BayStar Hydraulic Steering: A Comprehensive Guide
BayStar hydraulic steering is a popular choice for single outboard powered boats up to 150 horsepower. It is a more robust and reliable system than cable steering, and it offers a number of advantages, including:
- Smoother and more effortless steering
- Reduced feedback from the engine
- Increased maneuverability
- Improved handling in rough seas
- Reduced wear and tear on the steering system
- How BayStar Hydraulic Steering Works
BayStar hydraulic steering kits come complete with all of the necessary components, including the helm pump, steering cylinder, hydraulic hoses, fittings, fluid reservoir, and mounting hardware. The kits are available in a variety of sizes to fit different boat types and engine sizes.
BayStar hydraulic steering is a two-line system. One line carries fluid from the helm pump to the steering cylinder, and the other line carries fluid back to the helm pump. When the steering wheel is turned, the helm pump forces fluid into the corresponding line, which causes the steering cylinder to move. The steering cylinder is connected to the boat’s rudder or drive unit, so when the cylinder moves, it turns the boat.
BayStar Hydraulic Steering Components
The following are the main components of a BayStar hydraulic steering system:
Helm pump: The helm pump is mounted on the boat’s console and is connected to the steering wheel. It is responsible for pumping fluid to and from the steering cylinder.
Steering cylinder: The steering cylinder is mounted on the boat’s transom and is connected to the rudder or drive unit. It is responsible for turning the boat.
Hydraulic hoses: The hydraulic hoses connect the helm pump to the steering cylinder. They carry the hydraulic fluid that powers the system.
Fittings: The fittings connect the hydraulic hoses to the helm pump, steering cylinder, and other components.
Fluid reservoir: The fluid reservoir stores the hydraulic fluid that circulates through the system.
Installing BayStar Hydraulic Steering
Installing BayStar hydraulic steering is a relatively straightforward process, but it is important to follow the manufacturer’s instructions carefully.
MOUNTING THE HELM
Step 1:
Determine desired mounting position. Ensure that the steering wheel will not interfere with other functional equipment. Check for adequate space behind the dash for fitting and line connections.
Step 2:
Tape the mounting template (found on page 3 of this manual) to the dash and use a center punch to mark the locations of the hole.
Step 3:
Confirm that you will not be drilling into any other equipment then; drill the 3” diameter center hole and the four 5/16″ diameter mounting holes as shown on the template.
Step 4:
Ensuring that the fill port is in the upper position, install the four washers and four nuts onto the mounting studs of the helm pump. Torque nuts to 110 in-lb.
Step 5:
Lightly grease taper of the helm shaft and mount steering wheel to helm.
Step 6:
Install ORB helm fittings into rear of helm, see page 9 for ORB fitting installation.
CYLINDER INSTALLATION
Step 1:
Using a good quality marine grease (such as Evinrude Triple Guard, Quicksilver anti-corrosion, Yamaha marine grease, or equivalent), liberally lubricate the tilt tube, support rods (Item 5) and mount nut (item 7) and then slide the support rods (item 5) into engine tilt tube.
Step 2:
Lightly grease the tiller bolt (Item 2) & partially screw into the appropriate hole in the tiller arm to assure a proper fit. Remove and go to Step 3.
Step 3:
Select appropriate insert diagram from Figure 11 through 15 to determine proper orientation of the cylinder assembly, the tiller bolt and the self-locking nut (Items 8, 2 and 1). Grease and install as indicated.
Step 4:
Screw lubricated mounting nut (item 7) onto tilt tube of the engine. Torque nut 20–25 ft-lb.
Step 5:
Lightly grease the ends of the cylinder shaft and holes of the support rods (item 5). Attach and secure support rods (Item 5) to the cylinder shaft. Tighten using the nuts and washers (Items 4 & 3) as illustrated in Figure 11 through 17.
REVERSING COMPACT CYLINDER ENGINE PLATE
1. DO NOT attempt to reverse the pivot plate with the cylinder installed on the engine. (This may damage the steering shaft, causing irreparable damage.)
2. Remove the two cap screws from one end of the steering cylinder using the 5/32″ Allen head wrench, or socket.
DO NOT pull the gland off the end of the shaft, doing so may damage the seals when you try to reassemble it.
