Jack plate

Richard Foisy

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Our dock is in about 18” of water and the boat drafts 12” so there is not much steering control with the outboard tilted at 45 degrees. I purchased a Powrtrans Magnum jackplate . It has an sealed electric actuator and allows 7 “ vertical lift which should help a lot in the shallow water. I was able to install it myself.
 

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Cool. Nice work.
 
I’ve thought about a jack plate, but that’s as far as it’s gotten.
 
There was talk of a jack plate long ago by a very intelligent member, if I remember correctly he said that in discussing it with Bennington that it would cause issues with warranty. Not sure what or how, just stating so other members are aware. It is cool looking from a personal view!
 
I remember that discussion also - though I was never considering one (especially with just a 50 hp).
 
Reviving the thread - off-season approaching so looking at some upgrades, JP being one of them.

Richard any issues so far? Thinking of a short setback (6”) Bob’s hydraulic. Got the same advice from Bennington engineer, they don’t recommend and a toon failure due to the JP would void the warranty.

My uneducated guess is that a short setback would not lever the transom as much, and careful use (i.e. raising only at low speeds) could keep the statistical odds of failure at the low end.
 
No issues so far . We bought a Magnum standard with a 4” setback. It is working great. Our soul purpose for the JP was shallow water ,especially docking. The Magnum raises 7” and now I have no trouble steering At the dock. I have tried it at moderate speed but it starts to have cavitation . In the photo its fully raised. The only thing I have to watch is tilting the motor as it will hit the tow bar when fully raised. Also when fully raised seems to impede the propulsion some in reverse. I think it’s because the prop water is hitting the back face of the center tube . Overall very happy with it.42E0E979-3537-439A-92CB-3F12AEA25B9D.jpeg353978F1-F515-4227-B0B2-CA372D0BBF1B.jpeg
 
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No issues so far . We bought a Magnum standard with a 4” setback. It is working great. Our soul purpose for the JP was shallow water ,especially docking. The Magnum raises 7” and now I have no trouble steering At the dock. I have tried it at moderate speed but it starts to have cavitation . In the photo its fully raised. The only thing I have to watch is tilting the motor as it will hit the tow bar when fully raised. Also when fully raised seems to impede the propulsion some in reverse. I think it’s because the prop water is hitting the back face of the center tube . Overall very happy with it.View attachment 28475
Great looking set up! I still wish Yamaha offered a white option for the lower HP motors, something about that color gives it more of a high-end, saltwater feel.

Appreciate the feedback!
 
It’s only paint ! . I added another image From below the water line,
 
I installed an Atlas jack plate after taking boat delivery from dealer. A few of my friends wished they would have looked at the Atlas jack plate before buying their Bob's jack plate. They think it is a built a bit heavier and it has a safety cable in case something on the plate breaks.

With a few LAN parts. I was able to interface the height sending unit on the Atlas to my Simrad screen so I didn't need install the jack plate gauge on my gaugeless dash. My jack plate height uses the black water tank field on my Simrad. The only issue is, it take a few seconds to update the screen because of the sampling rate on the Simrad. This was not possible with Bob's and Atlas said the same thing.

The width of the Atlas jack plate causes water to spray up on the deck of the boat between 3000 - 4000 RPM. Bob's is not as wide, but does cause some spray. I had spray guards made to stop the spray. See photo below This is on an 23 SSRXP and might not be an issue on a wider center toon.

My dealer drilled holes in my transom to use the top engine holes for the top set of bolts and for the bottom set of bolts they drilled the holes in the transom to use the 2nd set holes from the top because they said the transom was stronger there. Bob's jack plate predrilled bolt holes did not match what my dealer drilled. The Atlas jack plate has 3 sets height holes on the boat side so I was able to mount it without drilling more holes.
 

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Thanks for the pictures - out of curiosity where is the water splashing back, when it hits the rams?
Yes, where it hit the rams. One of my friends with the same toons and a Bobs jack plate, has some splash, but not as much I did.
 
Richard, nice work! Has running with the motor up shown any cooling issues? I know running in reverse with the motor pretty high will cause ours to heat up. Maybe the water there stays cold enough so cooling is not a problem? Summer surface temps easily get above 85 F here.
 
I haven’t had any heating issues. The Evinrude has water intake right at the point on the lower unit. Our water lake temp gets to 80F I don’t get any spray back either
 
Wouldn't the highest hole be the limiter as far as overhearing? Once the cooling system sucks air through the highest hole, I doubt much water gets sucked into any lower holes.

As far as the jack plate torquing on the transom, if the prop ventilates at higher throttle and high jack plate positions, isn't that self policing? There would not be much force (moment) on the transom while the prop sucks air. If that's what happens, I doubt you'll ever find yourself in a warranty situation.
 
I am not sure where the water intake is on other brands but on the Evinrude they are well below the anit ventilation plate . When I have the jack plate at the highest 7” position the anti-ventilation plate is just below the waterline. #10 on diagram.199613BF-ED5B-4FCC-A188-1631708200FB.png
 
On my prior pontoon and go fast boat with Mercury/Mercruiser motors, I had to tap and put ss plugs in the top 2 or 3 water intake holes to prevent the drives from sucking air. This is one of the reasons why I had water pressure gauges or have water pressure displayed on the Simrad.
So far on the Bennington, it cavitates before loosing water pressure. If I go to a different prop that allows me to raise the motor more, I might have to to tap and plug some water intake holes.
 
Here is a picture of the backside of my transom. Not sure even if we could move around the mounting holes if that’s possible given the additional cross bracing.

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