2023 R25 engine height

[Dream Catcher]

I took delivery of my 2023 R25 last month and have been having a fantastic time with it. While cruising at 42-4600 rpm we traveling at about 25-30 mph. When I trim the motor up a notch or two, sounds like the prop begins to cavitate. When I run with the motor all the way down with just one bar of trim on the dash, it seems to be ok until I roll into a semi tight turn or cross moderate boat wakes, cavitation or “ventilation” return. Could the motor be too high? Would a “Dolfin or Hydrofoil” on the cavitation plate help? I asked about this experience I’m having in another forum and found another R25 with similar situation. Thanks for any suggestions. Dave

 

[BB marine]

Dave, you are asking in the right section.( Ask The Ranger Factory) They should be able to tell you the proper hole for correct engine elevation. I'm sure they have tried and tested different hole mounting heights. The higher the better for performance. A well designed hull should have no need for bolt on enhancements. Choosing a proper prop can help more. Hopefully the Ranger folks can give you a complete report on engine hole elevation, maximum trim angle without blow out, speed and rpm for plane. I do know that engine elevation on the Cutwaters outboards has given some owners issues. Prop slip has been an issue. I spoke with a few owners that were working with the factory to correct the issue with mid range slippage. Weight distribution will help too.

 

[Dream Catcher]

Thank you, we will wait and see what they say.

 

[Andrew Custis]

Hello,

This boat is unique from the rest since it has the additional running surface of the "pontoons" that extend past the transom. They introduce a little more disturbance in the water that would cause the engine to cavitate easier than the others without this style of hull. The benefit is stability and economy. So, with this being said, leave the engine trimmed down when you are running. Also, I am used to seeing these boats loaded down in the stern. I am sure the extra weight will also help.

Hope that helps!

 

[Dream Catcher]

Hello,

This boat is unique from the rest since it has the additional running surface of the "pontoons" that extend past the transom. They introduce a little more disturbance in the water that would cause the engine to cavitate easier than the others without this style of hull. The benefit is stability and economy. So, with this being said, leave the engine trimmed down when you are running. Also, I am used to seeing these boats loaded down in the stern. I am sure the extra weight will also help.

Hope that helps!

Andrew,
With that being said, would it help to lower the motor to the next and final hole? Would a dolfin or hydro plane work to help this prop slip? Running with the engine down now isn’t a huge problem for me because I’m in a very calm river for now. What happens in a rough or confused seaway? The boat will be moved to Long Island Sound in Ct. next year.

 

[Andrew Custis]

We have not experienced issues with running the R25 the way the engine height is set therefore we haven't done any other testing. I would not change anything about the boat other than making sure you keep the tilt on the engine to its lowest point.

 

[Robvic]

We have an R25 OB. With one or two people on board, 1/2 tank of gas and zero trim tabs, we will only experience cavitation when trimming the engine to the ~4th 'notch' as indicated on the Yamaha screen. By that time, we are starting to prorpoise anyway. The engine is mounted in the middle bolt hole. Never cavitation otherwise.
Rob