Vibration or chatter in Steering

[pls4912]

Anyone else experience a slight chatter or vibration in the steering column during the initial take off. It goes away after a few seconds while the boat is planing. Eventually I will change the prop to an ACME 525. Just wondering is there is anything you can do to fix? Suggestions? Boat is a 2005 Mobius LS.
Thanks,
Phillip

[clark]

The last time I was out on the lake in our '05 LSV, I got really nervous. We had been out for 4-5 hours. I had 2 teens behind the boat on tubes. I noticed a vibration in the steering and it sounded funny and as I accelerated, the vibration got very bad. I thought I had somehow messed up my prop or drive shaft. I got them back in the boat and was heading back to the marina. Then I went to WOT and the vibration was gone. I did perhaps think maybe I had gotten some weeds wrapped up in the shaft or prop. No problems for the other couple of hours.

Does anyone have any other theories other than weeds? I never have had the problem before, and I usually do not see a lot of weeds in out lake.

Clark

[pls4912]

Yes, that was my thought also, might be the cause. However, the chattering sound I am feeling is more in the steering than the actual boat and drive train vibrating. I was wondering if there was some kind of grease fitting or a way to lubricate the steering cable. That might smoothen it out a bit. I have also had the problem of picking up something from the water that makes the whole boat shake, I thought I hit the prop on something. Stopped, put it in reverse and the problem was fixed.
Phillip

[seanpatsdad]

pls4912
there is a grease fitten at the rudder were the cable conects to the rudder shaft.
John

[pls4912]

I checked the prop when the boat was on the trailer and it looked to be in good condition. No dents at all. I also put the boat in drive for a few seconds while flushing the engine and while the prop was spinning it appeared to be out of track, not by much though. If something was wrong with the prop wouldnt the vibration become worse as the RPM's increase?

[chpprpilot]

I've had this same problem on my XLV, as well as my Outback LS that I owned for two years. It's a crackling sound like the steering shaft metal is being stressed. It happens every time during hard acceleration, especially when the ballast is full. I've had the drive and steering systems looked at but have found no problems and the sound goes away within a few seconds.
Moomba: Is there a type of insulation that could be installed to at least keep that sound down a little? I know from experience that the boat is working fine, but everyone who rides on my boat looks at me like the boat's about to come apart upon acceleration.

[barefooter200]

Hello,

I have a 93 Boomerang and mine has done this since the start...

I dont know why, but it does anoy me. So anyone with more ideas, like someone at MOOMBA, give us a hand please.

Love the boat, but just a few kinks,....

Jeff

[smokedog2]

Clark,

I think you are cavitating the prop at the yank & bank. Add a little weight. Worked for me.

The rest. No clue. No chatter on my 05 LSV. A SWAG might be a lose mounting bracket for the steering cable.

SD2

[Shoemaker Mobius]

I get steering vibration when I have our 2004 Mobius LSV heavily weighted and pulling up a wakeboarder. However, I find it mostly occurs when the steering is not straight ahead - if I have the steering partially left or right when I hit the throttle, there is much more vibration than when I happen to get it straight ahead at throttle up. When the boat is not heavily weighted, it doesn't happen at all. I am in the habit of guessing that the steering is straight and when I hit the throttle, let the steering wheel slide on its own to a straight forward direction. This has no impact on the wakeboarder because the boat wants to go straight and straightens out very quickly. By heavily weighted I mean the center bag in the ski locker full and approx. 500lbs in each of two bags next to the engine compartment (i.e. 1,000 lbs in the rear), plus 2-5 people on the boat.

[clark]

SD,

Give me more info on the "Yank & Bank". This problem has also happen with the bags half way full and 5 people in the boat.

Clark

[smokedog2]

When I was out with my LSV towing a tube I could yank the steering to throw the tube into a slide out of the wake. By leaning the boat over and pulling around the sound of the boat would change, this is the prop running in the wash off the bottom of the boat which is an air/water mix. Once you put it down the noise goes away.

That is what I found anyway. I filled the center sac and never heard the prop again.

Generally running a prop in air or air/water is bad. At leat that is MHO.

SD2

[Shoemaker Mobius]

Smokedog,
Is what you are describing called cavitation? I have read threads on other BBs that indicated under various conditions and different boats, cavitation can be a real problem, but I don't really know or understand what it is.

