Rudder doesn't want to turn much to right under hard power?

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rost495
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Rudder doesn't want to turn much to right under hard power?

Post by rost495 » Mon Jan 30, 2012 12:31 pm

Boat doesn't want to steer to the right with heavy load and under power???

My rudder stick moves freely from side to side with the motor not running, and will move pretty easy with a bit of throttle, say 2500 to 3000 rpms or so, just on plane and cruising, but I"ve noticed with a full load of folks in the boat, and under close to max throttle or in high wind, it feels like you'd break the rudder control stick(done that once and welded it back and it scares me now to push too hard) if you would get it to move much.

IMHO from glancing at it, it seems like I can get about one hour of movement on a clock face under h ard power, let off a bit to plane only speed and I can get the full movement....

What do I look for?

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Re: Rudder doesn't want to turn much to right under hard pow

Post by dshaw94 » Mon Jan 30, 2012 12:57 pm

I bet you have a bad bushing or something in your rudder mounting is lose and when you apply a lot of wind load to the rudders one or possibly both (i doubt both) are binding when you try to turn right. If you haven't already, check the rudder mounts and all your steering linkage for slop. Try to apply rearward force to all the components similar to that of the prop wash in an attempt to recreate the bind. If you are using telflex or similar steering cable you may also be experiencing bind at the rear of the cable. It may not bind until the additional load is applied. Good Luck :thumbleft:
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rost495
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Re: Rudder doesn't want to turn much to right under hard pow

Post by rost495 » Mon Jan 30, 2012 2:54 pm

Just pulled and replaced bushings, lubed it all up a bit, and checked the cable last spring and its been on the water maybe 5-6 times since, thats why I'm really wondering whats going on....

Was thinking more it might be something with the trailing edge of the boat needing to be bent some or the trim tabs on the rudder needing adjustment of both of which i know almost nothing about...

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Re: Rudder doesn't want to turn much to right under hard pow

Post by AirRanger » Mon Jan 30, 2012 6:27 pm

If your rudders have tabs, they can be adjusted (bent) to negate the force required to move them under a load. Those small tabs make a big difference.
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Re: Rudder doesn't want to turn much to right under hard pow

Post by poornotlazy » Mon Jan 30, 2012 8:35 pm

How long is your prop? It sounds like your rudders may be too close to each other.
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Re: Rudder doesn't want to turn much to right under hard pow

Post by TIGO541 » Mon Jan 30, 2012 10:06 pm

Mine were doing the same thing. Come to find out, the rudders were only a 1/4inch from being straight with each other. I adjusted them so they were same measurement front and back and no more problems. Hope this helps.
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Re: Rudder doesn't want to turn much to right under hard pow

Post by rost495 » Tue Jan 31, 2012 11:26 am

Seems like 78 inch prop.. I"m guessing 12 inches from rudders.

Can and will check of rudders are in line with each other or not.

Which way to bend tabs and how much makes a difference?

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Re: Rudder doesn't want to turn much to right under hard pow

Post by PeaRiverOpossum » Tue Jan 31, 2012 12:22 pm

Im pretty sure that the rudders should be slightly "toed in" like the front tires on a truck. They should not be parallel. Just heard this the other day from an old timer that frequents here.

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Re: Rudder doesn't want to turn much to right under hard pow

Post by rost495 » Tue Jan 31, 2012 12:28 pm

toed in in the front or back? IE closer front edge closest to prop or back trailing edge, and how much difference...

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Re: Rudder doesn't want to turn much to right under hard pow

Post by PeaRiverOpossum » Tue Jan 31, 2012 12:30 pm

rost495 wrote:toed in in the front or back? IE closer front edge closest to prop or back trailing edge, and how much difference...
the trailing edges are supposed to be closer than the front...call chuck and get him to explain it if he has time. Im not sure how much and dont want to give bad info like some do.

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Re: Rudder doesn't want to turn much to right under hard pow

Post by glades cat » Tue Jan 31, 2012 1:25 pm

Is there a pic of the boat?
If you have a reduction drive and right swing prop, the lower from center your rudders are, the more the bottom prop wash pushes on the right side...keeping you from turning under power.
Also, the bigger and slower props have more angle and push more air sideways, especially at static or slow speeds.
You may have to raise the rudders, or move the rudder pivot point aft, to counter the side load.

Just a thought.
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Re: Rudder doesn't want to turn much to right under hard pow

Post by rost495 » Tue Jan 31, 2012 2:31 pm

What picture you want possibly? Belt drive.

