2008 Mastercraft x2 sways side to side over 35 mph

[bobski]

I just purchased a 2008 Mastercraft x2 and noticed a sway side to side when driving at full throttle. The sway stops when I back off to about 35 mph. Any thoughts of what would cause this? I have done some research but haven’t found anything on this issue.

I have belonged to this forum for years and it has been very helpful for troubleshooting my 88 prostar. I don’t usually post on the forum. Any advice is appreciated.

[robadele]

I would start by seeing if you have any play in your rudder while it is straight ahead and/or if putting a slight amount of turn in the rudder causes the sway to go away. If the rudder is not being held steady, you can get some sway. I'm assuming you get this under all types of water / wind conditions. If you only get it under certain conditions, like a strong headwind, I would not worry about it as much. It is possible that just based on the way you have the boat ballasted that you have a natural frequency in the forces on the hull at these speeds, but I would expect this to change if wind or water (chop) conditions changed. You can try altering the ballast in the boat. For example, but some weight in the very front of the bow and see if things change.

[bobski]

Thanks for the suggestions. The sway happens in any water conditions. If I let go of the steering wheel you can see if move from left to right. My hoist is going in the water tomorrow so once it is on the hoist I can look underneath and check the rudder.

Thank you

[swatguy]

Usually the first place to check with little sway is the rudder, then the steering connection to rudder. If those look good , then usually next step is tracking fins( your boat doesn’t have any) .
There is going to be a substantial amount of noticeable “walk” at high speeds with the x2 vs your old pro star. The x2 doesn’t have tracking fins so it needs a lot more steering corrections to keep it tracking straight than you old boat did and you’ll be be adjusting the wheel quite a bit more. It’s the one knock of the X2.

[Taco47001]

If you let go of the wheel does it want to pull to one side? If not, someone may have balanced the rudder which is counterintuitive. By design its supposed to pull one way so you can apply opposite input and the boat will track straight at all speeds. If material was taken off the rudder to balance it, that could be your problem. My previous 07 X2 wanted to pull left at speed.

[sand2snow22]

Do you have attitude adjustment plate? If so what is the position of the plate when it's walking?

[bobski]

Thanks for the input. I have made some adjustments to the rudder and steering cable which has improved the sway, but it still happens at times over 30 mph. Seems pretty consistent between 35-37 mph. If I let go of the steering wheel you can see it turn back and forth slightly.

I do not have attitude plates.

at lower speeds, 15-25 mph, sometimes you can feel the boat shift from side to side almost like someone heavy moved from one side of the boat to the other.

Thanks for the feedback

[mwenger]

I had an 08 X2 without tracking fins and it would act like you are describing at times depending on speed and conditions. I also had an 08 X-Star that had tracking fins and it was noticeably better.
I always attributed it to the tracking fins making a difference.