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Old 26 August 2013, 13:18   #1
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Too high?

Hi all,

I get alot of splashing either side of the leg at speed. It gets worse as you trim it in. I suspect this means the engines in mounted a bit high. You can see from the attached pic that it looks like water is being pushed up towards the lip above the cav plate and then outwards creating the splashing:



...and just to show what I mean about the lip, you can see it here about 2" above the cav plate:


Here's a video taken at the same time as the first pic. The engine is trimmed about neutral here:


Any opinions/advice?
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Old 26 August 2013, 18:07   #2
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Looking at that first picture, your engine is too low in fact hence the reason for all the water spray. I'd try going up a hole at a time till you get the best result.
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Old 27 August 2013, 03:02   #3
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We had exactly the same thing with our Searider, we lifted the engine 1 hole and although it reduced the spray the prop didn't have the same grip, it would cavitate in tight turns.

We lowered it again and lived with the spray.
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Old 27 August 2013, 12:23   #4
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Up you say? But that would bring the cooling water intake further out of the water? It already looks worryingly high to me compared to the waterline at speed. It's obviously pulling in water or the telltail would stop but I'm not sure I'd want it any higher.
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Old 27 August 2013, 12:39   #5
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The cavitation plate (the one just above the prop) wants to be almost level with the bottom of your hull when vertical. Water intakes are below it so unless it's extreme they should always be in the wet stuff.
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Old 27 August 2013, 12:44   #6
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Quote:
Originally Posted by paddlers View Post
The cavitation plate (the one just above the prop) wants to be almost level with the bottom of your hull when vertical. Water intakes are below it so unless it's extreme they should always be in the wet stuff.
Yes, I are muppet! Mixing up water intake grills with the the one just above the cav plate towards the rear. Dunno what they are but they damn sure arent where I put the muffs on!
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Old 27 August 2013, 12:46   #7
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That engine is way too high, lowered it untill water flow passes slightly under small upper deflector plate, that's with well trimmed engine to achieve boat and anticav plate riding near paralell to water level. It's the perfect engine transom height for good hole shot, inmaculate close turns at speed and overall good boating on all water conditions.

Happy Boating
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Old 27 August 2013, 15:49   #8
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The grates you are talking about are just exhaust relief ports. The plate above the cavitation plate is just a deflector the water should run just on the underneath of the cavitation plate when set right. I would definitely be lifting that engine without a doubt. It is just trial and error to get the best balance so you don't loose too much grip in tight turns but then how often are you doing high speed hard turns.
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Old 27 August 2013, 16:34   #9
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So it seems that the one thing we can all agree on is that it's too high.... or too low.

I'd need someone with a crane if i was going to raise (or lower) it so it'll probably need to stay as it is for now. If the opportunity presents itself I guess I'll need to experiment. Thanks for the input though guys.
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Old 27 August 2013, 16:49   #10
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Quote:
Originally Posted by Clamchowder View Post
I'd need someone with a crane if i was going to raise (or lower) it
No you don't, it's easy. Lower the jockey wheel, block up under the skeg with timber, remove the bolts through the holes in the transom bracket, loosen the ones in the slots just enough to allow the engine to move & wind the jockey wheel down until you move up a hole, simples
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