Won't get on plane... HELP

[tightline 700lx]

Ok here is what I got. I have a 2001 Nitro 700lx that I just put a brand new 115HP Optimax on. I am coming from a 2001 90HP ELPTO.



Took the boat out Friday to break the motor in with just me and it got on plane fine (full tank of gas), alittle slow but fine. Took the boat out on Saturday with the wife (140lbs) and 1.5yr old son and it was about the same as before (1/2 tank of gas). Caught some fish and had a livewell full of bream and it would not get on plane????? Had to make the wife sit on the front deck to get on plane...



Never had that problem with the 90HP.:unsure:



Here was my old set up: (90 ELPTO)

NO jackplate

13 3/8 x 21p Ballistic tip prop

hydrofoil

5650rpm @ 46-47mph (gps)



New set up: (115 Opti)

Manual CMC jackplate

13 3/8 x 21p Ballistic tip prop

NO hydrofoil

5350rpm @ 50mph (gps)



Which way do I need to move the jack plate and/or do I need a hydrofoil?

 

[joseph currier]

somthing sounds off your rpm's are low for that motor.

not sure what to tell you.

has tracker chimed in on the prop selection?

pretty sure the balistic is not there choice? also as far as engine hight goes

it's pretty simple the center of your prop shaft should be 3.5 inches below the bot of the hull with boat level and motor level.

there has been tons written about that very subject on this forum you can do a search and maybee find your spesicic condition?

 

[tightline 700lx]

somthing sounds off your rpm's are low for that motor.

Thats what I kinda thought but something wierd I've noticed is that all the older 115 mercurys (4cly) all run 23-25P props and all the newer 115 optimaxs (3cly) run 19-22p props. Any explanations there?

has tracker chimed in on the prop selection?

pretty sure the balistic is not there choice?

Tracker hasn't said anything but mercury's website said that I should be using a 19 or a 21p Laser II



and as far as the jackplate goes does moving the jackplate up or down help or hurt my holeshot???

 

[David Munaretto]

Your throttle probably isn't adjusted correctly - do you have a hotfoot? I was getting only 82% throttle out of mine after it was installed...

 

[joseph currier]

i was looking up rigging sheets i have and the 700 LX with a 115 opti

the motor should be at the hight that there is 3" betweem the top of the transom and

the top of the mounting bracket.

you should be running a 13.5 x 22 laser 2 part #92648.

my guess is it is a combnation of low engine hight and wrong prop.

the rigging for a 90hp call for the motor to be 1.5" lower and a 12.5x21 alu. prop.

as far as older 115 pushing bigger wheels that would be because the load dictated a bigger wheel.

115hp is 115hp the size prop is determind by the combo. of load and power the 115's you saw pushing a higher pitch prop were pushing a smaller load. or not cupped or raked the same.

 

[black crappie]

i had the same prob the boat would stand straight up with a full tank of gas and live well full. me and my fishen partner adjusted the jack plate did not work.Check out the prop and it was right bought a sting ray and never looked back.Hydrofoil is worth the money i thought.Worked good on my boat i hope that helps

 

[Scott Hammer TOXIC]

As has been said many times, a foil is a band-aid fix for a bad setup and has some definite concerns. There is a time and place for them but fixing a setup problem is not one of them. Explore your prop/jackplate/weight distribution first.



TOXIC

 

[tightline 700lx]

All great ideas. Thanks for the advice.

Your throttle probably isn't adjusted correctly - do you have a hotfoot? I was getting only 82% throttle out of mine after it was installed...

No hotfoot... How can I find out if am getting only partial throttle out of my rig cause thats kinda what it felt like to me... Even when I was getting on plane it wouldnt happen until the throttle was all the way down.

was looking up rigging sheets i have and the 700 LX with a 115 opti

the motor should be at the hight that there is 3" betweem the top of the transom and

the top of the mounting bracket.

you should be running a 13.5 x 22 laser 2 part #92648.

Thanks for looking that up for me I will doublecheck that this afternoon...



Sometimes I wonder it Triton, Blazer, etc. have a site like this one dedicated to their boats cause this one kicks a$$... Just Sayin

 

[Dan J.]

A 21P Trophy Plus (four bladed prop) with two plugs out and two mediums in will put you in a sweet spot you'll find hard to beat on that hull and motor combo.

 

[black crappie]

I have a 150 merc with 24pitch what kind of rpms should i be running maybe that foil was a band aid i just could not figure it out?

 

[TOMMY RICH]

We had a prop guru here for years that always said that a foil was always a band-aid covering up a problem.

 

[joseph currier]

black crappie

your question is generic in nature .

you would do better giving all the specifics like motor model,boat model and years,your speed at wide open throttle, your rpms at same, your engine hieght ( prop shaft in relation to the bottoim of your hull while both are level ) current prop, pitch, dia ,material.

then and only then would any of us be able to evaluate your rigs proformance.

i would agree a foil on anything bigger than a fourty horse is silly and dangerous

if it improves your proformance the something is wrong on the setup.

if you have ever seen someone catch the cornner of a foil in i tight turn you would understand, the boat goes into an uncontrolled spin.