Vibration at initial throttle

[Bch53211]

I’ve noticed a quick vibration which seems to be located in the steering column at initial full throttle start to get a surfer out of the water. After a second or two it subsides. Any idea what this could be?

[Emilware]

I have that too on my 2021 mojo. It’s really noticeable with a full load at take off while the rudder is turned.


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[zabooda]

Probably prop wash including cavitation air bubbles passing the rudder when throttling up.

[HFarr]

My 2021 will do it with a full load when I have the rudder turned full. Straight it does not


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[Bch53211]

I don’t think it’s cavitation, it seems to happen every time now - almost seems like something could be unbalanced? Might be a little less noticeable when rudder is straight for me too

[sandm]

had a few boats that did this over the years and as zabooda calls out, usually due to having the rudder turned while fully loaded up and heavy acceleration.
if it's happening every time, might check the blade for a ding, rudder or shaft play. had a blade that hit a rock and had a slight vibration to it until fixed that was similar to cavitation and would vary with rpm becoming more and less noticeable as I moved through the rpm range.

[Bch53211]

I think this is likely the cause - when you say the blade do you mean the rudder? I bottomed out the boat in a sandy / gravel are right before this started happening.

[sandm]

if you bottomed out, I bet a soda you have a slight tweak in your prop.
happened to us bottoming out and hitting a small rock. tweaked it enough to do what you are experiencing but was hard to see the slight bend in one of the blades.

[haknslash]

You if you bottomed out likely have a slight bend or Knick in the prop. I had fishing line wrap around my shaft once and it caused all sorts of vibration.

As far as vibrations or rough steering while turned and heavily ballasted I’d say that’s normal. I try and make a point to not accelerate hard while turning from a stop if loaded down.

[Bch53211]

Yeah I figured I tweaked the prop a tad . I’ll have it looked at and repaired if necessary over the winter. Thanks for the input as always guys.