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motor height question

Discussion in 'Boats and Motors' started by bassteaser1, Feb 13, 2005.

  1. bassteaser1

    bassteaser1 Feared by all that swim

    I just got a 40 hp tiller motor for my Sylvan backtroller and it was an unusual 22" shaft motor.It seems a little long for the boat.I measured my transom and it was 20".Will this cause a problem?Should I put a 2" spacer in it or don't worry about it?
  2. Your cavatation plate should be even with or slightly below the bottom of your transom.

  3. UFM82

    UFM82 The one others want to be

    Should be ABOVE the keel- you don't want it dragging in the water when you are running. The anti-cav plate should be an inch or so ABOVE the keel so that when you are running down the lake, the water comes up off the keel and hits the bottom of the plate. This keeps the water down on the prop and gives the rear of the boat lift as well. If it is underwater when you are running, as it will be if it is even with or below the keel, it will dig in to the water and pull the stern down if you have negative trim and it will plow through the water and cause all kinds of drag with positive trim. That plate should ideally be above the water when you are running.

    If the plate is anything lower than even with the bottom of the keel, it needs to be raised.