Yamaha90 optimal height?

Рет қаралды 919,545

15 жыл бұрын

Galia 515 bowrider & Yamaha 90 2-stroke optimal height testing.
3rd hole seems to be the best with original 17" aluminium prop, but 4rd hole is also strong alternative - but only with steel prop.
Btw. when it comes to rpms, i have a doubt about my tachometer: 17" Ballistic prop + 5100 rpm + 34,8 knots + gear ratio 13:26 = only 2,5% calculative slip ... ?
continuouswave.com/cgi-bin/pro...
I quess the real rpms are appr. 5300 - 5400.
A good dialog about engine height (with steel props):
www.veradoclub.com/smf/index.p...
I think my boat won't go faster than 35 knots with 90hp. I need more horsepower (boat maximum is 150 hp) - or lighter boat ;) On the other hand, with normal cruising speed (28knots) Yamaha 90 hp is pretty quiet and economical.

Пікірлер: 86

@IanYouTubian 14 жыл бұрын

This has been the best information i have received today! Thanks for the video. I was getting such nonsense information regarding the anti ventilation plate. This has been extremely helpful!

@flyingtigre1 9 жыл бұрын

yes i agree…. great information on u tube to know what of an idea to perform at optimum out board motor height. thank you Salty Seaman.

@julunted024 12 жыл бұрын

@s6675 the plate is designed to reduce ventilation occurrences. which is when the boat is on plane, and surface air reaches the propeller and reduces the load dramatically. can cause over-rev situation, and cavitation sometimes. but dont worry, everyone cant be correct all the time...

@canajaprimabi1267 11 жыл бұрын

complimenti per il motore!! viva i 2 tempi!!

@joeblowjohnny2297 11 ай бұрын

Remember ..... the higher you go with that cavity plate ? The less water pressure you have for the water impeller pump to work efficiently !

@gonefishing1939 4 жыл бұрын

I spent a bit of time doing the exact same things for my 40 2 stroke suzy on my 18ft lund alaskan. i made a few vids on it. the biggest differences i found was swapping to a stainless prop with 1 inch greater pitch and motor height. also weight reduction. i went from around 26mph to 34.2mph after a few small upgrades. now im looking for a jackplate.

@ricoco750 12 жыл бұрын

thanks for sharing. very informative

@wynandvandermerwe2326 8 жыл бұрын

Help i cant turn off my 90aeto. recently changed the ignition solenoid so im guessing ive done something wrong there. switch and cut off was all working fine before

@socore4659 5 жыл бұрын

once you get it up on plane you just trim the motor up a bit and play with the bow height. That will get more boat out of the water and you'll go faster, so you should be able to pull RPMS. If you are going to hit a rough patch of water and or do a sharp turn, trim down first and get the bow in the water for better control. Looked like the engine was in the perfect spot on that 4th hole, once you trim it out you'll pull RPMs and probably get like 5 more knots i bet.

@jerrychf 8 жыл бұрын

Thanks for the video and the test, it really made help for me. But is that the 90hp had the height hole to adjust? My 115hp seem didn't have that thing ... or I miss it?

@smalldog221 12 жыл бұрын

Does it cavitate with the engine all the way up on the fourth hole in a tight turn?

@AB-80X 6 жыл бұрын

Two things. Get that anti ventilation plate 1½-2" above the keel, and get that horrible alu prop off it. Find something like a Mercury Laser II for that boat. Getting the engine height right and the proper prop, you'll see at least a 4-5 mph gain in your case, with better overall performance.

@mcplutt 5 жыл бұрын

Mercury Spitfire

@shipitoautomarinellc Жыл бұрын

great video

@83Roppie83 13 жыл бұрын

nice useful video !

@josman2001 11 жыл бұрын

Hi, I must see the cav plate with the trim neutral? or trim Up?

@carrysmith2008 10 жыл бұрын

what diameter and pitch is ur current propeller?

