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Sea Rider

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Which of the two pics is the "usual procedure" before bolting the motor on transom to dial for the AV plate to sit closer to the boat's bottom ?
 

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Faztbullet

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You use procedure in pic #2...the 3" means nothing as a splash deflector. That boat has been running fine as NO cavitation burns on prop an correct prop for that height, Bury that prop and efficiency goes down as designed to run partially surfaced..
 

WesNewell

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It doesn't matter which one you use.as long as you use the side of the sick touching the av plate there won't be more than ~1/8" difference in the 2.
 

Sea Rider

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So by simply watching a pic shot paralell to the AV plate, with prop showing no cavitation burns whatsoever which is signal of excellence prop work, would you say that the set-up current install dials the best water performance ever ? or will be much better to lower the motor a bit till the AV plate sits is even with the boat's bottom ?

Happy Boating
 

Sea Rider

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Going back to the famous AV plate set even, parallel to the boat's bottom everyone swears by, would you say that these two motor set-up examples are extremely well matched and you'll be pleased with such installs along an outstanding water performance ? One is a Yamaha 85 HP and the other is a Etec 60 HP, both being bolt on motors....

Happy Boating
 

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WesNewell

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Going back to the famous AV plate set even, parallel to the boat's bottom everyone swears by, would you say that these two motor set-up examples are extremely well matched and you'll be pleased with such installs along an outstanding water performance ? One is a Yamaha 85 HP and the other is a Etec 60 HP, both being bolt on motors....

Happy Boating

What makes you think everybody swears by it? I sure as heck don't. Each situation is different. Different hull types make placement different. Even individual uses of the same setup may need to be different. I would agree that aligned with the AV plate is a good place to start. The photos are basically meaningless without knowing what the owner is trying to accomplish. I would say whoever mounted those engines did so at a conservative height that would provide decent speed and handling.Want more speed performance, mount them 1-3" higher. Maybe a little lower would provide better handling in turns. All depends on what the owner wants. Could be as much as 4" difference on the same setup depending on that.
 

Faztbullet

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This is from the BRP rigging manual for 40/50/60 E-tec motors up to 2015. You constantly state that this is not in manuals but it is. You need to try and press your misinterpretations on the engineers and manufacturers of these motors that they are doing it wrong. The Tohatsu motors are different as they mount lower do to water intake but other brands do not fall into your opinionated set-ups. Yes both motor is pic's are set up well....Read the below slowly and carefully....
 

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Sea Rider

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Before going any further into the AV plate being over, even, under whichever. The 3 previous posted pics corresponds to 3 different HP motors powering 3 different hulls, question : would you say that the water flow will cross around the AV plate height when at full wot ? state your point . The 3 owners wanted supreme water performance "under all water conditions" which for you is what ?

If you think that Tohatsu it's the only OB brand that manufacturers Tall Plates Gap/Clamp Screw Motors ? Put your reading glasses and have a look....

Tall Plates Gap Motors.JPG

Hey WN I asked from you 2 issues which were : if you went for your Merc 60 HP motor parameters which state 25 mm (1 ") between AV plate and boat's bottom and at which lower leg height is water flow visually passing by ? If you want to have a neat tech conversation with me don't evade the question.....

Happy Boating
 

Faztbullet

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That top plate is a SPLASH DEFLECTOR and that is its only purpose!!! It has no bearing on where motor height should be!!
Here is mounting for Yammy 30 from the manual..
yam1.JPG
 
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WesNewell

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Sr, i think my previous post presents my stance on this very clearly. I did not take photos of the water flow of my boats setup and I've posted pictures of how it is setup now (mounted as high as it will go on my boat). I also posted a link that goes over the whole process of changing the engine mount height and prop changes and results. I will not duplicate it.
 

Sea Rider

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Answering your post. Nope the upper plate was not meant as a step ladder for any boater to climb from behind the motor which seems to be your concern about such ornament useless plate...

The upper plate which is a water deflector plate it's of "extreme importance" with 2 noticeable visual consequences that definitely won't go unnoticed...check pics !!

