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help needed engine height

RReaume

RReaume

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2014 2550 RCB ESP Yamaha F300 X A
Right now my engine is in the 2nd hole.

The picture shows where the water line is at cruise speed trimmed 1/2-3/4. Should I raise the motor up one more hole? Mine has the intake just below the water line shown in the picture will this be an issue if I raise it up?

The dealer tells me I will get blow out if the engine is raised. Though everything I read is to have the anti cavitation plat at water level.

Need your input.

Thanks
Roy
 
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I don't usually refer to other discussion boards, but this is an excellent thread addressing this topic, good pictures.

http://www.veradoclub.com/smf/index.php?topic=137.0

You should be able to see the cav plate when it's running level. That plate is about 1.5" below the water line mark on your drawing.
 
Roy,

There are a few videos out there and I think even some by Yamaha that show where the cavitation plate should be when on plane.  This video gives a good demonstration of what the cavitation plate should look like - not buried in the water, but still getting "splashed".

If that is where the water is when you are on plane, then it needs to be moved up for sure according to all the outboard websites that I have read.  Good luck and let us know how it turns out.
 
What about the intake holes above the anti cavitation plate.  If the plate is flush with the water will there be enough water going through the intake.
 
I have a question on this, hope you don't mind me tagging along to your thread. I've yet to determine if mine is in the right hole or not, but if I did want to raise my engine a notch or two, is it possible to do it myself or do I need the dealer to do it? Looks like I could just take out the top two bolts then loosen the lower ones to slide it up. The challenge seems to be lifting the ~375 pound engine up an inch or two but maybe with enough muscle it would be doable? I have a feeling mine is too low for how much weight I usually have on the boat but won't know for sure until I have it out again. 
 
Water intakes are on the sides below the plate.
 
My dealer used a fork lift to move holes (heavy motor would not want to try and lift it by hand)
 
I would go up another hole, try it out and if it doesn't work, drop it down. It won't hurt to try.

Nick, you could use a floor jack and a block of wood under the skeg.
 
cwag911 said:
Nick, you could use a floor jack and a block of wood under the skeg.
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That's a great idea, Carl. I was thinking about backing it under a tree and using a come along and tow straps but that might be easier than finding the right tree. :)
 
just got off the phone with Yamaha and they stated the 3 slots above the anti cavatation plate are exhaust ports so I think I will have the dealer raise it up 1 more hole and see how it performs
 
RReaume said:
just got off the phone with Yamaha and they stated the 3 slots above the anti cavatation plate are exhaust ports so I think I will have the dealer raise it up 1 more hole and see how it performs
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Sorry, yes, I believe they're exhaust relief ports for better hole shot. Just make sure you have constant water pressure as motor position is raised and trimmed up.
 
We have a 2013  2550 GBR with a yamaha 225 with clean toons at wot 41/42 give or take at times but the cav plate is on top of the water your intake is fine at this point sounds to me you should be up a bit
 
Carl's suggestion is probably better than this one, but another option is to lower the tongue all the way down, then block the motor solid, then raise the tongue using the hand crank and front trailer wheel. Just another thought.
 
Ness3 said:
We have a 2013 2550 GBR with a yamaha 225 with clean toons at wot 41/42 give or take at times but the cav plate is on top of the water your intake is fine at this point sounds to me you should be up a bit
Click to expand...
Does your prop blow out in the turns or do you put the trim down when turning
 
My backup prop blows out unless I trim down all the way. It was a pain having to tune the trim constantly, especially pulling tubes. I'd rather have the motor a little low than wear out the power trim hydraulics.
 
previous prop salt water series 2 15.5 X 17 motor second hole 1/2 tank fuel 1 person 5600rpm 41-42 MPH. So I just ran the reliance 14.25 X 17 with the motor in second hole. 1/2 tank of fuel 1 person on board 6100 rpm 44mph. Than filled up the boat with fuel 6000 rpm 43-44 mph. I could tell with the reliance it would spin alot easier than the sws2. Though with the reliance prop compared to the salt water series 2 I lost mid range mph. Reliance 3000 rpm 14-15 mph. SWS2 15.5 X 17 3000 rpm 20-21 mph. They have a 15.25 X 15 prop I might try that will give me the mid range and increase the rpm'S (mid range is where I cruise so I would rather have higher top end here than at wot)
 
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