3. Remove the pivot plate and flip over end for end, placing the end hole over the shaft stub on the fixed gland.
4. After removing the cap screws there will be small amounts of debris on the screw. Ensure that any loose debris is removed from inside and the face of the cylinder body.
5. Carefully slide the loose gland back into place so that the gland stub fits into the hole on the pivot plate. Some SeaStar steering fluid applied to the O-ring on the gland may ease reinsertion into the barrel.
6. Align the screw holes on the gland with the threaded holes on the barrel, ensure that the gland face is butted tightly against the end of the barrel, with no debris in between, and fasten using the cap screws removed earlier. Tighten to torque spec 60 in-lb (5 ft-lb).
Cost
The price of BayStar hydraulic steering on eBay varies depending on the specific system you are looking for, but you can expect to pay between $900 and $1,500 for a complete system. Here are some examples of BayStar hydraulic steering systems currently available on eBay:
- Teleflex Hk4200a Baystar Hydraulic Steering Kit 17893 – $959.99
- SeaStar HK4200A-3 BayStar Hydraulic Outboard Steering Kit – $999.99
- BayStar Outboard Steering System – $1,299.99
- BayStar Hydraulic Steering Kit for Single Outboard Boats – $1,499.99
Review
BayStar Hydraulic Steering Install on my Mako Boat!
Double-Pump Hydraulic System
Figure 1.5 shows an application for an unloading valve. It is a circuit that uses a high-pressure, low-flow pump in conjunction with a low-pressure, high-flow pump. A typical application is a sheet metal punch press in which the hydraulic cylinder must extend rapidly over a great distance with low-pressure but high-flow requirements. This occurs under no load. However during the punching operation for short motion, the pressure requirements are high, but the cylinder travel is small and thus the flowrequirementsare low. The circuit in Fig. 1.5 eliminates the necessity of having a very expensive high-pressure, high-flow pump.
When the punching operation begins, the increased pressure opens the unloading valve to unload the low-pressure pump. The purpose of relief valve is to protect the high-pressure pump from over pressure at the end of cylinder stroke and when the DCV is in its spring-centered mode. The check valve protects the low-pressure pump from high pressure, which occurs during punching operation, at the ends of the cylinder stroke and when the DCV is in its spring-centered mode.
Regenerative Cylinder Circuit
Figure 1.3 shows a regenerative circuit that is used to speed up the extending speed of a double-acting cylinder. The pipelines to both ends of the hydraulic cylinder are connected in parallel and one of the ports of the 4/3 valve is blockedby simply screwing a thread plug into the port opening. During retraction stroke, the 4/3 valve is configured to the right envelope. During this stroke, the pump flow bypasses the DCV and enters the rod end of the cylinder. Oil from the blank end then drains back to the tank through the DCV.
When the DCV is shifted in to its left-envelope configuration, the cylinder extends as shown in Fig. 1.3.The speed of extension is greater than that for a regular double-acting cylinder because the flow from the rod end regenerates with the pump flow Qp to provide a total flow rate Qt.
Pump-Unloading Circuit
Figure 1.4 shows a hydraulic circuit to unload a pump using an unloading valve.When the cylinder reaches the end of its extension stroke, the pressure of oil rises because the check valve keeps the high-pressure oil. Due to high-pressure oil in the pilot line of the unloading valve, it opens and unloads the pump pressure to the tank.
When the DCV is shifted to retract the cylinder, the motion of the piston reduces the pressure in the pilot line of the unloading valve. This resets the unloading valve until the cylinder is fully retracted. When this happens, the unloading valve unloads the pump due to high-pressure oil. Thus, the unloading valve unloads the pump at the ends of the extending and retraction strokes as well as in the spring-centered position of the DCV.
Control of a Double-Acting Hydraulic Cylinder
The circuit diagram to control double-acting cylinder is shown in Fig. 1.2. The control of a double-acting hydraulic cylinder is described as follows:
1. When the 4/3 valve is in its neutral position (tandem design), the cylinder is hydraulically locked and the pump is unloaded back to the tank.
2. When the 4/3 valve is actuated into the flow path, the cylinder is extended against its load as oil flows from port P through port A. Oil in the rod end of the cylinder is free to flow back to the tank through the four-way valve from portB through portT.
3. When the 4/3 valve is actuated into the right-envelope configuration, the cylinder retracts as oil flows from port P through port B. Oil in the blank end is returned to the tank via the flow path from port A to port T.