@julunted024 12 жыл бұрын

@s6675 actually, there is no such thing as an anti cavitation plate. it is very very common, and even proffesionals will call them cavitation plates, but they are truly anti-ventilation plates. its just semantics, so it doesnt really matter. but dont need to correct people, when you are wrong yourself.

@s6675 14 жыл бұрын

I got a 1994 pro 50, and on the 3rd hole on my boat it does 48 MPH with a 4 blade prop at 5500 RPM.

@searider9922 5 жыл бұрын

The best engine/ transom height match is the one achieved when water flow skims right under the small upper plate. Raise or lower engine accordingly to match that given height and by visual inspection check if you're already there. Trim must be set at neutral along a perfect deck weight distribution. Once there prop will achieve the best prop thrust as there's more water level for blades to grab better on water compared to flow skimming around AV plate area. Once correct engine/transom height matched has been achieved, you should go for a prop maximizayion to a usually less pitch prop whether aluminium or SS ones in order for engine to rev at least middle to max wot rpm range factory stated and as usually loaded.. This engine/traansom match works very well in most water situations such as flat calm, windy, choppy conditions and at close tight turns at speed, be my guest and check if for yourself....

@holdenbriggs729 2 жыл бұрын

you prolly dont care but does anybody know a method to log back into an Instagram account..? I was dumb forgot the account password. I would love any help you can give me

@ezrarhett285 2 жыл бұрын

@Holden Briggs Instablaster =)

@holdenbriggs729 2 жыл бұрын

@Ezra Rhett thanks so much for your reply. I got to the site on google and Im waiting for the hacking stuff atm. Seems to take a while so I will get back to you later with my results.

@holdenbriggs729 2 жыл бұрын

@Ezra Rhett it did the trick and I now got access to my account again. I'm so happy:D Thanks so much you saved my ass :D

@ezrarhett285 2 жыл бұрын

@Holden Briggs Happy to help :D

@ElectricDanielBoone 8 жыл бұрын

Check to see if it cavitates when you're turning at WOT.

@edwardabrahamiii3742 3 жыл бұрын

Put weight in the bow and itll fix your cavitation

@cajunfamily5227 4 жыл бұрын

what size prop ya running there

@JamesWright1955 6 жыл бұрын

someone at the marina suggested my motor is set to deep into the water.

@socore4659 5 жыл бұрын

i hope you smacked them right in their face...

@Ducktruckful 3 жыл бұрын

did you notice any over trim with motor raised? mine runs better raised but unable to trim up as far!

@jandelahoussaye9834 4 ай бұрын

Same as mine I can't trim motor up much before front starts bouncing

@jstorres486 4 ай бұрын

Do you do this with outboard fully trimmed down

@olegasvaltis406 5 жыл бұрын

Super

@johnechterhoff4791 10 жыл бұрын

Jack-Plate.

@lfino100 4 жыл бұрын

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@thebigmann25 11 жыл бұрын

You could get better bow lift by trimming up

@user-qu2wr3oi3n 6 жыл бұрын

احسنت

@tapmad 14 жыл бұрын

Love the vid. Now please spill some money for a hydraulic jack plate and run some tests.

@esasaarinen2423 3 жыл бұрын

and rip off your transom. never put jack plate if you have an offshore boat. set back especially kills transoms

@tapmad 3 жыл бұрын

@@esasaarinen2423 Noooo... You strengthen the transom to accommodate jacking plates or increased engine size. You might even increase floatation at the rear. Always get engineering advice before attempting boating upgrades.

