Planing trouble with an '02 15' Sea Pro

[MJLos]

I just got an 02 Sea Pro 15' with a 50hp Yamaha 2 stroke. The capacity plate allows for a 70hp so I'm hoping my problem isn't this thing being underpowered. I do get the boat to plane but only after a good 30 or 40 seconds, in rougher water the boat really slows down. Today was just me and the wife, not even a full tank of gas and it just takes forever to get on plane and up to top speed. The dealer checked everything, even sent his mechanic who took it out himself and says everything's fine.

So now the questions: is this a poorly designed boat, which would be a good reason why Sea Pro went out of business or is this thing just flat underpowered? Lastly, short of buying more horsepower, could a hydrofoil help?

Any thoughts would be greatly appreciated. Thanks!

 

[Mi duckdown]

Re: Planing trouble with an '02 15' Sea Pro

A boat should get on plane in less than 5 seconds. someting is wrong. I don't think a hyro will help. Got Pics of your setup. What is rpm and GPS speed at WOT

 

[Home Cookin']

Re: Planing trouble with an '02 15' Sea Pro

sea pro is a good design--pretty generic. Is your hull the deep V or modified/bay boat?
don't get a hydrofoil; will make things worse.
Are you dragging the stern/bow way up while trying to plane?
use your trim. start by trimming the motor all the way down, then lift up some once you're up.
move some weight towards the bow, starting with your wife, but best not to refer to her as "ballast."

 

[Chris1956]

Re: Planing trouble with an '02 15' Sea Pro

A 15 footer with a 50HP motor should plane quickly and hit close to 30 MPH at full throttle. Something seems wrong. A 50HP motor on a hull with a max rating of 70HP is just fine. It should have plenty of power. Have you checked to see that you have spark and compresion to all cylinders?

 

[MJLos]

Re: Planing trouble with an '02 15' Sea Pro

A 15 footer with a 50HP motor should plane quickly and hit close to 30 MPH at full throttle. Something seems wrong. A 50HP motor on a hull with a max rating of 70HP is just fine. It should have plenty of power. Have you checked to see that you have spark and compresion to all cylinders?

The fastest I've gotten it to go is about 23mph (sorry, don't have a GPS, that's the reading on the speedometer) at 4100rpm, that's full throttle, no more room to push the lever. The dealer checked compression and assures me its fine. The dealer mechanic also used a GPS and said he reached about 30mph.

Its a deep V hull. I've been leaving the boat trimmed all the way down so I'll trim up a bit once I'm finally planed. I spoke to someone from the dealer today (D & R Boats in Green Brook, NJ) who said the same thing about the trim and he also mentioned the prop, which I don't know the specs of but will get it if it doesn't rain anymore this week. My guess is the prop is too big, perhaps purchased by a "bigger is better" type of guy. The gentleman on the phone today said a smaller prop could add 200 to 400 rpm and trimming up a bit once planed could get me another 200 to 400 rpm. That still doesn't get me to the 5700 or so I'm supposed to be getting (according to a performance test to a 50TLRC by Yamaha on a similar boat. I have the 50TLRA)

Ugh...thanks for your input everyone, it's very helpful.

 

[crabby captain john]

Re: Planing trouble with an '02 15' Sea Pro

The best prop plus using the trim properly should gain about 500 - 600 RPM. Still far from the 5500 - 5700 you should be able to get. There may be an adjustment needed on your throttle linkage too. 1st is easy-- work the trim, then the prop working with a good prop shop. See where that brings you as you may be in range at that time.

 

[jestor68]

Re: Planing trouble with an '02 15' Sea Pro

You need a prop with about 6 inches less pitch than what's on there. Your rpm range is 4500-5500.

Check the size of your prop and go get another one.

 

[MJLos]

Re: Planing trouble with an '02 15' Sea Pro

You need a prop with about 6 inches less pitch than what's on there. Your rpm range is 4500-5500.

Check the size of your prop and go get another one.

The dealer, D & R Boats in Greenbrook NJ gave me an 11 3/8 x 12 aluminum prop to swap with the 10.5 x15 stainless steel that came with it. It made a world of difference. I lifted right out of the water in the 5 seconds that it should take to get going. I got the 5600rpms I was expecting. I didn't change anything else. The new prop gave me another 1000 rpms, which is remarkable.

Thanks to all for your help, this thread definitely lead me to getting a new prop and saved my sanity in the process.

 

[smokeonthewater]

Re: Planing trouble with an '02 15' Sea Pro

glad u got it going... now for TRUE justice, the "mechanic" needs to flipping burgers because he has no business working on a boat. He should have given you this answer from the start.

 

[Chris1956]

Re: Planing trouble with an '02 15' Sea Pro

What was that SS prop originally from? Normally the diameter would not change so dramatically, when the pitch changed. i.e. two props for the same motor will have pitches differing by 2". The props would be 12-3/4 by 21P and 13 by 19P. That is normally what you will see in prop families.