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Zorakk

Jackplate opinions

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Hi all. I am pondering installing a jackplate on my boat. I am not looking for any performance gains but am considering it as I'm afraid my lower unit will block one side of my sidescan transducer. I have a number of variables to add to the equation. I currently have  4" and a 6" manual jackplates . I also have another identical sidescwn transducer, but would have to buy a splitter cable and put a few more small holes in my transom . My transom seems to be solid but with my old mercury 80hp I might have to get creative on the install due to the external hydraulic trim cylinders and the fact that my mmotor might sit too high at the minimum height setting using the plate. Just looking for some thoughts or ideas. 

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It’ll be a lot of work, but definitely worth having a jack plate. You gotta make sure your current hoses, cables, and wires aren’t gonna come up short when you move the motor back, though. As far as your transducer and transom holes, if you’re gonna do all the work to install a jack plate, I’d take the few extra minutes to fabricate a way to mount the transducer onto the jack plate. You shouldn’t be too high, but I’d measure how far below pad your prop shaft is now, then measure how far up the jack plate is gonna be at its lowest position, and that should give you a rough idea. Generally, you’ll get better performance with the engine higher, and farther back. 

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I gotcha. I do know my anti ventilation plate is 2 " above the bottom of the hull with the water pump intake top hole even with the bottom of the hull. I have a drawing ( that i left at work) that shows all the dimensions i pulled. Perfofmance wise, the boat comes right up on plane and max speed is 37 mph with the wife and fishing gear on board. I think my motor will be too high with a plate set at the lowest position. I will be pulling the motor anyway so I will temporarily bolt up the plate motor combo to see how everything looks. I am also installing a water pressure gauge as well. I will post a pic tommorrow with dimensions.

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Actually, that sounds like it’ll be fine to me, just kinda picturing it in my head. As you move an engine back, it can go higher without losing water pressure. I can’t remember the rule of thumb on it, so many inches back is one inch up or whatever, but if your top hole is even with the pad now, even if it goes up a bit, you should be able to get plenty of water I would think. Most guys, without low water intakes, can still generally run with the prop shaft a couple inches below pad, which seems about right from what you’re describing. 

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I think i might give it a shot depending how everything measures when i mock it up. I think I have read that the rule is 1" higher for every foot setback, but my knowledge about jack plates is based on what I have read, not on experience. Here is a pic of my current dimensions

BOAT INFO2.pdf

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