Outdrive shakes violently

[bcomer]

1996 5.0 Volvo Penta Duo Prop

At times when tilted up (not all the way) even if in neutral the outdrive goes into a scary shaking back and forth causing stering wheel to rotate back and forth violently and shaking entire boat. This stops if trimmed back down or engine is shut down. If retarted with drive trimmed down the problem does not repeat.

The drive is in very good condition. Was totaly rebuilt last year. Problem existed before rebuild and after.

What could be causing this?

 

[Zackman]

Re: Outdrive shakes violently

Just a little confused on your last two sentences in the first paragraph. Are you saying, if you shut down the motor, restart the motor, and trim back up it doesn't occur? Or are the only two factors required to produce the vibration; 1) the trim is up above some point and 2) the motor is running?

 

[bcomer]

Re: Outdrive shakes violently

The situation only oours with drive trimmed up at least half way. I can only stopped the shaking by shutting down engine or trimming down.

I would estimate the shaking would be about a half turn of steering wheel in both directions.

 

[Zackman]

Re: Outdrive shakes violently

I would think it could be either the u-joints or coupler. Does the engine shake too? Maybe the motor mounts?

 

[Don S]

Re: Outdrive shakes violently

What model outdrive do you have? Volvo used both the older 290 style drives and the new SX style in 96.

Have you removed the drive and checked the ujoints?

Has it always done this, or did it just suddenly start, and how long have you owned it?

 

[bcomer]

Re: Outdrive shakes violently

I have only owned it for a couple years. It started last year before drive was rebuilt (for other reasons). The engine has been rebuilt sine as well (other reasons). Problem occured before either drive or engine were rebuilt. I would hope if the negine and drive were rebuilt (at different times) the joints would have been checked but don't know for sure.

I don't think it has always done this as I had run the boat for months before ever havine problem.

If it matters the poer steering had a leak for some time and would pumped the fluid into bildge until dry. I did run the baot for some time without fixing power steering.

 

[bruceb58]

Re: Outdrive shakes violently

The drive is going to vibrate a bit more when tilted and I think that combined with air in your power steering system is causing your shaking.

Have you tried bleeding the power steering by turning lock to lock?

 

[bruceb58]

Re: Outdrive shakes violently

The drive is going to vibrate a bit more when tilted and I think that combined with air in your power steering system could be causing your shaking.

Have you tried bleeding the power steering by turning lock to lock?

As a test to determine if it is the power stering, you can disconnect your power steering belt and see if the shaking is still there.

 

[Don S]

Re: Outdrive shakes violently

First of all, you shouldn't be running with the drive half way up, if you need to because of shallow water, do it below 1200 rpm. Between over tilted and turning against the lock, it's not a surprise it shakes.
Since you had leaks in the power steering system, you need to bleed the system BEFORE you start the engine.
Fill the reservoir and turn the wheel lock to lock several times with the engine NOT running.

 

[Autotech1]

Re: Outdrive shakes violently

But he didnt say anything about turning it to full lock tho. sounds like a very bad u-joint (or possibly the coupler?). Id wager its time for new joints and bellows.

With the amount of money and time uve spent on this boat id say its a good idea. Some mechanics dont like to look at what theyre not specifically working on.

Did you ask them to diagnose you shake? Have you corrected the power steering problem and still experience the shake?