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pulls hard to the right

bondsman

bondsman

Well-known member
any suggestions would help my boat pulls hard to the right to the point if i let the stick go it would just do doughnuts.rudders seem to be in a good position, and even placed on the back just would like to know if any one has experianced this.nice and easy to drive when it was dd now i have to muscle it with the gearbox.the cage and riggin was built by ned at hoffmans so i do trust his work.
 
We had a chunk of fiberglass come loose one day.... it was a crappy repair done by the former owner. But the dang thing was like a fin in the water. It acted just as you describe.

Maybe check your hull bottom & polymer.

You probably already measured the rudders - distance at the front equals the distance at the back?

Boat float level in the water?

matt.
 
boat floats level,have steelflex on the bottom no problems there i can see.i have fiddled with the rudders a couple of times setting them up different to see if it would change.boat drove great when it was dd the only change when i went gearbox was a new cage, riggin moved 3inch foward, bigger prop and the same guy built the new cage.and also it pulls just as hard to the right when runnin the ground.
 
Since you seem to feel all of that is ok, I would get a plum-bob and drop from the center of the crank in the front of the engine to the center runner and then repeat on the prop hub.

I'm thinking you have a new engine stand since changing to a redrive. Simple to check anyway. In fact after assuring that, I would continue to check the prop tracking. It seems to me, at this point, it isn't going to be something visible or intuitive.

ON my old Cessna Skylane ya had to hold near full left rudder on part of the takeoff run til ya got speed an rudder authority. With the 6 cylinder engine it still had to be manually trimmed to fly strait and level. (rudder & elevator trim)

Are you using a trim tab? Is it centered? (hull and/or rudders)

I don't know your boat but am I correct in assuming you do NOT have an ultralight hull with all that in it?

Hope this helps some.

Scotty
 
it is a heavy boat rivermaster 15ft caddy motor.the engine stand is the same just had to build support legs for the gearbox.no trim tab.
 
Get the boat up to speed then let off the gas see if and how much it pulls to one side or if it goes straight. If it goes straight then the hull is fine. I'm guessing your hull is torque rolling from all the additional thrust. So either your engine stand is not square or your boat is heavy, or the hull is to small for the thrust you are generating. A quick simple test is take a bunch of pitch out and floor it if the roll goes away or is much less. Then it's not the stand you are overpowering your hull or you have too much weight in the boat for the size of the hull. You are experiencing a very common problem.
 
i will try all the suggestions and if i can come up with a solution i will post it. thanks for your reply's so far.keep more idea's commin though.
 
is it a brand new hull, my buddy bought a new fiberglass hull and his boat did the same thing he took a look and it wasn't strait took a grinder to it then finished it with steel flex and poly, there was a small lip in the on the under side
 
My guess is since it was good before, then it is the extra torque. However, on my last boat it ran on plane great and every now and then would pitch over slightly to the right. I looked at the bottom and saw nothing. I eventually looked a lot closer and saw I had a small piece of fiberglass mat that would flap down at high speeds and act like a trim tab. When I slowed down it would go back up and I'd be fine again. I ground it off and never had a problem after. It was just a little piece of loose glass that caused all that aggravation.
 
Bondsman, I experienced a similar condition with my aluminum boat. Close inspection revealed a bulge in my hull where I struck a submerged fence post. It caused a hook and suction and pulled the boat hard right. A dead blow hammer and block of wood fixed the problem.

Since you have a glass hull, I suspect a possible weak or busted stringer that creates a bulge when under the greatly increased torque of a reduction gear and likely more radical propeller.

Many times, stringers crack at the transom joint, suggest you inspect your left side engine bed stringer, if it's busted, it will create a hook and cause the boat to plunge opposite the hook under load.
 
I KNOW YOU ALREADY KNOW THIS ! BUT THE ROTATION IS DIFFENRET YOU ARE RIDING ON OPPOSITE SIDE OF THE BOAT ! YOUR RIGGING SHOULD BE CHECK ! YOU CHANGE ALOT OF SURFACES !YOUR LEFT RUDDER WAS TAKING THE BLOW OFF YOUR PROP NOW ITS THE RIGHT ONE ! JUST LOOK AT IT WITH A OPEN MIND ! :D
 
You can adjust a lot out with a couple of 3'' trim tabs mounted on each rudder about 12" down from the top.
 
Here's something else that a builder told me recently that I'd never thought much about.
You need at least four runners on your trailer. If you only have three, the hull of the boat (because of the weight of the engine and rigging) will tend to form over the center runner and change the contour of your bottom, whether it's aluminum or fiberglass.

That makes sense to me when you think about all of the bouncing that a boat does when you're towing it.

olf
 
thanks for the input guys .reading yall's posts they are all good when i read fatboys post i think it hit me i never thought on the rudder taking the wind direction different the rudder recieving the push is one i dropped and it is creased and bent on the corner in a direction that might cause my boat to pull.never thinking that somthing so small could cause such a hassle.it is not bent bad but going from a 74inch long 9inch wide 2 blade to a 3 blade 12inch wide 78 long makes a verry big thrust differance.
 
Bondsman, sounds like you might have found it, but don't discount some of the other comments from Thunder, Charles and others. You have more torque now with your gearbox. You'll have to kind of reaquaint yourself to your boat again.

Sounds like a good time to put on a new set of rudders. They don't cost that much and they'll sure look good :) .

olf
 
yeah but i like my rudder art.hate to lose it.and dont worry all suggestions will be tried if no success.
 
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