a bit of an obvious one but have to check is it fitted with trim tabs ? are there seperate compartments under floor possibly water in one side?

Does it sit level at rest?

Has it always been like that?

Have you measured the outboard mounting bolts to make sure it's all square?

 Adjusting the anode behind the prop 

Does the helm pull either way when you are planning?

 Is the skeg bit on your outboard straight  mine was weird when i took it for a run had a look straightned it up no dramas now

 at home ,level the boat/ transome horizontally and then check if the bolted motor is vertically level , may also need to adjust the skeg slightly off centre 

Prop torque. will also get exaggerated with a high degree of hull angle. Exagerated further if the motor is mounted further to the port side.

Not being rude but do you adjust your engine trim to suit the conditions constantly or are you a trim set and forget type of guy?

 +2 its your motor annode move it

 Fully move over to way it leans. Had same issue with swifty . Also lightens your steering

 Hey guys thanks for all the comments. I will have to pay more attention to specifics next time i am out.

In repsonse to comments

The helm dosn't pull either way when under plane

The skeg looks straight to me but will have to have a closer inspection.

I will have to check the bolted motor to see if it is vertically level.

I am a bit of a set trim and forget guy, i pretty much have it out as far as i can without it reving out of the water. The boat has a deep V and can breach if the motor is too far down plus gives a better ride (apart from the lean). It does tend to lean a bit more into the wind as well

The anode above the prop is set to the centre and always has been, i will try and adjust it it 1 notch to the left and see if it makes a difference as this seems the easier thing to try.

Pretty amazed that trim tabs don't make much difference.......I would suggest they are not actually working if that's the case. I can tip my boat over 30 odd degrees on its side with one trim tab down.....but agree, start with the anode, but check your trim tabs.

You do know the trim tabs up/down labels can be a biut confusing.....they are normally bow up/down, not trim tab up/down.......

I agree with John, if the boat is level at rest then I would put money on your tabs not working or one is bent. 

Plate Ali boats have a nasty habit of leaning into the wind...my 7.5m Genesis does it.  But it doesn't just lean left...it will lean left or right, depending upon wind direction.

I don't have trim tabs, but I can pretty much eliminate it by moving my 200 litre icebox around to suit.

 could be moved 1 is bolted to the motor other to the boat to stop rust , the skeg if its called that is bolted to the motor and designed to be adjusted left or right. 

 Some outboards use the trim tab (skeg) as an anode.

 Is the transducer on the right(starboard) I have seen 1kw trans causing problems. Pull the transducer off and take it for a run. Basically big transducers can act like one trimtab

 Like others said, I'm very surprised you can't trim this out with the tabs. I suspect the left tab is not working.

I think i will have to check the tribtabs then as well

 There is a 1kw transducer on the right as well as a deflection plate to stop the rooster tail.

You have had this boat for quite a while, has it just started happening ? Whats changed?

I was going to say its a trimtab problem when i assumed you had Ql's but i still think one of your trim tabs is broken.

With my new boat i was thinking the same thing but in reality it was just the wind grabbing onto the hardtop and chines.With the bigger motors they can lean to port due to the prop torque. I found when the wind was holding the boat to one side no matter how much stuff i put on one side it would not move. I had to do a run without wind to really work this out. Trim tabs will however help this in the wind!

I have a 1kw transducer starboard side and when i had to too low and a huge rooster tail it was dragging but i have now lifted it, no rooster tail, better results and very minimal dragging!

There are more experts on this than me but i thought the anode was to correct steering and if yours is going dead straight i woudnt mess with it ?

Vinnie

 Fat Deckie?

 So an update, i have gone and checked the trim tabs and both were not functioning, good call for those who mentioned it 

I have managed to free up the port trim tab, although it is still a little noisy,  but the starboard is completely stuck, Is there any maintenance that can be done to free them up or do they have to be replaced.

I have included some links to pics below, for how far the trim tabs are coming out, as you can see starboard side is not at all.

Port Trim Tab 1drv.ms/1OiiAdk

Starboard Trim Tab 1drv.ms/1OiiGll

Also is it still worth adjusting the Anode or wait until i have fixed the trim tabs, photo of anode 1drv.ms/1Oapof6 (Ignore scratches on the area above the prop, thats what hitting plate coral at the Abrolhos does, lucky i had a stainless prop  )

 Fix the trim tabs. The anode is fine if your steering is not pulling. I have no experience with Lenco actuators. Try google them, maybe there are kits out there for them but if they got water in them then they're stuffed.

Dont touch the anode. Pull it apart and have a go. They are about $300 for a new actuator!

 before you go and buy new actuators, get a quote and message me.
Might have something that would help.

 Lenco trim tabs hydraulic or electric? 

Also that tranducer and plate - I've got a 1kw on my current boat and had one on my previous. Just going off the pics, the transducer looks very low. I realise that might be for signal quality, but given the footprint of the transducer, if it is submerged very deep, that in itself would create lift, making the boat lean to port. If it only does it at speed I would suggest that the deflector plate wouldn't be playing much part in the problem, as it would most likely be out of the water, hiding behind the transom, but if it is doing it at lower speeds as well, the plate has a hell for a surface area and that would be adding to the problem. If you are getting a rooster tail, that to me would suggest that the transducer is very low in the water. 

As the guys have said above, your trim tabs could be used to compensate for that. I know on my Bennett tabs, if the hydraulic fluid had air in the line or it was low on fluid, they would be noisy. Not sure if yours are hydro though ?

Check on of my previous posts where I go through how to pull lencos apart and install new o rings. Bit of a pain but fixed mine and for $10 for new o fi fa saved $700 for new trim tabs.

 So another update i pulled  them apart, full of rust and the cogs have snapped, looks like i will be pricing up new actuators

 I had the exact same problem with my 5.3 trailcraft and I fixed it by just adjusting the outboard tilt while driving until it didn't pull to the left anymore

Hope that info helps

Hmmm, snapped cogs are gonna require heavy duty grease......haha.

Mine were full of slat water and starting to rust but got em early enough and used standard marine grease.

The Lenco design is crap, as the extension creates a vacuum that sucks in salt water if the o rings are not 100%....

 Just for an update finally replaced the actuators and tested yesterday can easily level the boat out now, thanks for eveyones advice. It's a pity they cost $350 each :(

 Cheaper than buying a new boat because that one was crooked! ha ha