Jack Plate help for an AL Bass Boat

[mad hatter]

Hey guys, please help me out!

I need advice on adding a jack plate to a G3 Eagle 175 with a 90 HP Yammy. I want to add either a 4 or 6" set back but I'm worried about the structural effects. Can anyone help me understand what the load increases might be?

Low water is chewing up my props. The engine cav plate sits 1/2" below the hull now. Adding a Hyd. JP should get my motor up during slow speed and improve performance at speed.

Any advice on this would be appreciated.

 

[Bob_VT]

Re: Jack Plate help for an AL Bass Boat

you should go with the smallest you can fit.....so it does not have any ill effect on your steering and controls.

 

[mad hatter]

Re: Jack Plate help for an AL Bass Boat

Thanks Bob_VT

I plan to change those out too. I'll be going for something like a Sea Star and Hot Foot anyway so no worries about controls.

I'm more concerned about the transom structure. I'm told that to get clean water, I need to move pretty far away from the hull. I'm sure there's a diminishing return on a boat this size, but I wonder where the sweet spot is.

 

[Bob_VT]

Re: Jack Plate help for an AL Bass Boat

I would shoot dhadley (hangs out in the prop section of the board) a message .....he is the best prop person I know and you said the magic words...... "diminishing return" All the money you spend may not yield but 1-3 mph.

I used a hotfoot on my old ranger with a 150 and a mechanical jack plate. I even have my T&T controls wheel mounted..... I did not dare let go in rough water at WOT and I felt more secure.

 

[moonfish]

Re: Jack Plate help for an AL Bass Boat

Do you have flotation pods? I just bought a used boat and it's the same way, mounted a little low, the back end really sits low. I wish the motor was higher but I don't know what $ it is really worth to gain an inch? I've read really good things about the pods though, pulling the back end up maybe a couple of inches.

 

[Bob_VT]

Re: Jack Plate help for an AL Bass Boat

When it comes right down to it.... you could rebuild your transom an inch higher for less cash too!

 

[mad hatter]

Re: Jack Plate help for an AL Bass Boat

Didn't know what pods were so I did some reading on one of the other forums. Nope I don't have those but that's in interesting idea though. I'm not sure I want to do that kind of surgery to my boat. It's practically new and I'm not really sitting that low in the hinder end. I am running in very low water with a seven year drought going on where I fish and I thought adding a JP would be a simple fix. I'm not interested in hurting my boat any as a result and if a jack plate is going to double or triple the loads into the transom, I'll live without it.

 

[Frank Acampora]

Re: Jack Plate help for an AL Bass Boat

A jack plate will not add appreciable loads on the transom. You still will only be delivering 90 HP to the transom. And since the stationary part of the jackplate will most likely be at the same height as the engine clamps were, there will not be an increase in twisting force on the top of the transom.

What it will do is set the engine back six inches and give a longer lever arm to the thrust. The engine weight is shifted back and the thrust will raise the bow some. Also, with the six inch setback, imagine the water coming off the transom. Because of the angle of the boat, it rises. SO: with the setback and the boat at normal plane, the engine needs to be run a bit higher to get the anti-vent plate even with the water. Depending upon hull, a couple of inches or more above the bottom.

 

[Willyclay]

Re: Jack Plate help for an AL Bass Boat

Here's a link to a thread about floatation pods:

http://forums.iboats.com/showthread.php?t=347941

 

[mad hatter]

Re: Jack Plate help for an AL Bass Boat

All, you've been very helpful and I appreciate the responses. I'm going to consider flotation pods but for now, I'm going to see if I just raise the motor up one hole, I'll improve things a bit and no cash spent. I still may pop for the jack plate but I'll keep it to 4".

Thanks

Mad