[smokedog2]

Yep, one type of cavitation. It can also be caused by poor prop selection, poor trim on an o or I/O, wrong prop for weight etc. My 40 hp Honda will cavitate at top end when empty. The prop is designed to move three guys, two dogs a layout boat and 150 decoys so it "cuts" more. I am no expert but the Board boat is not designed to yank & bank empty. Just add a little weight to keep the prop in the water.

I think porposing is also a form of cavitation.

Where the heck is Brian, he would know better than I would.

Ha I see Brian is still at work - what is your $.02 at this late hours? I will find out tomorrow :)


SD2

[Brian Raymond]

The "chatter" that is felt is caused by turbulent water passing the rudder under certain conditions. This will vibrate the cable inside the sheathing up to the rack at the helm. This makes the gear mesh between the helm and cable also vibrate. This is common on the rack steering system. Brian Raymond

[clark]

Brian,

I spoke to you last week about this happening on my 05 LSV. Took it to the dealer and they checked everything and said the exact same thing in your last reply. They said turbulent water passing the rudder. My dealer did a great job. Took in on Thursday and they were so busy they could not fit me in, however, they stayed late on Friday. I spoke with the service manager at 8:00PM and they had mine ready so I could pick it up on Saturday.

Great job Atlanta Marine. Kurt and Lisa run a great dealership. Thanks to Brian (not Brian Raymond), their service Mgr for fairly quick turn around.

Now, I also give a big thanks to Brian Raymond for speaking with me on the phone last week to help me understand everything that was going on. Oh yeah, one problem they could not replicate is my trailer shakes from side to side at approximately 25-30 MPH. Anyone else having this problem? Other than that, it is a Great Boat.... 05 Mobius LSV.

Thanks Guys.

Clark

[pecanflyboy]

The "chatter" that is felt is caused by turbulent water passing the rudder under certain conditions. This will vibrate the cable inside the sheathing up to the rack at the helm. This makes the gear mesh between the helm and cable also vibrate. This is common on the rack steering system. Brian Raymond

I was in the process of starting a new thread, when I found this one in a search. I'm having the same problem.

Background: 125 hours, 2001 Mobius. Just replaced the steering cable with the Teleflex SSC15418 (I'd recommend the SSC15419 19' cable, as the 18' cable was 10" shorter than the one installed). This cable makes the steering feel like butter...very nice.

Condition: Full throttle, loaded boat, rudder near center. Turbulence or cavitation on the rudder is transmitted from the rudder, to the cable, to the rack, and into the helm. I can actually feel the vibration in the cable when I reach beneath the dash. It feels like a rattle or chatter.

Causes?: It may be just the cavitation, as Brian has said, and it may be normal. However, it is unnerving. I worry that there is too much slop or play in the steering cable clamp block and/or in the clevis where the cable attaches to the rudder control horn. I was able to replicate the feel by moving the clamp block against it's stops where it hits the cast mounting. I don't know if this is what I'm feeling in the helm, or if it is just a vibration coming up from the rudder.

Can anyone confirm that this is a normal condition? I really don't want to spend the $$ on a new clamp block and clevis only to find out that it's not a problem.

Jimmy

[pecanflyboy]

https://forum.moomba.com/showthread.php?t=14645

This was the thread I'd created about replacing the steering cable.

[deafgoose]

Check how much "play" you have in your clamp block. Mine needs to be replaced also.

[pecanflyboy]

Check how much "play" you have in your clamp block. Mine needs to be replaced also.

There isn't much "play" in the ball and block, other than it's ability to rotate freely around the ball.

[saskie99]

Last summer I had the same problem, it was a slightly bent prop and the locking nut had slid down the shaft and prop was not super tight on the tapered shaft. I put a rebuilt prop on and all my problems went away once it was seated properly on the drive shaft.
It my sound like I negected my boat but is sits on a lift and I never had it on a trailer all summer so I was just something I never thought to check.

[pecanflyboy]

Last summer I had the same problem, it was a slightly bent prop and the locking nut had slid down the shaft and prop was not super tight on the tapered shaft. I put a rebuilt prop on and all my problems went away once it was seated properly on the drive shaft.



Great idea. At the beginning of the summer I had my prop rebuilt and installed it recently. I checked, it's tight and the prop and the shaft are running true. Still trying to figure out if this is just normal for a rack steering system.