Boat Corners Poorly - Why?

[rainylakefisher]

I have a 2004 Alumacraft Navigator with a 115 Johnson Fourstroke on it that corners poorly in my opinion. In any significant turn, the prop starts to cavitate and the boat doesn't turn well. The boat has an aftermarket hydrofoil added by the previous owner.

My past boat experience was with a smaller boat with a 40 HP motor. It would 'dig' the water much better even though it was a lot lighter. I have to adjust trim a lot to improve the handling.

More background data:

Aluminum prop ... not sure of the pitch.

Top speed is about 40 mph (GPS tested) with one guy. 38 mph with three people.

Hole shot is fine as long as trimmed down completely.

[CAMAN]

Id remove the hydrofoil and see if it helps. Otherwise to me it sounds like the motor is too high. I'd consider lowering the motor one hole if the hydrofoil isn't the issue.

[Sonicrunch]

+1

[TruthWalleyes]

+1

See this a lot with wide boats, or a shallow motors.

Mine also has the same problem as yours...but i just don't care, or need to corner that fast.

[BoxMN]

Put on proper pitched and proper model SS prop for that combination. Only way to find the "proper" prop is testing. That will solve your problem, and most likely other problems you don't even realize you have yet

Good luck.

[gdog]

One thing you might consider is putting oon a four blade prop. I had similar problems that you describe, I put on a four blade SS prop with a little lower pitch and now I cannot cavitate in a corner unless I have it wide open and turn it as sharp as I can. I think I lost about 1.5mph off the top end but the controllability of the boat was well worth it. In reverse it is really noticeable too. I would think that an aluminum would provide the same results and be a lot cheaper.

[RebelSS]

Id remove the hydrofoil and see if it helps. Otherwise to me it sounds like the motor is too high. I'd consider lowering the motor one hole if the hydrofoil isn't the issue.

+ 3

[JohnMickish]

My Pro V acted the same with the stock aluminum prop. I put on some cheap 17" pitch prop and it took care of all of those issues. Removing the hydrofoil for a test would be the cheapest/easiest thing to try but I'm going with a new stainless prop to cure your conditions.

[Northlander]

Put on proper pitched and proper model SS prop for that combination. Only way to find the "proper" prop is testing. That will solve your problem, and most likely other problems you don't even realize you have yet

Good luck.

X2. Once I went to a stainless prop my boat cornered much better.