9 Marine Steering Systems 83 COURSE LESSON TITLE PRESENTATION TIME PRESENTATION METHOD MATERIALS REQUIRED Chapter 9 Marine Steering Systems 2 hours Participative Lecture Ch9 PPT slides, computer, projector Objectives Topics Resources & Notes GAIN ATTENTION Review homework answers for chapter 8 Slide 1 OBJECTIVE PRESENTATION Steering Systems Rudders Upon completion of this chapter, the student will understand components and maintenance associated with: mechanical marine tiller and rudder steering systems mechanical marine cable steering systems marine hydraulic steering systems 1. Pintle and Gudgeon System oldest modern steering system sensitive response used on smaller sailboats 2. Balanced Rudder equal surface area little force required difficult to control 3. Semi-Balanced Rudder provides feedback 4. Unbalanced Rudder mechanically simple sensitive response requires most effort 5. Stuffing Boxes Tapered Sleeve Pinches Packing onto Shaft Tighten hand-tight plus 1/6 turn 6. Rudder Post Tube No Packing Required Flush Tube Occasionally and Grease with Teflon Slide 2 Slide 3 Slide 4 Slide 5 Slide 6 Slide 7 Slide 8 Caution: the upper bearing sometimes carries the weight of the rudder. Make sure the rudder is properly supported before disassembly! 7. Tiller and Rudder Maintenance a. Install a pin to retain the pintle-and-gudgeon rudder b. Tie a line if needed c. Carry an emergency tiller d. Lubricate periodically e. Check for loose bolts, rot f. Flush rudder tube occasionally Slide 9
84 9 Marine Steering Systems Objectives Topics Resources & Notes Mechanical Steering 8. Rack and Pinion System Slide 10 Systems Converts Rotary Wheel Motion to Linear Cable Motion Can be Flush Mounted in Helm Station 9. Drum and Cable System Pull-Pull System Based on Cable Wrapped Around Drum in Helm Station Chain Can be Substituted for Wrapped Cable Chain is Connected to Cable Within Pedestal 10. Pull-Pull Cabling Flexible Cable Permits Flexible Installation Permits Multiple Stations Cautions o Do Not Kink the Cable o Maintain with a Periodic Application of Grease Same Principle as Drum and Cable Slides 11 12 Slides 13-14 11. Steering System Maintenance Slide 15 12. Worm Gear Steering Shaft of Helm Station is Connected to a Worm Gear (Screw) An Acme Nut is Connected to Crank on the Rudder Post Lubricate Generously 13. Rod Steering Primitive Linkage System Used on Small Tenders Maintenance: o Oil All Pivots as Needed o Inspect for Loose Fittings 14. Hydraulic Steering Used on Larger Craft Provides a No Feedback Feature Maintenance: o Maintain fluid level o Maintain 30 psi reservoir pressure o Check fittings periodically Slides 16-17 Slide 18 Slide 19 EXERCISE SUMMARY HOMEWORK Answer homework questions for chapter 9
9 Marine Steering Systems 85 Homework Questions 1. All boats are steered: a. from the bow similar to an automobile. b. by deflecting the flow of water. c. by the thrust of an inboard marine engine. d. only with the use of a rudder. 2. In the stern-mounted rudder and tiller system the gudgeon is a: a. rudder stop that prevents loss of the rudder. b. part attached to the tiller. c. lever used to turn the rudder. d. socket that a pintle fits into. 3. Steering gear stuffing boxes: a. are fixtures holding oil for lubrication of steering systems. b. require frequent inspection to check for leakage. c. are best to repack when the boat is in the water. d. should be adjusted to prevent the packing from rubbing on the shaft. 4. What is an important safety step to take with a tiller-mounted rudder on a small sail boat? a. Add weights to the rudder so it won t float out of the gudgeon. b. Install rudder stops to prevent the rudder from acting as a water brake. c. Use a rudder with metal edges to prevent rocks from damaging the rudder edges. d. Install a cotter pin in the pintle to prevent the rudder from floating out of the gudgeon. 5. The two basic, self enclosed, mechanical steering systems in use today are: a. rudder and tiller. b. rack and pinion and rotary. c. pintle and gudgeon. d. drum and cable. 6. In a push-pull cable steering system the rudder is moved by a: a. drum and cable. b. tiller or rod. c. rack and pinion activated by a wheel. d. hydraulic pump. 7. The advantage of the no feedback (NFB) steering system is it: a. isolates the engine s torque from the driver. b. is always under tension without loss of motion. c. has the fastest gear ratio. d. provides heavier helm pressure. 8. Pedestal steering maintenance: a. is not necessary because of the modern materials used. b. should not include testing under a heavy load. c. includes teflon grease on the pedestal shaft bearings. d. includes periodic flushing with water to remove scum.
86 9 Marine Steering Systems 9. What is the most important feature of worm-gear steering? a. Mechanical advantage. b. Easy maintenance. c. Non-reversing action. d. Control flexibility. 10. In a hydraulic steering system the fluid reservoir is pressurized to about pounds per square inch. a. 150 b. 75 c. 30 d. 10 11. Hydraulic steering: a. eliminates kick back from the rudder. b. prevents the use of automatic pilots. c. eliminates the need for fixed stops. d. requires no maintenance.
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