boats leans badly ..from new etec

grub_ba76

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Jan 9, 2009
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Re: boats leans badly ..from new etec

ahhh ok ty.....i dont think the skeg is bent or anything.....its a brand new engine with 6 hours on it.....has never hit no objects.....hasnt even got a scratch on the skeg......or could it be twisted ect from new?.....the book and mechincs recomend the anti cavatation plate sits 1 inch and no more below bottom of boat........as i said last motor cav plate was level with bottom of boat and was dangers and performed badly.....yeah it was ok on flat water but when ur in 2 to 5 metre swells and riding waves it was dangers and wrong.....every time u go over a wave it would cavatate cause the prop was comin out of water when the nose was droping over wave.......i know that speed boats set with the cav plate level with bottom of boat went faster as there was less drag.....but not on a fishing boat that is only used in ocean swells.......thanks for info........i did learn somthing......do yas know if it is prop torque can it be fixed.....i from australia btw......and i dont understand what yas mean by ventalation.....from what im reading and learning its a anti ventalation plate(not a cavatation plate.does both jobs to me) to stop the prop getting air.....correct me if wrong ty graham.....
 

steelespike

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Re: boats leans badly ..from new etec

Ventilation is what happens when a prop loses its grip.Cavitation is a different animal.It usually occurs in the lowpressure areas of a prop
usually most evident by a roughness on the back of the blades. Severe cavitation can cause damage.You can't feel cavitation.As I under stand it leg length is in 5" increments so that shorter leg on the 35 would be 5" shorter
making it impossible to get low enough.I feel if the new motor was put at the same hole setting without trying the best setting the setup could be too low.
I'm not a prop expert but based on what you say the only difference is the prop.As I said some props give stern lift some bow.You might post in the prop forum see if they have suggestions for a prop that might help. Be sure to read the sticky for getting the most out of your question.
My point of trying the 135 prop if it phyically fits is we know it ran without leaning.If it fits and doesn't lean you know it is the new prop.If it still leans we know it is the setup.You could also try the basic aluminum factory prop
see what the results are.
 

grub_ba76

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Re: boats leans badly ..from new etec

ok thanks.....the 135 is long gone. it came with the stainless steel prop. didnt get the alloy one....will call shop see if he does....yeah i know they come in 5 inch ingrements..but the first gearbox was fine the replaced one was roughly 10 to 20 millametres shorter .i know doesent sound right but the last one was below bottom of boat and the replaced one was like 5 mill above bottom of boat....which caused it to do what it done...in the manual for my motors (suzuki)and my bros etec says it should be approx 1 inch below bottom of boat.....i have no clue what is right. i know that when my bros old boat motor was level with bottom of boat it was not working(no steering,sucking air and reving out) is there a right measerment or does it depend on boat...thanks graham
 

CaptRoob

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Dec 11, 2008
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Re: boats leans badly ..from new etec

this is a long shot but try taking a 6 to 8 foot(2 to 3 meters) straight edge. put the straight edge against the bottom of the boat from the transom forward. look to see if there is any spacing between the hull and the straight edge. if there is spacing between the straight edge and bottom of the boat your boat has hook if you can rock the straight edge like a seesaw then you have rocker. if any of these two conditions are the problem then it will be more extreme the faster you go.

some boats have these designed into them also so you may want to check with the manufacturer to see if they built in hook or rocker to the boat. if they didn't and it has either or was not done correctly on both sides of the vee/keel then that may be your problem. otherwise i would look at the prop or motor mounting to make sure it is level.

if the anti cavitation plate is not level the boat would follow the angle that the plate is on the faster it goes and would be more extreme if you had a doel-fin or stingray on the plate.

if all else fails put on the biggest trim tabs recommended for your size boat and learn to use them. in my opinion anything over 20' or 6.5 meters trim tabs is a must. your running conditions from one day to the next are very seldom the same and trim tabs help to level the boat for uneven loads and bad riding characteristics. they also help increase cruise fuel efficiency and will keep you on plane at a lower speed than without them.


hope this helps
 

CaptRoob

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Re: boats leans badly ..from new etec

one more note. if your boat has a skid pad of some sort make sure that it is straight also with the straight edge.
 

steelespike

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Re: boats leans badly ..from new etec

There isn't a "right measurement" nor is there one prop only for a specific application.Different motors and differrent props will run at different heights.
If the shape of the bottom or added accessories disturbs the water the motor may vent easier.If the prop is a BRP prop it should be best for the motor but perhaps not best for the application.Again not a prop expert but there are props that resist venting better than others even though similar designs.There is no doubt a need to run the motor deeper for your boating
More and more I think while we may be able to raise the motor by playing with the prop I don't think enough to solve your leaning problem.
Post your Q in the prop forum I really think that if we are going to solve this it may be with a prop.If you run the boat at the 135s speed does it lean.Are there any similar boats you could consult with?
 

grub_ba76

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Re: boats leans badly ..from new etec

thank u capt...good info....triming up or down does make the boat perform diffrent.as it would(lifts nose or sinks nose) but doesnt make no diffrent on leaning. havnt checked with straight edge but im sure its a rocker.. im takin ur info in but dont forget old motor didnt do....that was gonna be my next question. trim tabs on boat. i understand how they work but never had experince with them.....as u said prop must be the problem....and yes most bigger boats i see have trim tabs on them.....so is this how it would work....the side its leaning to would be trimed down in the water more then other side? its a deep v at front of boat but is close to flat at back(its about 2 inch v from being flat)....again thanks all for info. it will save us a lot of mucking around....graham
 

grub_ba76

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Re: boats leans badly ..from new etec

thanks steel i will try prop section.....it only gos about 5 to 8 kmph faster then the 135hp....my dad has the exact same boat only diffrence is dads has no build in live bait tank(which is in middle of boat on my bros) dads is a 135. lots of pro fishermen have these boats with much bigger hp(200hp and twin 200hp)and ones ive asked look at me funny and never heard of it happening...and say not with these boats there one of the best performing ocean boats around(there words noy myn) so as yas are saying it must be the prop its an evenrude factory stainless prop. its one of those flash looking props it has the evevrude simble on it(cant remember the 3 letters)...thanks again...i knew a little a bout this now i know more.....good people ty graham
 

steelespike

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Re: boats leans badly ..from new etec

Not meaning to point any fingers but if they pulled the boat to fit the motor
perhaps it met with an accident damaging the bottom.Perhaps the dealer didn't even realize anything happened.Wouldn't take much to cause a problem.Also wouldn't hurt to talk to the builder to see if any differences in construction.Sure is interesting that to this point no one has had a similar problem.Are there others out there running Etecs?
 
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