Can the set back on a jack plate screw your boat up?

[salmonite]

i purchased a 98 crestliner with a jack plate mounting my 115hp johnson to it. My question is that my boat sits so low in the back that the water comes in my drain holes in the spill way when floating in water.

My question is "could extending my motor almost 8-10 further back off of my transom pull my boat further into the water"

boats transom is rated to 150hp so the motor is not heavy and not waterlogged.

this is my jack plate
http://www.cabelas.com/cabelas/en/t...cm_pla=Primary&cm_ite=cabela&_requestid=41588

Also i don't think i need it for the purposes people usually put jack plates on. looks like my prop still would be mounted correctly if put directly on transom

 

[salmonite]

Re: Can the set back on a jack plate screw your boat up?

bump to first page

 

[Bob_VT]

Re: Can the set back on a jack plate screw your boat up?

You are not going to gain anything.....except a lighter wallet.

Are your control cables long enough? What about your steering cable?

It will put your transom even lower since you are going to move the 300 lbs further out.

 

[bob johnson]

Re: Can the set back on a jack plate screw your boat up?

You are not going to gain anything.....except a lighter wallet.

Are your control cables long enough? What about your steering cable?

It will put your transom even lower since you are going to move the 300 lbs further out.

he already has the jack plate, he said it came with the boat!!!

and yes, the motor would have more leverage to weigh the stern down!!!!

you are essentially hanging the weight further off the back but not adding any bouying surface area under....as you would by making your boat longer...more weight but subsequent support!!

I added a jack plate on my boat but went and added flotation pods on the back as well....to help float the rear weight...


bob

 

[salmonite]

Re: Can the set back on a jack plate screw your boat up?

yeah i gotta get rid of it i think.... maybe i will have a heavier wallet when i sell it.

 

[bob johnson]

Re: Can the set back on a jack plate screw your boat up?

yeah i gotta get rid of it i think.... maybe i will have a heavier wallet when i sell it.

yeah a fixed jackplate that only gives you negatives......time to go!

a hydraulic jack plate on the other hand might be worth the drawbacks....especially if you boat shallow..

the jack plate should have let you mount the motor higher than normal....

about 1-2" higher than the bottom of the hull!!

if you didnt take advantage of that...then the jack plate is only hurting you..

dont know why you boat is sooooo heavy...

also think you might have a prop that is slipping some...

or your tach is wrong

good luck

bob

 

[salmonite]

Re: Can the set back on a jack plate screw your boat up?

bob,
did you look at my other posts about my prop?

so obviously i had some issues with this boat and she filled full of h20 two weekends ago and i am just trying to figure out why?

And before anybody asks YES, for the hundreth time, my plug was in!

I believe it had to do with how low my boats sits and my deck plate came loose and then water was just pouring in a 8 inch hole in my boat

 

[salmonite]

Re: Can the set back on a jack plate screw your boat up?

the jack plate should have let you mount the motor higher than normal....

about 1-2" higher than the bottom of the hull!!

if you didnt take advantage of that...then the jack plate is only hurting you..

also maybe i am missing something. Right now my cavitation plate is equal with my bottom of my boat. I was under the impression this was optimal????? Are you saying i could move it even higher with the jack plate on???

 

[bob johnson]

Re: Can the set back on a jack plate screw your boat up?

also maybe i am missing something. Right now my cavitation plate is equal with my bottom of my boat. I was under the impression this was optimal????? Are you saying i could move it even higher with the jack plate on???

yes that is why people use manual jackplates...they want SETBACK, so they can mount their motors higher..they can dial it in with the manual adjustments...and leave it...the water rises up as it leaves the transom...the further away from the back of the boat the higher the water is....jack take advantage of this and put less motor in the water..thus less resistance and more speed...but it might mean little to a guy who could care less if the boat goes 38 mph or 40 mph.... to some guys it matters and it is just one stab at getting more speed one little bite at a time..

for you...with your weight issues( I really think you must have water logged flotation under the deck)

id just do away with the jack and mount to your transom at level or an inch above...you should have at least 4 sets of holes to choose from.

right now you dont need cantilevering forces working against you, till you figure your weight issue

or your distribution of weight issues.

you got a rear mounted gas tank? rear mounted batteries?

you wouldnt have a rear half live well would you??

if you really are that heavy trim tabs may help you a lot!!!

as for the deck plate...you got to solve those issues and keep water out of the boat..

a lot of great lakes walley fishermen have a seperate plate for the splashwell to block waves coming over their low transoms.

i got one!! because i back up in heavy seas often...and that cuts hundreds of gallons per day ...some days

bob

 

[Willyclay]

Re: Can the set back on a jack plate screw your boat up?

I added a jack plate on my boat but went and added flotation pods on the back as well....to help float the rear weight...bob

Any pix so the rest of us can learn?

 

[salmonite]

Re: Can the set back on a jack plate screw your boat up?

Bob,
I am going on the weight of the boat from my coast guard panel. I have never weighed the boat myself. If i did get it weighed do you know what a trailer for a 18.5 boat and a johnson 115 would weigh so i could subtract it.

also both batteries are in the back and gas tank is in the middle.

 

[bob johnson]

Re: Can the set back on a jack plate screw your boat up?

Bob,
I am going on the weight of the boat from my coast guard panel. I have never weighed the boat myself. If i did get it weighed do you know what a trailer for a 18.5 boat and a johnson 115 would weigh so i could subtract it.

also both batteries are in the back and gas tank is in the middle.

the Johnson ouitboard probably weigh right about 315 lbs.. but since its a fitch (I think I read that somewere) it might be a little more or less, you could go to the trailer makers web site and come up with the trailers weight...2 axels or one??? anyway id be suprised if it weighs more than 700 lbs.


bob

 

[bob johnson]

Re: Can the set back on a jack plate screw your boat up?

Any pix so the rest of us can learn?

this pix was originally to show the kicker bracket i made, but it shows the jack plate and pods pretty good

the last is after i welded the pods on , I had to reinstall the plastic composite transom support.

bob

 

[Willyclay]

Re: Can the set back on a jack plate screw your boat up?

Thanks, very nice!