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Hydra Sports bass boat


chryslr's Avatar
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04-19-09, 08:13 AM   #1  
Hydra Sports bass boat

I recently purchased an '89 hydra-sports VS-150T bass boat. I took it out the other day and when I tried to get on plane the boat bow seemed to raise up very high (this is my first bass boat so I am not sure if this is unusual). When I finally got it up on plane the bow started to bounce up and down on the water, so I slowed back down. Does anyone know what is causing this problem?? I would appreciate any info you can provide. Thanks.

 
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Rick Johnston's Avatar
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04-19-09, 09:31 AM   #2  
Welcome to the forums.

It sounds to me like the motor is trimmed out too high. It should be pretty close to vertical when you take off to get it up on plane.

Motor trim is used to raise the bow when on plane so more of the hull is out of the water. Less boat in the water = more speed, but the point of diminishing returns happens when the trim is raised too much. The motor tries to lift the boat but it can't, so the boat falls back into the water, slows down, and the process starts over. This bouncing is called "porpoising". Not only is it an uncomfortable ride, it also robs you of speed and gas mileage.

 
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04-19-09, 09:47 AM   #3  
The small bass boats won't raise a lot when on plane.
What motor are you running my hydrostream viper also a 15 foot boat with a 150 evinrude porpuses bad with any trim up to about 45mph. If it has a jack plate this will make it worse but it helps with top end.

Welcome to the board

I guess I type to slow rick! great explination though.

 
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04-19-09, 12:17 PM   #4  
hydra sports vs-150t

My VS-150T is 17 1/2 ft with a 150 hp Johnson GT. My boat also has a jack plate and a hot foot. Are you saying I should keep the trim pretty much parallel with the angle of the transom when trying to get up on plane??


Last edited by chryslr; 04-19-09 at 12:28 PM. Reason: This message is a reply to Rick Johnson
 
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04-21-09, 04:00 AM   #5  
Yes. Start with the trim all the way in, then after it gets on plane (if you have power trim) nudge it out until the RPMs increase, but not so much that it starts to porpoise.

Another bad thing with too much lift: the prop can cavitate (catch air) causing the motor to over-rev.

 
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04-24-09, 02:15 PM   #6  
Hydra Sports Boat

Posted By: Rick Johnston Yes. Start with the trim all the way in, then after it gets on plane (if you have power trim) nudge it out until the RPMs increase, but not so much that it starts to porpoise.

Another bad thing with too much lift: the prop can cavitate (catch air) causing the motor to over-rev.
Rick: I am thinking about buying a Stingray Hydrofoil Stabilizer XPI Senior. What is your opinion of a hydrofoil stabilizer?? Do you think it would help to keep the boat more level at lower speed for better vision, and also help get up on plane faster??

 
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04-24-09, 06:14 PM   #7  
I have a low opinion of stabilizers and fixed trim tabs. I've tried them on two of my boats and saw no benefit. Powered trim tabs are useful on the boat I currently own, but only to balance an unbalanced side-to-side load when on plane. The rest of the time they are in the full-up position.

Your issue seems to be caused more by weight distribution/motor trim than to the boat itself. Do you have a lot of gear or people up front when trying to plane? Bait wells and live wells loaded with water?

Don't take this the wrong way ... Have you owned a boat prior to this one? The reason I ask is, in almost every boat the helm loses line of sight directly forward for a few seconds while planing off. It's normal while idling along to scan the waterways from 90 degrees left to 90 degrees right before you open the throttle. The scan will tell you that no boats are approaching, and there is nothing else in your way. Your boat should be on plane within 10 seconds.

It's also common to lose line-of-sight when you're moving above idle, but below cruising speed on plane.

I'm not that familiar with outboards. I'm an I/O owner. In my experience, if the motor RPMs are under about 1400 the boat is considered to be idling. Cruising speed when the boat is on plane is around 3000. If you're running at 2000 the boat's bow will rise and you'll lose line of sight at the helm.

This is also the worst thing you can do for your wallet, since it wastes fuel. The most fuel-efficient speeds are at idle, and backing the throttle after the boat is on plane to just above the point where it wants to fall off plane ("cruising speed"). The biggest waste of fuel is running it wide open.

 
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04-25-09, 10:53 AM   #8  
Hydra Sports Boat

Posted By: Rick Johnston I have a low opinion of stabilizers and fixed trim tabs. I've tried them on two of my boats and saw no benefit. Powered trim tabs are useful on the boat I currently own, but only to balance an unbalanced side-to-side load when on plane. The rest of the time they are in the full-up position.

Your issue seems to be caused more by weight distribution/motor trim than to the boat itself. Do you have a lot of gear or people up front when trying to plane? Bait wells and live wells loaded with water?

Don't take this the wrong way ... Have you owned a boat prior to this one? The reason I ask is, in almost every boat the helm loses line of sight directly forward for a few seconds while planing off. It's normal while idling along to scan the waterways from 90 degrees left to 90 degrees right before you open the throttle. The scan will tell you that no boats are approaching, and there is nothing else in your way. Your boat should be on plane within 10 seconds.

It's also common to lose line-of-sight when you're moving above idle, but below cruising speed on plane.

I'm not that familiar with outboards. I'm an I/O owner. In my experience, if the motor RPMs are under about 1400 the boat is considered to be idling. Cruising speed when the boat is on plane is around 3000. If you're running at 2000 the boat's bow will rise and you'll lose line of sight at the helm.

This is also the worst thing you can do for your wallet, since it wastes fuel. The most fuel-efficient speeds are at idle, and backing the throttle after the boat is on plane to just above the point where it wants to fall off plane ("cruising speed"). The biggest waste of fuel is running it wide open.


Rick, I do not have any gear, people, or live wells full of water up front in my bass boat. I think that is my problem. All the weight is at the rear (150 hp motor w/ jack plate, 25 gallon fuel tank, 3 batteries, and 2 seats for passengers).

No, I have not owned any other bass boat. My only other boat was an old 14 ft. '65 speedliner runabout boat w/40 hp motor and back to back seats. It didn't lift up in the bow like my bass boat does.

I took the boat out yesterday to try adjusting the power trim as you suggested. It would get up on plane the easiest with the trim fully in close to transom. The angle of the motor seemed a little odd, but I didn't have hardly any porpoising problem (the water was a little rough with the wind).

They advertise these Stingray Hydrofoil Stabilizers as being able to lift the rear of the boat to help level out the boat, even at lower speeds. Maybe this is all hype. I don't like the idea of drilling to mount the stabilizer.

It seems my bass boat lifts up a lot when trying to get up on plane. Maybe it just something I need to get used to. There isn't much I can do to distribute the weight more evenly. Any more suggestions would be appreciated from you or any one else on the forum. Thanks

 
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04-25-09, 06:28 PM   #9  
I think a lot of your porpusing is due to the jack plate on a small boat with a big motor. It sounds close to the same set up as my bass boat 15' boat and a 135 etec with a 5" setback jack plate. Before I installed the jack plate it hardly ever would porpus but after installing the jack plate it will porpus it I use too much trim.

You could remove the jack plate and bolt the motor to the transome but you will end up loosing a couple mph on top end.

I'm with rick on the hydrofoil, but I have never tried the same boat with and without one in the water. The guy's I've talked to didn't seam to notace any differance with them.

 
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