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Good question. I don't know enough about the use of jackplates toSaltyDawg asked: Do you think these boats require jack plates and/or trim tabs to preform well under normal circumstances
comment, yet. Do they let you run shallower? Do they make you run
faster? Do they improve handling, holeshot? Does the extra load and
weight being pushed back behind the transom affect draft?
How should a motor be set up on one? Procedure for adjusting?
Hydraulic, electric or manual? I'm going to be digging all over the
web pulling up websites and reading all I can find. Those of you that
run them on your boat...your comments would be appreciated.
What I find I'll post.
One use that requires a jack plate is the installation of a jet outboard.
It's the only way to fine tune the height of the leading edge of the
intake to where it won't ventilate. You have to be able to adjust to the
last 1/8th of an inch to get the pump to run it's best, without throwing
spray back over the top of the transom and filling your hull.
For a small jet outboard a minimal setback manual jack plate is all
that's needed. Once set, no further adjustment is necessary.
I have a problem with that statement. After all the research I've doneOnce the water under the boat passes the trailing edge of the
transom, it angles upward. So even when the prop is higher than the
bottom of the boat, it sits far enough back to work in solid water.
on pocket tunnels, the amount of rise of the water off the bottom of
the transom at planing speeds, is not that much. I call BS on that quote.
No BS here, just basic set up info:
Because a standard template is used to drill the bolt hole patternNOTE: There are several models that are longer than the actual advertised dimension, they are:
* Mercury/Mariner 6 - 15 and Sea Pro: 15 inch is 17 3/4 inches, 20 inch is 23 1/4 inches.
* Mercury/Mariner 20 - 25 and Sea Pro: 15 inch is 17 inches, 20 inch is 22 inches.
* Mercury/Mariner 40, Mercury Classic 20: 15 inch is 16 3/4 inches.
* Mercury/Mariner 75 through 125: 20 inch (L) is 21 11/16 inches, 22 1/2 (LL) is 24 1/6 inches, 25 inch (XL) is 26 11/16 inches.
through the transom, a jack plate would allow correcting the height
of the engine installation to the true shaft lengths.
The basics of jack plates as read are these:
Used to adjust the height of the motor to it's highest running position.
The smaller the amount of your lower unit in the water, the less friction/drag is produced.
Less drag means better speed and fuel economy.
Moving the prop further back from the transom allows time for air bubbles to rise up.
That means cleaner water for the prop to bite into.
At idle speeds the prop and skeg are higher up than on a standard transom mount, run shallower at idle speeds.
Does add weight to the transom, which means slightly more draft.
Increases static rotational torque to the transom, if you don't have a strong hull, don't use a jack plate.
The maximum height of lift is limited by the location of the water intake and the type of propeller.
Conclusion: If you're looking for the absolute best performance from your outboard, get a jackplate.
If you just want to go fishing, they're not necessary.
Trim tabs: Any hull large enough to run open water safely,
will benefit from the use of remotely adjustable trim tabs.
Trim tabs allow you to adjust the way the hull runs, fore to aft,
port to starboard, to fit sea conditions and vessel load, while under way.
A very nice setup: