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Wiring battery isolator 3 pin

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  • Wiring battery isolator 3 pin

    Alternator supposed to connect directly to middle & 2 branches connect to + on each battery. Starter wiring branches off after the isolator so the starting current does not have to flow backwards thru isolator
    My problem where to find the alternator connection point for 70 amp alternator output . Engine is 1994 40TLRT Anyone have wiring diagram?

    My trim meter shows up at all times power is on - likely a bad potentiometer ?

  • #2
    lets start with the easy bit first, your trim gauge, the little sensor/arm on the motor is probably stuck, they jamm all the time, so as long as it is not broken off, just try to free it up and it will be OK, now for the battery switch, I have next to no idea what you are asking, things like alternator 70 amp output, flowback through isolator and so on, a battery switch is a pretty simple thing, one side of the battery positive goes to one side, the motor battery positive goes on the other, give us a bit more info so we can help you better.


    • #3
      More info

      I found the arm that drives the potentiometer for the trim . It responds indicating high trim when free but only moves down a hair when activated thru full range . Next move is to remove screw & try a clean up .

      As for alternator output & starter I have pictures of the starter solenoid arrangement ( i Think" ) So far I have found nothing connected is hot in run position Red is hot in run position(but not running) from battery ? Green goes hot when trim button is pushed. The rest I do not know Blue? Black

      To start with is this the solenoid providing current from battery to starter in start position ? Which wire goes hot ? Which wire feeds alternator output to battery
      I would rather not go back to a battery switch --isolator keeps both batteries charged automatically

      Now Also want to check timing box
      Picture shows three marks off indicator lever . What position is required for start with prime lever up dot ,I or II ?
      Symptom of problem hesitation on take off , loading up , finally cleans up & goes . Carbs have been cleaned several times !
      Attached Files