Boat is fine on plane, it is a snake at dead idle.

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May 27, 2013
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Is this normal for an 18' Seaswirl Sierra open bow to do this near weight capacity? All the people sit ahead of the engine, there is a bench seat across the back. This boat has a 5.7 and a 800 drive. The boat actually is more predictable in reverse than forward at idle in gear. :confused:
 

Howard Sterndrive

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Re: Boat is fine on plane, it is a snake at dead idle.

have you operated any other single prop i/o boats to compare this one too?
generally the low speed wander is pretty much normal- lowering trim tabs help on some hulls, different props can help too
 
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Re: Boat is fine on plane, it is a snake at dead idle.

No, I have only had an outboard before this. I have tried the trim up and down with no change. I see why people use a bow mounted trolling motor.
 

bruceb58

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Re: Boat is fine on plane, it is a snake at dead idle.

Don't over correct. Its pretty normal.
 
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Re: Boat is fine on plane, it is a snake at dead idle.

Thanks, we have gone out 4 Mondays in a row. This was the first time doing a little drift fishing, it idles way to fast to troll without a plate. It wanders so bad I am afraid to try a plate, maybe a bow troller.
 

jerryjerry05

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Re: Boat is fine on plane, it is a snake at dead idle.

Is there any slop in the steering?
Any loose components?
Trolling.What's the rpm/s in gear?Should be about 600.
Adding trim tabs can help with the wander(not a cheap fix).
 
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Re: Boat is fine on plane, it is a snake at dead idle.

Another thing to consider is the small tab/anode on your out drive. It should be right above your prop.

It's there to help correct torque steer (as well as help to prevent galvanic corrosion) and if missing or broken off, might lead to a tracking issue at slow speeds.

You might just be over correcting as mentioned earlier.
 

bruceb58

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Re: Boat is fine on plane, it is a snake at dead idle.

The tab has pretty much no affect at low idle speeds.
 
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Re: Boat is fine on plane, it is a snake at dead idle.

I'm guessing that it's an older boat with a fairly deep V hull. The 5.7L makes it pretty heavy too. All of that serves to make it more "tippy" when stopped and it Porpoises and snakes at idle speed.
The reason I can relate is that I had an 85 Celebrity 21' open bow with a 5.7L. Big, heavy boat. Squirelly as can be at slow speed. The answer is trim tabs. What they are fully down they stabilize the boat at slow speed. the problem is that the cost for hydraulic tabs and the retrofit can be way, way too expensive.
The ultimate solution for me....Nauticus Smart Tabs. SMART TABS raise your performance expectations. After doing a lot of research on this site, I bought a pair from them online. Very easy to install. A couple hours for me...Mr overly anal I'm scared to drill a hole in my hull boater. I even called them with questions and they were very helpful. Smartest move I ever made. The boat stopped moving and the other effect is that it came up on plane a lot quicker when pulling skiers. Awesome product. Just do a search on this site and you will find tons of recommendations
 

Boomyal

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Re: Boat is fine on plane, it is a snake at dead idle.

I am with JJ here. SmartTabs all but eliminated the low speed bow steer/wander in my 20ft V8 runabout. They made a new boat out of it in other ways as well.
 

bruceb58

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Re: Boat is fine on plane, it is a snake at dead idle.

Not sure why the wander is that big of a deal. Hold your hand on the wheel and let it go back and forth a bit.
 

Boomyal

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Re: Boat is fine on plane, it is a snake at dead idle.

Not sure why the wander is that big of a deal. Hold your hand on the wheel and let it go back and forth a bit.

At least mine would never self center, at least in narrow confines.
 

Bondo

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Re: Boat is fine on plane, it is a snake at dead idle.

Originally Posted by bruceb58
Not sure why the wander is that big of a deal. Hold your hand on the wheel and let it go back and forth a bit.

At least mine would never self center, at least in narrow confines.

Ayuh,... The only time mine is an issue is comin' into the slip, cross current, 'n wind, 'bout 20' out,..... :eek:
 
Last edited:

Grub54891

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Jun 17, 2012
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Re: Boat is fine on plane, it is a snake at dead idle.

Grab the drive,when on the trailer,move it back and forth. Is there a lot of play before it moves the steering arm? If there is ya need to repair the steering pin.
Grub
 

DXN

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Jun 21, 2013
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Re: Boat is fine on plane, it is a snake at dead idle.

I have a 19' bow-rider that wonders pretty bad sometimes. Its my first Vee and it took some getting used to. I've noticed a few things that help. Id check what Grub said too, at high speeds the force of the water will help keep the drive straight so you might not notice the play.

Just relax your not going to lose much headway if you wonder several feet of course, and people watching cant really tell so you don't look silly.

Don't trim all the way in. My trim gauge doesn't work so i was trimming all the way down every time I came off a plane so I new where I was starting. I started trimming up to about level and I think it helps allot.

Ask people to stay in one place. moving around makes the bow cut different. I usually just deal with it, but sometimes it gets annoying.
 

Boomyal

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Re: Boat is fine on plane, it is a snake at dead idle.

I can almost guarantee you that you do not have excessive play in your steering. It is the nature of of a semi/deep vee hull trying to steer from the front. Get some trim tabs of some nature and this discussion will come to an abrupt halt.
 
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Re: Boat is fine on plane, it is a snake at dead idle.

Thanks, there is no slop in the steering, it has OMC power steering not OMC Truecourse. It is only 4 turns lock to lock and has the feel of an old Chrysler box if you guys are that old. I will try some trim tabs, thanks for the quick responses. This boat only has 350 hours on it and is a blast to drive above idle. It jumps to plane even with the wife and grandkids in it, can't wait for a smooth morning run with just me to see what it will do.
 

Gangly

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Jan 3, 2013
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Re: Boat is fine on plane, it is a snake at dead idle.

This usually has a simple solution, trim your engine higher and go slightly quicker.

The force of the water acting on the front end of the v-hull is greater than the force applied to the water by the outdrive resulting in the front of the boat steering the boat regardless of the input from the rear. The easiest way to correct the scenario is to lessen the forces pushing on the front of the boat or increase the forces that the steering mechanism exerts onto the water.

To lessen the forces applied to the front of the boat, dont let the front sit so low in the water. To do this at low speed you need to trim up your motor to lift the front end higher in the water column.

To increase the forces applied by your steering mechanism (outdrive), increase your speed which creates an increase in flow across your outdrive which will stabalize it.

Its just the nature of the beast with big heavy v-hull boats, especially when loaded down.
 
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