vertical water spray from motor

[Keywest18]

Ill start off by saying my boat had a 20" transom and icut it down to 17" for my short shaft .with ot like that ot sits about 1/4" above the bottom of the boat. I ran it like that and no matter how I trimmed it I got vertical spray coming from both sides of the motor. I raised it to where its about 3/4" above the bottom and I got less spray and it ran fine but still sprayed equal amounts on both sides. Raised it to about an inch above the bottom of the boat and it ran ok on the second notch I can tell it was running a lottle higher rpm but nothin serious. On the the third trim setting I couldnt go past half throttle before it was over revving.so far it ran best about 1/2" above it I got 26mph but I still got spray.i dont wanna lift it anymore I even dropped it back to about 1/2" above the bottom cause it seems to run good there and ikno I have good water pressure.anybody have anyodea what could be causing this? Heres a picture of how it is,now

[flounder_smacker]

do you have hydraulic trim?

[Keywest18]

Negative....

[toodeep]

need a jack plate and go up with the motor. the higher you go the less spray you will have. you may need to have some cup added to go higher and not cavitate.

[fishfighter]

Originally Posted by toodeep

need a jack plate and go up with the motor. the higher you go the less spray you will have. you may need to have some cup added to go higher and not cavitate.

what he said ^ sounds like you need to add some more cup to your prop

[weedeater]

what size boat and motor are you trying to set up

[Marshrat]

For the best performance you need to set the cavitation plate above the bottom of the boat by about 1/2" - 3/4" with the motor level. When running your motor, if you don't have power T&T, should be about level up and down.

Looking at your picture (which could be the angle the picture was taken from), it looks like the motor is trimmed down too much which would cause spray.



Warren

[CajunChristian]

The rig needs to be properly set up. By that, the motor needs to run about 3 degrees positive trim at WOT with your normal load. That can be accomplished several ways. Once the rig is set up to run the proper trim angle, then start raising the engine till it blows out, then drop it 1/2".
D

[Keywest18]

Its a welded 1648 the motor is an 86 25HP Johnson with a 10x13 prop ill take some pictures in a few of howci run it trimmed. I had the motor trimmed down to get a better idea of how far above the bottom it was. How much does adding cup to a prop cost amd,can anyone in lale Charles do it?

[Top Dawg]

Originally Posted by CajunChristian

The rig needs to be properly set up. By that, the motor needs to run about 3 degrees positive trim at WOT with your normal load. That can be accomplished several ways. Once the rig is set up to run the proper trim angle, then start raising the engine till it blows out, then drop it 1/2".
D

^^^listen to this man.

[weedeater]

Originally Posted by Top Dawg

^^^listen to this man.

I will agree with this but I will also say that speed wise you probably close to max because that's a heavy boat with small motor but if it gets to the fishing hole it works. if you need prop work go to or ship it to Coastal Prop in Bridge City, TX or you can use Prop Shop in Lafayette but don't use anyone in ake Charles unless cajunchristian tells you a place, it sounds like motor is to low and you just need a jackplate.

[Keywest18]

The speed is fine. The motor planes it out fine and runs great.ive heard stories about people getting spray over the Cowling. Mine doesnt even come up past the transom its just when looking back I can see it.my anticavtitalion/ventilation plate is right above the water when cruising or WOT I.m guessing its not angled right but again this isnt my area

[weedeater]

Originally Posted by thegr8cody

The speed is fine. The motor planes it out fine and runs great.ive heard stories about people getting spray over the Cowling. Mine doesnt even come up past the transom its just when looking back I can see it.my anticavtitalion/ventilation plate is right above the water when cruising or WOT I.m guessing its not angled right but again this isnt my area

That sounds pretty good, maybe you have something on boat causing spray..... my transducer would do that on my old boat

[Keywest18]

Ive heard that but I dont have a transducer on mine. I do have a plug siliconed in from the outside its plugging the bilge for the livewells but thats off to the side I can definitely tell this is from the motor.

[Keywest18]

Not sure if these will help at all but I took some pics. first one is on the forth trim setting

Then third setting

Now second

Third trim setting

Fourth setting

Not sure if these will help at all but this is what im working with.then just for fun a shot of the entire rig

[Bluechip]

I still don't have an answer but thanks for the pics. I have been following this thread to see the outcome.

Goodluck!!!

[Top Dawg]

Jackplate. And do like Cajun Christian told me. Weld a piece of aluminum on bottom of jackplate to stop the spray.

[weedeater]

that's a different looking boat, what model boat is that?

[Keywest18]

Its a 95' fisher. Not sure of the model but its 1648