Using a Manual jack plate to fit a 25” shaft motor

[Trademacher]

I realize this application is contrary to popular opinion. I don’t need people saying don’t do it. I understand it’s not common practice. Just humor me. Will a 10” set back jack plate with 5” of lift maxed out allow enough lift to make this set up work. Seems like it would work fine. Why or why not.

 

[Scott Danforth]

Rule of thumb is you can rais 1" for every 4" of set back. So with 10" of set back, that is only 2.5" and not 5"

 

[Trademacher]

Rule of thumb is you can rais 1" for every 4" of set back. So with 10" of set back, that is only 2.5" and not 5"

Okay so if we are talking a 20” motor this is the case? If it’s 25” you could mess with this standard with the lift from the jack plate? Or am I missing something?

 

[JimS123]

You are trying to put the wrong length motor on your boat. So, you need to raise it 5".

When you set back a motor, it has to be raised just because of the setback. So, for 10", you need to raise it 2.5". That's in addition to the 5" you already need to raise it. So, you need to go up 7.5".

Hope my explanation is clear.

 

[roscoe]

What Jim said.

Can be done if you can mount the jack plate higher, or high enough.
Or, if you have room to drill more holes.

 

[Texasmark]

I realize this application is contrary to popular opinion. I don’t need people saying don’t do it. I understand it’s not common practice. Just humor me. Will a 10” set back jack plate with 5” of lift maxed out allow enough lift to make this set up work. Seems like it would work fine. Why or why not.

Recalling the "big guns" on here years ago said 1" rise for 6# of setback so 10", about 1 1/2 inch inherent in the setback so you could/should put her on and set it at 3 1/2 inches up for starters and then adjust as necessary. How you boat will come to play in that....the faster you run your rig the higher it will be and running at just on planing speed, pulling water toys, or in big water, the lower it will be. A SS prop with blad tip cupping may be in order to prevent/reduce any "ventilation" tendencies.

Thats what I'd do knowing what I know about your rig.....essentially nothing. Grin