I have a rudder ?

dean5993 · Post by **dean5993** » Tue Mar 23, 2010 9:23 am

Im replacing my rudder and Im getting all different kinds of info. should I go with a bigger rudder? will I lose performance? My baby is a f26 with a 318 and a bridge,Im replacing the prop with what im told is the best size a 14x10 cupped.Ive only ever owned I.Os this boat seems to be difficult to manuver at idle. since im going to replace the rudder anyway should I put on a larger one? and if so what size works for my boat. Thank you for any help you can give... Brother Trojan owner.

Paul · Post by **Paul** » Tue Mar 23, 2010 11:48 am

Hi Dean,

Take a look at an earlier post titled "I Am Moving!!!" In one of the photos you'll the rudder that I installed on my F-26. This rudder is probably 30-40% larger than the original rudder. It has definatly improved the handling characteristics of the boat at idle speeds and at cruise speed.

Keep in mind that manuvering in tight areas with this boat will always be a little tricky no matter what size rudder you have. When you had an I/O boat, you could direct the thrust in what ever direction you wanted the drive to push or pull the boat. Your Trojan however requires water flow across the rudder to provide any directional capabilities. For instance if the boat is sitting still in the water and you put it into forward gear, you get immediate steering response because your prop is providing thrust across the rudder. Now with the boat sitting still in the water you put it into reverse gear, the thrust is directed towards the bow. The boat will start to move backwards due to the thrust and to port due to an effect called "prop walk". The rudder will provide you no control until the boat gets moving backwards and the rudder has water flowing across it. (this is where a larger rudder helps)

On a right hand rotation boat, you won't really notice the prop walk in forward gear but in reverse the back of the boat will always go to port. Once you get used to it, you can make it work to your advantage. For instance, from a stop, turning the boat 180Â° to port requires a wide ark in forward gear. The same turn to starboard can be done on a dime by turning the rudder to starboard And leaving it there, then shifting back and forth between reverse and forward.

Hope this helps,

larryeddington · Post by **larryeddington** » Tue Mar 23, 2010 5:19 pm

That prop walk is also referred to as side thurst and can be a very valuable asset to handling a single screw boat when understood. it is generated as the result of the prop sitting at an angle in the water which causes one side to take a smaller bite of water than the other, ergo side thrust. If one does not learn to use it a single screw boat can be a bear to manuver at dockside regardless of rudder size.

for what it is worth.

foofer b · Post by **foofer b** » Fri Mar 26, 2010 9:57 pm

If I had the opportunity to get a larger rudder I would definitely do it. The Standard F26 is difficult to manuever in close quarters and hard to maintain steerage in a current or crosswind without significant thrust, which I have had to explain to a marine patrolman one one occasion, when he thought he was going to cite me for violating an idle speed/no wake zone. Also, in maneuvering, know your boat's characteristics. Single screw LH rotating propped boats do not back to port. AT ALL !!! Learned that the hard way in Chinese fire drill number one in my boat. Had to jump out of the boat in chest deep water to keep her from drifting to starboard into the jetty/quay and get her on the trailer. Think thru my docking and trailering maneuvers more carefully now.

captainmaniac · Post by **captainmaniac** » Fri Mar 26, 2010 10:32 pm

With a bit of practice, it is possible to make a single engine configuration back to the 'wrong' side...
1 - put rudder hard over
2 - get the boat moving backwards manually (push or pull from the dock)
3 - shift into reverse, and give it a burst of gas (1000-1200 rpm) for a 2 or 3 seconds to 'really' get it moving
4 - back to idle speed, and TAKE IT OUT OF GEAR

The reverse momentum will flow enough water past the rudder to start pulling the stern the way you want to go, and (most importantly) because you are in neutral you aren't fighting the prop walk anymore. As necessary, hit reverse / gas for a second or two / neutral again to keep it going.

You can't get it to go the 'wrong' way anywhere near as well as it will go the 'right' way, but you can make it pull the wrong way a bit. Or you can at least get it to back up almost straight. But you need enough room around you for it to be safe to get it moving a bit faster than normal...

captainmaniac · Post by **captainmaniac** » Fri Mar 26, 2010 10:32 pm

Having said all that -- a rudder bigger than a postage stamp will definitely help out too !!!!

foofer b · Post by **foofer b** » Sat Mar 27, 2010 6:11 am

Captain maniac, its been my experience that any reverse thrust induces more turning or yaw to starboard than the subsequent coasting backward will produce to port. It's best to just proceed with the mindset that one can only turn/yaw/spin to port. Any kind of wind or current pushing to starboard cannot be overcome.

alexander38 · Post by **alexander38** » Sat Mar 27, 2010 7:36 am

The love of two screws

I do feel for the one screw guys, But I have respect for you guys when pulling in with a high wind and you stick it in the first time. It shows great boat control and skill.

captainmaniac · Post by **captainmaniac** » Sat Mar 27, 2010 11:42 am

foofer b wrote:Captain maniac, its been my experience that any reverse thrust induces more turning or yaw to starboard than the subsequent coasting backward will produce to port. It's best to just proceed with the mindset that one can only turn/yaw/spin to port. Any kind of wind or current pushing to starboard cannot be overcome.

Maybe my experience was a bit different based on model (a 1969 wooden 28'), prop, and rudder size differences compared to what you are running. And yes - wind and current can easily overpower the boat while you are trying to do this manouver, but in light conditions it can work (at least we were able to do it).

foofer b · Post by **foofer b** » Sat Mar 27, 2010 11:59 pm

Captainmaniac, the rudder on mine is maybe 5-6" from front edge to rear and is barely adequate in MHO.

Paul · Post by **Paul** » Mon Mar 29, 2010 9:14 am

Another neat trick to master with a single screw is using a pilling as a pivot point. This is very helpfull when backing out of a slip in a stiff cross wind or when prop walk is working against the the direction you want to turn.

For example, your backing out of a slip in a confined space and you need to turn your bow to port but the prop walk (RH rotation) is pulling your stern to port. While backing out, hug the starboard pilling and when your about half way out shift the boat into forward and crank the wheel hard to port. Give it just enough gas to pivot on the pilling but dont' stop the rearward motion of the boat. Now that your at an angle in the mouth of the slip, put it back in reverse then turn the wheel back to starboard and back up some more. Repeat if necessary.

After all, they dont call it a rub rail for nothing.

foofer b · Post by **foofer b** » Mon Mar 29, 2010 3:04 pm

Short bursts of forward thrust can induce enuff yaw (spin) to help maneuver.