Jack Plates for 1990 Grady 28 Marlin

[Heff]

Hi Everyone! This is my first post, on
my first Grady. I bought a 1990 Grady 28 Marlin which had been re-powered with 2016 Mercury Verado 250’s. I had a feeling the motors are mounted too low and I need to come up at least two holes. The motors only have one more hole up I can go. Does anyone have any recommendations on a specific manufacturer of jack plate that works well on a 28 Marlin? I am just learning about jack plates, but from what I’m gathering, since the motors are essentially mounted on a bracket when it comes to the 28 Marlin, I would think a minimal setback would be desired? Also, I think I would opt for a manual jack plate vs. hydraulic, less things that can fail.
any insight/recommendations are greatly appreciated!

 

[Chessie246G]

Manual would be my suggestion. Hydraulic have their place but mostly used on shallow water boats... flats boats or bass boats. Since you are just trying to raise the motor slightly and leave it there, manual would be the way to go.

 

[Doc Stressor]

I put a 4" manual jack plate on my 226 when I re-powered with a Honda 250. I am very happy with the modification. I increased my fuel efficiency by at least 10% by tweaking the engine height. Hydraulic is of little use on an offshore boat. I got mine from Bob's Machine shop. They are very knowledgeable and even modified the shape of the mount to clear the bang plate on the 226 transom. Unfortunately, they no longer make the cheaper manual jack plate I have. They now use the same frame as the hydraulic version and just replaced the ram with the manual screw adjustment. This works fine but now costs $950 for the 4" setback unit.

Be advised that if you try to adjust the engine height with the screw, be aware that you must support most of the weight of the engine either with a jack under the lower unit skeg or by placing a wood block under the skeg and raising the front of the boat on a trailer.

https://bobsmachine.com/home/

 

[Chuck_NJ]

CMC Static Jack Plate 5 inch vertical extension | T-H Marine Supplies - Default Title - T-H Marine Supplies

CMC Static Jack Plates – 5” Vertical Extension The 5 INCH VERTICAL EXTENSION allows the motor to be mounted 5 inches higher than the standard mounting height on the transom. It is a must for conversion from prop to jet drive. Anothe

thmarinesupplies.com

 

[Doc Stressor]

Chuck, those pieces are for extending a pre-existing jack plate. Like if you are going from a prop to a jet outboard.

When you shop, remember to check the weight and hp limits of each unit. Not all manual jack plates will hold a 250 hp motor.

 

[Chuck_NJ]

Chuck, those pieces are for extending a pre-existing jack plate. Like if you are going from a prop to a jet outboard.

When you shop, remember to check the weight and hp limits of each unit. Not all manual jack plates will hold a 250 hp motor.

Interesting since I used on my 87 offshore with bracket to use a 30” shaft zero additional setback and I called the company and they said I was good to go. I have no issues and you can modify it to get the height you need.

 

[Doc Stressor]

You can use it on any transom to raise the engine. But it is a fixed extension, not an adjustable jack plate that the OP is asking about.