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Re: Rudder doesn't want to turn much to right under hard pow

Post by rost495 » Tue Jan 31, 2012 2:32 pm

Image

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Re: Rudder doesn't want to turn much to right under hard pow

Post by poornotlazy » Tue Jan 31, 2012 11:39 pm

Your rudders should be about 30" apart for a 79" prop.
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Re: Rudder doesn't want to turn much to right under hard pow

Post by air-roberts » Wed Feb 01, 2012 4:37 am

thats right 30" for a long prop and at min 6" away from prop and toed in 1/8 to 1/4 in at the back. and make sure that each rudder moves independently easy and then connect bar and do the same . did you hang rudders with a plum-bob? and check your cable. if all passes you good to go. oh and i forgot on rudder stick from pivot point who long is that it should be 12" to 13" and the rudder side 5" to 6"
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Re: Rudder doesn't want to turn much to right under hard pow

Post by Steppinoutdoors » Sat Feb 02, 2013 1:16 am

Ok guys, I am having the same problem with my newly aquired boat. I can turn very easy to the left, but the right takes everything I got. I can let off the gas and turn the rudders sharp right and once I get back into the gas I cant hold it. On top of that, Glades Cat mentioned something that is also happening. at idle I can turn to the right and when I start giving it some gas it almost drags the left rear corner of hull under water. I can't take off doing a right turn!! It feels like the left corner is being pushed down when I try to give it gas. This is a 79" Whirlwind triple blade Prop on 502cui with a gear reduction 2:09.1 ratio. Any thoughts other than what has already been mentioned? I am second owner and I am pretty sure the rudder tabs are wrong. They are both bent to the left (looking from the back of the boat). The boat doesnt pull to any one side when on plane and gas pedal to the floor. ANY help would be GREATLY appreciated!
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Re: Rudder doesn't want to turn much to right under hard pow

Post by John Fenner » Sat Feb 02, 2013 2:52 am

You folks kill me with your toe in and toe out, both rudders shall be equal front to rear and at most 28" apart.
I never finish anyth,,,.

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Re: Rudder doesn't want to turn much to right under hard pow

Post by scottymartin » Wed Feb 06, 2013 7:22 am

:scratch: Trying to remember, from years ago... a AV engineer told me... I think, but not gospel.
Take your prop length, divide into thirds... the rudders, should set at the two mid points,
for your sweet spots. :cheers:

Error to the center, not main air flow.

:dontknow: Now, if you keep changing props, well that is another story. :dontknow:
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Re: Rudder doesn't want to turn much to right under hard pow

Post by cntry141iq » Wed Feb 06, 2013 2:02 pm

1/2 the prop minus 10 usually works pretty well

added ....... some say minus 12 .. either way works .. keep them back usually around 6 to 8 and 1/3 of the height above center of prop if my brain aint getting froggy ..
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Re: Rudder doesn't want to turn much to right under hard pow

Post by Rich Andrews » Wed Feb 06, 2013 3:52 pm

Nascar rudders..
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Re: Rudder doesn't want to turn much to right under hard pow

Post by LIL Maddog » Wed Feb 06, 2013 4:41 pm

John Fenner wrote:You folks kill me with your toe in and toe out, both rudders shall be equal front to rear
X2 It is not often i agree with you but on this i completely agree. All this toe in or out on the rudders is complete BS.
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Re: Rudder doesn't want to turn much to right under hard pow

Post by cntry141iq » Wed Feb 06, 2013 4:46 pm

you mean you cant funnel the airflow and get more power .. LOL that is what I was told one time .. really ???

it might help a set of poorly hung rudders track the boat straighter .. but then again a poorly hung set may just break the rods .. or was that a bad carb tune ?? I get so confused anymore ... I gotta go get me some reef frogs .. averaging bout 9 pound seach this time of year I hear
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Re: Rudder doesn't want to turn much to right under hard pow

Post by LIL Maddog » Wed Feb 06, 2013 4:49 pm

cntry141iq wrote:you mean you cant funnel the airflow and get more power .. LOL that is what I was told one time .. really ???

it might help a set of poorly hung rudders track the boat straighter .. but then again a poorly hung set may just break the rods .. or was that a bad carb tune ?? I get so confused anymore ... I gotta go get me some reef frogs .. averaging bout 9 pound seach this time of year I hear
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Re: Rudder doesn't want to turn much to right under hard pow

Post by SyS3d1t » Wed Feb 06, 2013 4:59 pm

Funny stuff cntry!!
Mine was also hard to steer right moved them 2 inches back and got them plum they was not hung plum helped out a lot steers easy both ways now but is pulling to the left so check em for plum
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Re: Rudder doesn't want to turn much to right under hard pow

Post by cntry141iq » Wed Feb 06, 2013 5:11 pm

if it is just pullin a little bit .. that can be fixed with the tabs .. that can come from the spin of the air pushin on one side of the rudders harde rthan the other .. a car motor boat usually pulls opposite a ac boat because of rotation of prop being different.

Hope you didnt get mad .. the carb stick was meant as a joke ..
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