1-It it were non existing water flow at speed will climb through the front lower leg section and bang against the lower motor portion and divert back out transom, at speed so much water will be diverted that will slow the combo down due to excessive unwanted lower leg drag. Pic 1

2-With current upper plate, if the water flow at speed crosses over the upper plate the motor will achieve an excessive water splash side or over transom, to cure that will need to raise 1-2 notches the bolt on motor and shim or modified the transom height by means of wooden shims along a final fiberglass re work for an eye catching looking. Can anyone imagine the excessive fuel consumption and lower leg's excessive water drag such motor/transom mismatches accounts for as seen in Pic 1 & 2...

WN if you don't post pics, videos about what's going on at your lower leg to enlighten the on line audience, we have nothing to tech discuss...If the motor height at which you have install it pleases you, who am I to state the contrary...

No Motor Owner's Manual that have read and I've read all states that the flow needs to cross under the upper nor the lower plate, it's entirely up to each boater which type of performance wants to achieve while their combos rides at wot a particular water condition and location. Can both describe what's "Top Performance" for each one?

Hey Fazt, what's the point in posting a Yam 30 HP clamp motor if you don't own nor use one, your specialty are narrow plates gap bolt motor for racing, speeding which their particular own installs doesn't equate to clamp motors installs in the least.

Happy Boating
 

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Faztbullet

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No Motor Owner's Manual that have read and I've read all states that the flow needs to cross under the upper nor the lower plate,
I just showed you 2 that are from the manuals THAT CLEAR STATE to mount motor AV plate even or above bottom.
 

JimS123

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None of the pictures exhibited in this thread are correct. Pictures without data is a waste of time.

An outboard engine needs to be installed at every height available on the bracket. At each test point a complete performance curve needs to be tabulated under equal water conditions. Ventilation needs to be evaluated on tight turns. The proper engine height will be determined by the data. A deep deep V hull may have an optimum height that is different from a flat bottom or even a rubber boat.

Engine height is a process, not an I know better than you procedure.

If you have a little boat with a little engine that has clamps and a single hole for a securing bolt, then it needs to be mounted tight down on the transom and you need to forgetaboutit. Why? Because for that little guy any improvements won't amount to a hillofbeans.

For my current 4 boats, two have AV plates 2-3" below the keel (clamp on models), one has it 2" above the keel and one is 3" above the keel. I'm happy with all of them.

Why do we keep arguing? How much splainin does everybody have to do?
 

Sea Rider

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Hey gents throttle down, drop down a heavy anchor and drink some cold ones and relax, don't lose the composure...

The bottom pics proves that the BS AV plate placed even with the boat's bottom won't make the water flow to cross right there as most if not all assumes or states that will. Usually will pass way above the AV plate height. Who are you trying to fool besides fooling yourselves when no one has visually checked that at wot....

These 3 pic examples are boats locally manufactured with a mold with whichever transom height the manufacturer wants to play with. All 3 were previously install flat ed flat on their respective transoms which achieved excessive prop aeration on slight chop, windy, open water, off coast conditions, owners were not content with their water performance. As count with a skilled fiberglass techie ended shaving down all 3 transoms, all bolts holes were redone, now all motors sits flat on their transom at a lower position while the water flow at full wot now skims right under the upper plate (bluish line) It's my personal and my boating friends taste as well or you have an issue with that too ? To each one their own particular install taste, period !!

MOD EDIT - Removed by the babysitter.

Happy Boating
 

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Faztbullet

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Please post the pics of the engines at the height you state since the transoms have been modified.....If you cannot produce them then this post is BS.
 

Sea Rider

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Please post the pics of the engines at the height you state since the transoms have been modified.....If you cannot produce them then this post is BS.

The 3 motors shown at post 15 have their swivel brackets set flat even on their respective boat's transoms after their respective transom height modifications. Pic 1 corresponds to the Yam 85 combo seen on pic 2. On all 3 combos the water flow now skims right under the upper plate at wot which is the best lower leg setting to achieve top "all water conditions performance" which works best for me and my boating mates. It's a personal choice/setting as no motor manufacturer states at which lower leg plate must the water flow pass at wot, the final install it's entirely up to you....

If you are the top motor installer in anything that floats, answer this simple tech question : In all 3 cases, why isn't the hardened, unobstructed water flow passing at wot around the AV plate ? which for you guys is where the motor achieves the top water performance which for me doesn't say much as there's a hidden issue to state so.

NW join the tech conversation...

Happy Boating
 
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