Counter rotation drive pulling left

[Sinko]

Just picked up a 1990 Sunbird Corsica 175 with 3.0L OMC. Took it for a cruise and found it pulls left extremely hard when moving at higher speed. Low speed no problem. A couple things worth mentioning, found the prop to be counter rotational or left? Lower unit was rebuilt by previous owner through marina after hitting a rock. Assuming this rebuild was available. Prop totally rebuilt on this drive (looks new). Throttle moves forward for forward, etc. What can I do about the hard left and should I be concerned about the drive rotation?
Worth mentioning: I have played with the trim tab. Direction is tricky. Natural instinct is to have the back end facing right to compensate but the past forums say go direction of pull. Marina also told me to trim motor up a bit when running higher speed to take the left push out a bit. The skag is bent to the right when standing behind prop which make me wonder about the hard pull left.
Any input would help to rectify since it is a bit tense trying to hang on to this thing as well as turn right.
thanks

 

[MikDee]

Re: Counter rotation drive pulling left

On Plane, Clockwise (normal) prop rotation, makes a boat pull to the right. Conterclockwise prop rotation makes a boat pull to the left, all you can do is turn the trim tab above the prop to the left (/) looking at it from above. This way, with the water flowing over the lower unit, it will force it to turn right some, helping to counteract left pulling steering torque.

With standard (Clockwise) prop rotation, you move the tab to the right (\) to counteract steering torque.

By the way, when going on plane, or falling off plane, and at low speed, you might notice a slight wiggle of the helm, due to gaining prop torque, or loosing it.

 

[Sinko]

Re: Counter rotation drive pulling left

Thanks,
Would straightening the skag help? It currently is bent to the right (when looking from behind the boat). Would that direction of bend cause the boat to go left?

 

[MikDee]

Re: Counter rotation drive pulling left

Thanks,
Would straightening the skag help? It currently is bent to the right (when looking from behind the boat). Would that direction of bend cause the boat to go left?

Well I guess it depends on how much it's bent? But Yes, it would cause it to pull to the left when under power if it's bent in that direction,,, I don't know how, or even if, you can straighten out the skeg without breaking it

 

[Sinko]

Re: Counter rotation drive pulling left

It's really my only shot at taking the left pull away. It is really difficult to drive with the pull since it is so hard. It's also really difficult to turn right at high speed. I've heard that some marina's may heat the fin up and try to straighten it. It's got a decent hook to it so it will be a tough try.
Say in a worst case scenario (breakage), how much does the lower piece of the drive cost to replace...if possible?