@esasaarinen2423 3 жыл бұрын

@@tapmadI wouldn't use a jack plate if the boat sees heavy seas. Jack plate manufacturers will sell you a jack plate no matter what. Most boat manufacturers won't recommend one unless there is a need to run in shallow water in a skiff

@tapmad 3 жыл бұрын

@@esasaarinen2423 Nooooope.... Most manufacturers would not care, nor comment, because they build boats for the mass market, and jack plates are specialist equipment. They definitely work, and they are definitely safe in the ocean. In regard to ocean going boats, jacking plates are really handy for fine tuning an old ocean boat that has been converted from an inboard to an outboard. These boats were not build with cut down transoms. Common for boats from the 60s and 70s in the 20-30ft range. When doing this style of conversion, a pod is added to the transom of the boat. The pod sets the outboard back about 30 inch off the transom. So the pod is in fact just a great big jacking plate. However, because the pod is difficult to reposition, if the engine is changed, a jack plate helps get it in the best overall height. The advantage of a hydraulic jack plate is that the height can be changed to accommodate different loads. A fully fuelled 26ft boat, with 10 passengers and crew on board might be 2000 pounds heavier that an empty boat. They are also a great addition to a bass boat. But they are definitely a luxury or enthusiasts item. You can do 98percent of normal running without them - that's why manufacturers don't even bother mentioning them. It's that other 2 percent, that extra 2mph, that make them special.

@esasaarinen2423 3 жыл бұрын

@@tapmad I have added a jack plate to my nimbus nova it cracked the transom . I just bought a new scout they will void the warranty if I install a jack plate

@davidjessee7701 3 жыл бұрын

Looks to be about 3 or 4 inches too low..

@barry8458 Жыл бұрын

Flat out speed ..great !…cavitation..problems when choppy or rough conditions on turns …got a jack plate it’s all good..permanent mounting..not good idea…

@user-dw4yh1kx9p 4 жыл бұрын

Пусть покажет как на поворотах будет вести себя катер?

@Yanot32 3 жыл бұрын

Он не поворачивает, только вперёд !!! Если будут прохваты, повесит 120 ку ))

@brobaiter7903 6 жыл бұрын

if that boat came to you stock don't fuck with it if you want a high perform prop by one it's that simple

@VS-os1lh 6 жыл бұрын

умные ребята

@user-cg8se7se9n 6 жыл бұрын

V S умные по русски пишут )

@nobody46820 4 жыл бұрын

🙂👍🏻👏🏻👏🏻👏🏻

@Drunken_Hamster 10 ай бұрын

Go down a pitch and add a blade, THEN tell me how good it drives and lifts after that.

@user-jn4hh5fu2y 5 жыл бұрын

Да тут все понятно. Мотор 90 , ямаха. 😁

@Mad.Man.Marine 7 жыл бұрын

The thing is. Is that your under Erving the crap out of that 90. Those are meant to turn 5200-5500. At the rpm you are running at what I guessing is wot. You are way loaded up and that engine is going to toss a rod out pretty freaking quick.

@jacksmith8255 6 жыл бұрын

TheMadair not even close to stressing that motor, 3cylinder 2 Stroke Yamaha would pull 6000rpm all day.

@coolkid6364 4 жыл бұрын

Umm the factory manual says 4500 to 5500 rpm wot rpm LMFAO shade tree mechanic idiot

@jezza1999 11 жыл бұрын

That engine is way to high. your opening yourself up for a whole heap of issues. like. prop burn ( micro bubles caused by cavitation burning off the ally) the manual recomends the engine be .5 to 1 inch below the bottom of the hull. My new engine is just in like with the bottom of the hull and we are getting issues like prop burn, caviataion, prop slip due to cavitaion. cavitating in turns. check your manual.

@mcplutt 5 жыл бұрын

You probably mean prop ventilation. Cavitation isn't the same.

@craigkaschan4822 5 жыл бұрын

That anti cavitation plate should be below water line so you can adjust your trim. That’s where I get speed and fuel economy. Please anyone correct me if I’m wrong. Safe boating 🇦🇺

@keithfredrickson9730 2 жыл бұрын

Your wrong

@mattwaters6987 Жыл бұрын

@@keithfredrickson9730 my manual says anti cavitation plate should be no more than 1" below the keel line. Just saying... (2018 Mercury 9.9)

@jezza1999 11 жыл бұрын

Not so. its defo too high. read the manual ;-) If your prop was a surface breaking prop then fine but its not. dropped our down a whole and its perfect. no slip, no cavitaion no nasties with prop.