View Full Version : 23T porpoiseing

native son
09-08-2011, 09:41 AM
Have a 23 T, 250 HP with 15 1/4 X 19 prop. Since I got the boat, would not plane without tabs, I have been content with this set up, but now I'm wondering if the motor is too low or maybe proped wrong. This set up came from BW, nothing changed. motor sits very low in the water at rest, I'm thinking motor should be higher?? motor sits inward on the bracket, seems unlike others that I have noticed, although I'm not mechanical, I feel that the boat should perform much better at start and not porpoise, even in calm water. Im at a point where I need some help and really dont know where to start, any suggestions would be much appreciated, there is a vacant hole to allow motor to be raised, am I on the right track or what should my next step be??? I have heard of wedges, raising the motor and changing props!!!! before I do any or none of the above, what do you think my first try should be. thanks for any advise.

09-08-2011, 05:15 PM
I am going to start this by saying I am NO Pro. I have a 2350 and had a 250 HPDI on it and was running about the same prop you are. My engine was mounted in the bottom hole, but BW has moved the brackets up on the newer engines so no good way to know if that is the same. Your best bet is to get it up on plane and walk back and take a look at where the Cavitaion plate is in the water when your cruising. It should be visable and not be barried under the water. Exact location is beyond my knowledge but I belive the cavitation plate should be just on the surface of the water.
In my past experience if your porpoising your engine is trimmed up too high. The no plane without tabs makes me belive that as well. IF your engine is tipped up too much then it won't let the bow fall, it is working to hard to raise the bow for you. If your planing with the tabs down it also makes me belive your engine is trimmed up too far, this would lead to a very innefficient run as well. Basically you have 2 forces fighting each other, for no real good reason.
I would check and make sure the engine does trim down all the way, then check the water level on your cav plate when running.
I have a 300 Suzuki on mine now and am still playing the prop games, but I know if I trim it up too far it starts to porpoise, I just trim it down a touch and it stops.
Where are you located, if your near maybe we can take a look at each others boats and figure it out. I am in Port ST Lucie. Mine isn't the 23t, but the hull is the same.

11-21-2011, 08:40 AM
How do you like the 23t ? What kind of #'s are you getting w/250 ? I want to see a 23t in person, hard finding somebody w/one.