Vibration

[Thegerman618]

Hey All,

Ran the boat for the first time this season last weekend, before I explain here is what I have done:
Last Season Prop Shaft Alignment
New Acme 911 Prop (first trip out)
Fresh Fluids all the way around last month
2570 lbs ballast
Running 11-13 mph

It gets up and goes fine no issues, but when pulling back to hold speed and plowing through the water, I get a random vibration from the prop and its not constant. I am very familiar with cavitation as that is why I got the new prop, its not that either. I checked trans fluid, still good no burned smell, Checked the trans Cooler its clean. Could it be I am just not new to the feeling of running this much weight at such a slow speed and just feeling the prop more? Also is there such a thing as transmission cavitation, when I drained the Velvet drive after the fact I pulled almost a full EXTRA quart making it 3 quarts when it calls for 2 quarts. I know this is a Centurion Boat, but honestly shouldn't matter we are all basically running the same motor and velvet drives. Any help is much appreciated.

[chpthril]

Tracking fin alignment?

[Thegerman618]

Tracking Fins are straight and in-line.

[SBM1234]

Did they replace the bushing in the strut when they did the shaft alignment? Might check to see if there is any wiggle room (up-down, left-right) when you move the prop. There should be none.

[Thegerman618]

I will check that when I get home from work, thanks that was one I didn't think of.

[scoot18]

I have had a similar vibration or quivering feeling in mine ever since I got the boat new. It happens when heavily weighted for wakeboarding or surfing, usually right around 1200 rpm's, feel it when turning around to pick rider or momentarily when taking off and getting up on plane. It was checked by dealer and never figured out. They did swap, crank balancer, flywheel with no change. It has been on the forum and discussed with no real resolution. It has become something I have learned to live with. Doesn't do it when not heavily weighted.

[Thegerman618]

Scoot18, yep that sounds exactly like what I got. Glad to hear that I am not the only one that has this. Just cruising around it runs great, out of the hole it is fine, only at surf speed and heavily weighted its relatively light but it is noticeable. Thanks for all the advice everyone.