Weaving/porpousing at low speeds

[Beer Thirty]

I've noticed that the I/O style boats like to wander while idling around the lake. Its not so bad with the trim all the way down but theres alot of shallow spots on the lake that require the trim most of the way up.

I've also noticed that its not so bad if you just let it go. Try to over correct and it looks like your drunk and can't drive straight lol.

What can be done to cure/aid the problem?

 

[Hampton]

This is a common problem. I'm not sure there's an easy solution other than either letting it go, or, getting used to the pattern and leading it a little to dampen out the oscillations. Once you get really good, you won't even think about it and no one will notice it. There may be some modifications you can make, but if there are, I don't know what they are.

Be sure that you're only using the 1st trim button to raise the drive while idling around, not the trailer switch.

 

[fwebster]

Its called bow steer and it is normal with I/O's and larger boats. The boat driver makes the problem worse by expecting a faster reaction to steering input and he ends up over correcting. It sounds silly, but try looking further ahead and steering towards a point more distant than worrying about the space 10 ft in front of the boat.

 

[tobnpr]

With the drive trimmed up, it becomes very difficult avoid. Not only do you lose the rudder effect of the drive itself, the direction of propeller thrust changes. Direction changes from more or less horizontal with the drive trimmed in, but becomes more vertical (directed upwards) as you trim up.

 

[bluebelly]

The weaving will all but disappear if you trim the outdrive so that the propeller thrust is on a perfect horizontal plane with the keel of the boat.

Hope this helps.

 

[Nehalennia]

I have also heard that if you have trim tabs, installing vertical "edges" to the tabs, assist the bow steer.

 

[fc3]

Could be the beer, too

 

[Nehalennia]

Could be the beer, too

Beer should straighten that out, with a slower reaction and all.


Now whisky, that may be an issue

 

[Beer Thirty]

ya know, i do tend to forget about it after a beer or two.

It sounds like something im just gonna have to get used to and deal with. Thanks for the suggestions/info.

 

[First Born]

Kinda going along with what Frank said, I point the boat the direction I want to go and then make no adjustments. The boat will wonder to the left and then come back to the right but really is going straight towards the place that I am pointing it. You have the solution, make no corrections. You will notice it will take care of it on its own.

Wesley

 

[Groucho]

I read somewhere awhile back that the weaving is caused by pressure building on one side of the stern, near the outdrive....releases then builds on the other side and on it goes...not much you can do other than if you get the speed till it's almost pushing to start on plane.

 

[uraldyx]

Kinda going along with what Frank said, I point the boat the direction I want to go and then make no adjustments. The boat will wonder to the left and then come back to the right but really is going straight towards the place that I am pointing it. You have the solution, make no corrections. You will notice it will take care of it on its own.

Wesley

This is good info. I was wondering how to correct this. My dad's boats I grew up driving were outboards and now an inboard(charter boat) and twin IO's(cruiser).

 

[douglee25]

I believe you have the newer alpha 1 on your boat setup. On the very back of the drive you should see a trim anode which probably will be the flat style in this case. I believe you can purchase the fin style anode if it doesn't have one to help offset the wander (check your prop clearance). If indeed someone already swapped out the flat style for a finned annode, it can be adjusted by setting the tab about 10 - 30 degrees from inline with the keel.

Doug

 

[Gunn]

I have this same issue. Sometimes I can just let it go and my boat will generally head in the direction I want. But sometimes it acts like it wants to travel into a very sloppy circle!

Has anyone ever tried those hydrofoil winged things you attached to the outdrive? Supposed to eliminate porpoising, quicker planing, etc. Never actually heard from someone who had one if it really helped as advertised or not.

Tom

 

[midway]

Gunn, I used a hydrofoil on my old boat, never did like it. It did get me on plane quicker but that was about all. I have Smart Tabs on my current boat and they do everything they are advertised to do. You just gotta drill holes in your hull below the waterline. :grin: