I have a 2003 222 fisherman and recently repowered with a 2022 DF250AP Suzuki. Original prop from dealer was 16”x20” and could only pull 5000 rpms. Swapped that out for a 16”x17” and now can just crack 5500 rpms at just over half trim. Both props are water grip Suzuki. I also tried an Suzuki 15.5”x17” prop and was able to reach 6000rpms at half trim, but felt the boat was struggling to stay on plane at low speeds. Ordered an Powertech OSF4 17” pitch and could only reach 5700 rpms but ventilated pretty bad offshore. I’m really at a loss and am getting very frustrated. Any suggestions on what prop I should be running would be greatly appreciated.
Grady White 222 Fisherman Prop Help!!
- Thread starter rsacco
- Start date
What are your goals/needs. Do you want to get from point A to point B in the shortest time or is it something else. I kind of smiled when you said your prop ventilated offshore. Does that mean it doesn't ventilate near shore
Was it ventilating or cavitating.
I have no idea what half trim means, please explain. Also it would help to know at actual speeds you are getting at the revs you listed.
In general note that the most optimal rev range for a motor is about 90% of WOT.
Was it ventilating or cavitating.
I have no idea what half trim means, please explain. Also it would help to know at actual speeds you are getting at the revs you listed.
In general note that the most optimal rev range for a motor is about 90% of WOT.
My goal right now is to allow the motor to reach the rated rpms which is 6100. I don’t want the motor to lug and regardless of which prop I put on I seem to get similar performance. I’m looking for best cruise speed and economy with good traction and hole shot. Wot for each prop was around 41 mph with cruise around 28mph at 4100 rpms for the 16x17 and powertech OFS4. The 15.5x17 cruised at a higher rpm to achieve 28mph which was around 4450. Half trim is referring to the trim indicator on the digital gauge.What are your goals/needs. Do you want to get from point A to point B in the shortest time or is it something else. I kind of smiled when you said your prop ventilated offshore. Does that mean it doesn't ventilate near shore
Was it ventilating or cavitating.
I have no idea what half trim means, please explain. Also it would help to know at actual speeds you are getting at the revs you listed.
In general note that the most optimal rev range for a motor is about 90% of WOT.
Rpms were surging when cruising in 2 to 3 foot waves. I can hear it and and see the fluctuation on the gauge. Pretty sure it’s ventilating, although I’ve seen these terms used interchangeably. The traction wasn’t nearly as good as the 16x17 Suzuki prop.
Try again but don't worry about what the trim gauge is saying. The proper way is to keep trimming (calm day) till speed no longer increases or the prop starts to ventilate. THAT is your max RPM. Once you have that, then you can start making a better decision.
I did this for all wot rpms shown and trimmed up until speed stops increasing. Suzuki 16x17 has no change in speed past half trim but I can get rpms to as high as 5750 without ventilating.
There is no reason to insist that your motor makes the high end of the WOT revs. You don't want and shouldn't want to run at WOT for extended periods of time As I mentioned, 10% off of WOT is used for optimal revs as a general rule.
As to the ventilation, the motor is telling you that you are trimmed up too much (assuming the correct mounting hole was used).
As mentioned, don't put a lot of value in the trim indication. Its like the volume know on a boom box. The number doesn't mean much. Typically the maximum trim angle ( from vertical) will be under 10 degrees.
Also be aware that every prop is a compromise in performance. It may be optimized for one parameter like top end speed but not for low end torque etc. .I suggest you document your slip percentage for the various props and speeds. There are online calculators that make the calculation easier. You need to know your gear ratio ( 1.86 maybe for that motor)
As to the ventilation, the motor is telling you that you are trimmed up too much (assuming the correct mounting hole was used).
As mentioned, don't put a lot of value in the trim indication. Its like the volume know on a boom box. The number doesn't mean much. Typically the maximum trim angle ( from vertical) will be under 10 degrees.
Also be aware that every prop is a compromise in performance. It may be optimized for one parameter like top end speed but not for low end torque etc. .I suggest you document your slip percentage for the various props and speeds. There are online calculators that make the calculation easier. You need to know your gear ratio ( 1.86 maybe for that motor)
I was told by Suzuki reps that the motors should be able to reach the higher end of the maximum rpm range under normal load. This would allow the max rpm’s to be in the range with heavier than normal load. In addition, the motor will lug at all cruising speed the same way it lugs at wot so running at wot isn’t the problem.
My gear ratio is 2.08 and the slip on the 16” diameter propeller is amazing around 5%. Similar slip numbers on powertech prop. The 15.5” diameter propeller had a slip number on 16%.
I’m not worried about trim level just stating where I am at when wot.