Boat Falling Off Plane

[RyanTurn91]

Hi, coming out of a 1998 Fundeck with a 502 and a Volvo Penta dual prop drive, I bought a newer 28' Deckboat with a Merc 600 and a XR drive with a 5 blade on it, my question is anything below about 35MPH the boat wants to fall off plane, is this normal and to be expected with a higher performance boat? My Fundeck was easy to drive and once on plane was easy to keep on plane at lower speeds. The reason I'm bringing this up is i understand I bought a higher performance deck boat meant to go faster but i didn't realize i would be giving up the "boatability" at lower speeds, sometimes i like to just cruise with the family including 2 babies around 2 yrs. old. thoughts?

 

[JFMFG]

Hi, coming out of a 1998 Fundeck with a 502 and a Volvo Penta dual prop drive, I bought a newer 28' Deckboat with a Merc 600 and a XR drive with a 5 blade on it, my question is anything below about 35MPH the boat wants to fall off plane, is this normal and to be expected with a higher performance boat? My Fundeck was easy to drive and once on plane was easy to keep on plane at lower speeds. The reason I'm bringing this up is i understand I bought a higher performance deck boat meant to go faster but i didn't realize i would be giving up the "boatability" at lower speeds, sometimes i like to just cruise with the family including 2 babies around 2 yrs. old. thoughts?

30mph is about right. My 29 Nordic doesn’t roll over till about 25-30

 

[BigAl96]

Hi, coming out of a 1998 Fundeck with a 502 and a Volvo Penta dual prop drive, I bought a newer 28' Deckboat with a Merc 600 and a XR drive with a 5 blade on it, my question is anything below about 35MPH the boat wants to fall off plane, is this normal and to be expected with a higher performance boat? My Fundeck was easy to drive and once on plane was easy to keep on plane at lower speeds. The reason I'm bringing this up is i understand I bought a higher performance deck boat meant to go faster but i didn't realize i would be giving up the "boatability" at lower speeds, sometimes i like to just cruise with the family including 2 babies around 2 yrs. old. thoughts?

Yep 25-30 is about where my nordic deck rolls over. I can keep it on plane down to 20 or so once on. Many people have suggested either hydraulic sponson/trim tabs or a fixed tunnel tab to help it roll over.

 

[Melloyellovector]

Whats Your drive trim at? If already on plane and it’s falling on its face at 35 sounds like trim is up not down

 

[RyanTurn91]

Whats Your drive trim at? If already on plane and it’s falling on its face at 35 sounds like trim is up not down

ive played around with the trim trying to get it to stay on plane but my trim is all the way down

 

[dezertrider]

Even my little stoker goes off plane at 25-30 mph

 

[Ace in the Hole]

Have you considered changing the prop? What pitch are you currently running? Do you happen to have a 24 4 blade around? Im in that size range with a little less power and simmer time that’s the ticket…winter I run a 26….

Trim matters as well

 

[RyanTurn91]

Have you considered changing the prop? What pitch are you currently running? Do you happen to have a 24 4 blade around? Im in that size range with a little less power and simmer time that’s the ticket…winter I run a 26….

Trim matters as well

currently running a max 28P 5 blade

 

[Melloyellovector]

ive played around with the trim trying to get it to stay on plane but my trim is all the way down

What’s newer deck boat? what hull and year
seating lay out will change behavior of hull and certainly where passengers are sitting. Old eliminators and conquest were heavier in the back half And had more seating in rear putting more weight in the back. Newer lay outs created bigger storage areas, dual helms etc put more weight towards center And less seating in rear puts passengers in the front= not great for getting on plane
could be prop, is the 5 blade, max5 or Maximus old style
what rpm is it getting wide open throttle

Edit: max 5 props typically create lift, and they perform best mid and WOT, low rpm your losing the additional lift created by prop and that’s when it’s falling on its face.

 

[DWC]

Have you considered changing the prop? What pitch are you currently running? Do you happen to have a 24 4 blade around? Im in that size range with a little less power and simmer time that’s the ticket…winter I run a 26….

Trim matters as well

Agreed^^^. I’d try a 26 and/or a 24 to see if it helps. You may be able to slow down 5-8mph and keep on plane. If you plan on running down there quite a bit a little weight up front wouldn’t hurt. (Fill up those coolers). Last resort is some tabs for low speeds. Costly, but much easier to stay on plane and easier on the drive.

 

[Javajoe]

I have a Magic deck with a 625 and had to prop down to 24 to pull kids in tubes at slow speeds. Falls off plane going that slow with 26 and 28. Loading up the front helps like they said

 

[02HoWaRd26]

currently running a max 28P 5 blade

That’s a big wheel anytime of the year for that heavy of a boat with 600hp. I’ll buy that prop from you tho lol.

Seriously I’d try a 26 Bravo or possibly a Maximus 26. It’ll really help holding plane as well getting on plane but will lose some top speed. But if you can hold down to 30 you’re doing good really.

 

[n2otoofast4u]

Why do you want or trying to go that slow?

 

[BigAl96]

Hi, coming out of a 1998 Fundeck with a 502 and a Volvo Penta dual prop drive, I bought a newer 28' Deckboat with a Merc 600 and a XR drive with a 5 blade on it, my question is anything below about 35MPH the boat wants to fall off plane, is this normal and to be expected with a higher performance boat? My Fundeck was easy to drive and once on plane was easy to keep on plane at lower speeds. The reason I'm bringing this up is i understand I bought a higher performance deck boat meant to go faster but i didn't realize i would be giving up the "boatability" at lower speeds, sometimes i like to just cruise with the family including 2 babies around 2 yrs. old. thoughts?

I have a stock 24p bravo 1 prop I keep as a spare if you want to try a smaller prop before spending the money. Not sure where you're located, I'm in the phx area

 

[Dcb.blake]

From my understanding the hull is more the deciding factor of when your on or off plane along with speed/weight. Changing the prop will help but it’s not gonna drop you down to 20mph vs the 35mph you’re at now imo. I would for sure drop to a smaller prop and see what happens

 

[02HoWaRd26]

Why do you want or trying to go that slow?

Because not everyone has to compare penis sizes and always go fast, even tho you’re a 3 second go fast guy!

 

[n2otoofast4u]

Because not everyone has to compare penis sizes and always go fast, even tho you’re a 3 second go fast guy!

If you want to go slow buy a wake or a pontoon boat.

 

[fastenuff3]

currently running a max 28P 5 blade

you need a drive spacer.to high x dimension if you want a slower cruising speed.