Cavitation Plate location relative to hull

coldpizza

GreatGrady Captain
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Location
Los Angeles, CA
Model
Gulfstream
I was looking at the location of the cavitation plates on the (2) 200hp outboards on my Gulfstream. I am wondering where the cavitation plates should be relative to the hull. In other words, should the cavitation plates be above or below the hull when motors trimmed down. The outboards are 2019 200h Yamaha's set on the top bolt hole on the grady bracket. There is an option to lower the motor to the bottom bolt hole which looks like it would lower the motor about 2". Thanks in advance. Len
20211115_103312 red.jpg 20211115_103329 red.jpg 20211115_103407 red.jpg Inked20211115_103312 red_LI red.jpg
 
Then "anti-ventilation" plates should be roughly 1" higher than the hull for every 1' setback when trimmed parallel with hull. Can't tell from those pics - put a straight edge on the hull.
 
On plane, at cruise with the motors trimmed perpendicular to the water. The water should pass above the highest water pickup point on the lower unit but below the anti-ventilation plate. This video may be helpful
 
Then "anti-ventilation" plates should be roughly 1" higher than the hull for every 1' setback when trimmed parallel with hull. Can't tell from those pics - put a straight edge on the hull.
Thanks, I appreciate the info. I'll have to put a straight edge on the hull. The GW bracket pushes the outboard 24" from the transom. So should be about 2" higher. Is that based on the portion of the hull directly forward of where the outboard is?
 
On plane, at cruise with the motors trimmed perpendicular to the water. The water should pass above the highest water pickup point on the lower unit but below the anti-ventilation plate. This video may be helpful
Thank you. I will check out the video.
 
Thanks, I appreciate the info. I'll have to put a straight edge on the hull. The GW bracket pushes the outboard 24" from the transom. So should be about 2" higher. Is that based on the portion of the hull directly forward of where the outboard is?
It's on the "real" hull bottom - where the water touches.
 
:rolleyes:give up Dennis, even the OEM manuals say "anti-cavitation":confused:
I know, but the ones that say that are wrong. They are two entirely different things. Just 'cause it's printed in some destruction manual don't make it right!

And... I know you're just poking at me in good natured fun :)
 
I know, but the ones that say that are wrong. They are two entirely different things. Just 'cause it's printed in some destruction manual don't make it right!

And... I know you're just poking at me in good natured fun :)
we all have pet peeves.
If people would use than when comparing things rather than then and use then rather than than when refering to time, then they would be using the correct word.

"Than" seems to be have lost its use by everyone. I read a local fishing magazine that never used "than" in 20 years.:mad:
 
Then, than, further, farther, lesser, fewer and a myriad of other often misused words. Listing to the local newscasters can be painful for me.
Then there is the Oxford comma issue:)

Finally, my biggest pet peeve is the double negative!
"I didn't tell no lies" Oy!!!
OK, back to boating...
 
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Then, than, further, farther, lesser, fewer and a myriad of other often misused words. Listing to the local newscasters can be painful for me.
Then there is the Oxford comma issue:)

Finally, my biggest pet peeve is the double negative!
"I didn't tell no lies" Oy!!!
OK, back to boating...
hehehe "a myriad of" o_O


apologies to the OP for topic drift.
 
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we all have pet peeves.
If people would use than when comparing things rather than then and use then rather than than when refering to time, then they would be using the correct word.

"Than" seems to be have lost its use by everyone. I read a local fishing magazine that never used "than" in 20 years.:mad:
Ha! That's another good one! :)