boat list

Question
Hi Ron. I have a Savanna 350 (3.5 meter single skin fibreglass planning hull) fitted with a longshaft 30 HP mercury outboard. As the transom was obviously intended for a short shaft the previous owner has modified it with a stainless steel plate. The propshaft axis is 230mm below the bottom edge of the transom and the cavitation plate is 80mm below... is this too low? (Any further raising of the O/B will require complete replacement of steering pulley system) The problem I have is the boat lists to port by about 18 degrees when on the plane. Is this the torque effect from the prop (normal right hand pitched)? I am sure the weight distribution is not the problem. Bilge is dry. Any ideas? Thanks

Answer
Hi Adrian...Thanks for selecting the undersigned to reply to your question.

You didn't mention how long you've owned the boat/mtr. and how recently the listing problem was noticed and whether it was instant or progressive. I imagine the bilge area is open and visible, which is the case with many 11.5ft boats. Unfortunately, I'm not familiar with a Savana 350.

Next opportunity the boat is out of the water, look from the stern along the keel to see if it is warped up and down, or wavy from side to side.

The most important aspect is to ensure the cavitation plate is flush and directly inline with the very bottom of the transom or boat. If substantially higher or lower, it will affect planing and steering.

I find it surprising you have a right-turning prop. Most outboards built in North America turn left, so as to off-set the weight of an operator sitting at the starboard (righthand) helm. In your case, I would have anticipated your boat lists to the right, not the left, which makes it even more difficult to offer any positive guidance.

Best you consult a local marine repair/dealer facility you can trust, and obtain their opinion.

Safe Boating
Ron