Location
    barnegat NJ
    Posts
    3,129

    Default Re: Twin 150s issue

    Are the anti-ventilation plates level with the very bottom of hull? Is your engine reaching WOT,if not your not propped perfectly

  3. #3

    Default Re: Twin 150s issue

    well not sure what is ventilation plates what is that?

    well in calm flat water it drives full throttle straight and no issues or nothing at all. runs prefect , it is only doing this all the time when riding in forwarding seas, it does it sometimes in heading seas where it revs up high but not much.
    i was wondering if maybe wrong props or pitch is on or maybe the motors need to be lowered or something else is wrong?

  4. #4
    Join Date
    Apr 2016
    Location
    barnegat NJ
    Posts
    3,129

    Default Re: Twin 150s issue

    Anti-ventilation plate is the horizontal fin above the prop,needs to be level with the lowest point of hull

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