At the ends of the stroke, there is no system demand for oil. Thus, the pump flow goes through the relief valve at its pressure level setting unless the four-way valve is deactivated.
Simple Pressure-Relief Valve
The most widely used type of pressure control valve is the pressure-relief valve because it is found in practically every hydraulic system. Schematic diagram of simple relief valve is shown in Fig. 1.1 and three-dimensional view is shown in Fig. 1.2. It is normally a closed valve whose function is to limit the pressure to a specified maximum value by diverting pump flow back to the tank. A poppet is held seated inside the valve by a heavy spring. When the system pressure reaches a high enough value, the poppet is forced off its seat. This permits flow through the outlet to the tank as long as this high pressure level is maintained. Note the external adjusting screw, which varies spring force and, thus, the pressure at which the valve begins to open (cracking pressure)(Fig. 1.3).
It should be noted that the poppet must open sufficiently to allow full pump flow. The pressure that exists at full pump flow can be substantially greater than cracking pressure. The pressure at full pump flow is the pressure level that is specified when referring to the pressure setting of the valve. It is the maximum pressure level permitted by the relief valve.
If the hydraulic system does not accept any flow, then all the pump flow must return to the tank via the relief valve. The pressure-relief valve provides protection against any overloads experienced by the actuators in the hydraulic system. Of course, a relief valve is not needed if a pressure-compensated vane pump is used. Obviously one important function of a pressure-relief valve is to limit the force or torque produced by hydraulic cylinders or motors.
The main advantage of direct-acting relief valves over pilot-operated relief valves is that they respond very rapidly to pressure buildup. Because there is only one moving part in a direct-acting relief valve, it can open rapidly, thus minimizing pressure spikes.
Telescopic Cylinder
A telescopic cylinder (shown in Fig. 1.6) is used when a long stroke length and a short retracted length are required. The telescopic cylinder extends in stages, each stage consisting of a sleeve that fits inside the previous stage. One application for this type of cylinder is raising a dump truck bed. Telescopic cylinders are available in both single-acting and double-acting models. They are more expensive than standard cylinders due to their more complex construction.
They generally consist of a nest of tubes and operate on the displacement principle. The tubes are supported by bearing rings, the innermost (rear) set of which have grooves or channels to allow fluid flow. The front bearing assembly on each section includes seals and wiper rings. Stop rings limit the movement of each section, thus preventing separation. When the cylinder extends, all the sections move together until the outer section is prevented from further extension by its stop ring. The remaining sections continue out-stroking until the second outermost section reaches the limit of its stroke;this process continues until all sections are extended, the innermost one being the last of all.
For a given input flow rate, the speed of operation increases in steps as each successive section reaches the end of its stroke. Similarly, for a specific pressure, the load-lifting capacity decreases for each successive section.
Double-Acting Cylinder with a Piston Rod on One Side
Figure 1.4 shows the operation of a double-acting cylinder with a piston rod on one side. To extend the cylinder, the pump flow is sent to the blank-end port as in Fig. 1.4(a). The fluid from the rod-end port returns to the reservoir. To retract the cylinder, the pump flow is sent to the rod-end port and the fluid from the blank-end port returns to the tank as in Fig.1.4(b).
Unloading Valves
Unloading valves are pressure-control devices that are used to dump excess fluid to the tank at little or no pressure. A common application is in high-low pump circuits where two pumps move an actuator at a high speed and low pressure.The circuit then shifts to a single pump providing a high pressure to perform work.
Another application is sending excess flow from the cap end of an oversize-rod cylinder to the tank as the cylinder retracts. This makes it possible to use a smaller, less-expensive directional control valve while keeping pressure drop low.
Flow Trough Orifice
Orifices are a basic means for the control of fluid power. Flow characteristics of orifices plays a major role in the design of many hydraulic control devices. An orifice is a sudden restriction of short length (ideally zero length for a sharp-edged orifice) in a flow passage and may have a fixed or variable area. Two types of flow regime exist (Fig. 3-10), depending on whether inertia or viscous forces dominate. The flow velocity through an orifice must increase above that in the upstream region to satisfy the law of continuity. At high Reynolds numbers, the pressure drop across the orifice is caused by the acceleration of the fluid particles from the upstream velocity to the higher jet velocity. At low Reynolds numbers, the pressure drop is caused by the internal shear forces resulting from fluid viscosity.
