Ribeye leaning to Port when under power

[Depdawg]

Hi, just enjoying our recent purchase of a 2012 Ribeye 785s and have noticed that she is leaning over to port when under power regardless of tide/waves/wind conditions….so much so that the rear tube is bouncing in the water when we ride through slightly bigger waves. I have tried trimming right up and down and in between, but nothing seems to sort it. We have looked under the boat and cannot see any damage.

Is this to do with the propeller pitch or something else? I am a newbie so not experienced i am afraid. Thank you for any help.

[C2 RIBS]

Down to engine trim. Trim up at speed

[Depdawg]

Thank you C2 Ribs. I will definitely make sure the engine is trimmed up when we are out this week.

[Adam and Hayley]

I’ve had exactly the same problem as depdawg on a Humber ocean pro 6.3 150 and I’m very grateful that there appears to be an answe

[emoji106][emoji106]

Can you explain why this down to trim please?

[Voodoo]

Torque reaction of the hull from the prop when its trimmed in too far for the speed I believe.

[Pipster100]

If your RIB is sitting flat at rest and it's not a weight issue causing the port trim, I'd look at the skeg anode, usually there is a fin that you can trim to counteract the rotational force from the prop. As your prop rotates clockwise (going forwards) as well as providing forward thrust it also induces a rotational force. Excuse my very quickly drawn sketch but you'll see the point I'm trying to make. If you slacken the bolt off that attaches the skeg anode try rotating it a few degrees to starboard from the centreline, this should make a difference, if this improves it then trim it to stbd until you're happy with the balance. When everything is i balance the RIB should also track pretty straight once on the plane.

The up/down trim shouldn't impact port/stbd trim but I could be wrong.

[GuyC]

Boating Performance

Quite a good article including the impact of trim on torque induced steering.

[gtflash]

Is your engine mounted dead centre? Is your boat weight biased port or starboard, I would always mount most of weight starboard to counteract prop torque. Battery, helm, oil etc.

As others have said over trim in can cause the port lean or an engine too low on the transom

[vitalspark]

Could there also be some water in the hull and torque reaction then shifts it to the port side where it stays there until you come to rest?

[Limecc]

Take a look at this:
www.rib.net/forum/f45/willard 7m seaforce repower

Changing the prop reduced the dangerous torque roll. The effect must be influenced by the shape of the propeller thrust.
See also:
Propeller Basics Pt3

[Depdawg]

Thanks Voodo.

[Depdawg]

Originally Posted by Pipster100

If your RIB is sitting flat at rest and it's not a weight issue causing the port trim, I'd look at the skeg anode, usually there is a fin that you can trim to counteract the rotational force from the prop. As your prop rotates clockwise (going forwards) as well as providing forward thrust it also induces a rotational force. Excuse my very quickly drawn sketch but you'll see the point I'm trying to make. If you slacken the bolt off that attaches the skeg anode try rotating it a few degrees to starboard from the centreline, this should make a difference, if this improves it then trim it to stbd until you're happy with the balance. When everything is i balance the RIB should also track pretty straight once on the plane.

The up/down trim shouldn't impact port/stbd trim but I could be wrong.

Attachment 137821

Thanks Pipster. Your diagram and explanation are really helpful. Will try adjusting when I am down at the weekend.

[mhill]

Ribeye you say, which way is the lean?https://www.facebook.com/groups/6868...9068999610791/

[Depdawg]

Originally Posted by gtflash

Is your engine mounted dead centre? Is your boat weight biased port or starboard, I would always mount most of weight starboard to counteract prop torque. Battery, helm, oil etc.

As others have said over trim in can cause the port lean or an engine too low on the transom

Thanks GTflash. I believe it is mounted dead centre along with batteries, helm etc.Useful to know about placing more weight on starboard too.

[Depdawg]

Originally Posted by mhill

Ribeye you say, which way is the lean?https://www.facebook.com/groups/6868...9068999610791/

Hi mhill. Thanks for the link...lmao here. The lean is to the left as in the picture on FB!! Not sure we have experienced it that bad yet...shows the importance of always wearing a kill chord!

[Depdawg]

Originally Posted by vitalspark

Could there also be some water in the hull and torque reaction then shifts it to the port side where it stays there until you come to rest?

Thanks vitalspark. Have not noticed water in the hull yet and will look out for this. Cheers.

[Depdawg]

Originally Posted by Limecc

Take a look at this:
www.rib.net/forum/f45/willard 7m seaforce repower

Changing the prop reduced the dangerous torque roll. The effect must be influenced by the shape of the propeller thrust.
See also:
Propeller Basics Pt3

Thanks Limecc. I have a spare prop so my try that out to see if there is a difference. The link is really useful-much appreciated.

[Depdawg]

Originally Posted by GuyC

Boating Performance

Quite a good article including the impact of trim on torque induced steering.

Thanks for sending this useful link GuyC. Lots to learn....

[Limecc]

Originally Posted by Depdawg

Thanks Limecc. I have a spare prop so my try that out to see if there is a difference. The link is really useful-much appreciated.

You want one with a high rake and one that's not sold as giving stern lift, this should produce a narrower cone.

Also GTflash mentioned it already, make sure the engine is set optimally as high as possible while giving no prop ventilation.

[Depdawg]

Have spoken to Ribeye today and they have that the solution is to trim it to half way (on the electronic pitch gauge) and this should solve it. Will update once I have done this.

Thank you for everybody’s helpful comments and advice. Much appreciated.