Specifications

Chapter 3 – Boat Systems
Section D. Steering System
Introduction
The steering system (Figure 3-26) is an integrated system made up of three
major components as follows:
• Hydraulic steering cylinder
• Tie bar assembly
• Helm pump assembly
CAUTION !
The hydraulic system operates on standard hydraulic fluid. The
recommended fluid for the steering system is Sea Star Hydraulic Fluid
HA5430 or any hydraulic fluid meeting MIL-H-5606 specifications.
Automatic transmission fluid (ATF) could also be used in an emergency.
The system is filled with fluid and then bled free of any air bubbles.
D.1. Hydraulic
Steering
Cylinder
The Sea Star steering cylinder (Figure 3-27) is a front-mount system that is
compatible with twin-engine, independent tilt. It allows for easy hydraulics
and has a five-turn lock-to-lock response. It is a general purpose cylinder
rated for up to 600 HP on a counter-rotating, twin-engine application.
D.2. Tie Bar
Assembly
The tie bar (Figure 3-27) is a ½-inch solid, stainless steel rod. It has an
adjustable ball joint on one end and a rod end connector on the other. The
rod is protected by a stainless steel stringer tube, which provides added
stability and acts as a stop for the rod end fittings. The purpose of the tie bar
is to provide equal, uniform directional control of the engines, but does not
interfere with independent trim, tilt, and throttle.
D.3. Helm
Pump Assembly
The helm pump assembly (HPA) is mounted in the console and is a multiple
position tilt system. The Momo
®
wheel (Figure 3-28 (RB-HS) and
Figure 3-29, (RB-S)) is attached to the
5
/
8
-inch shaft on the HPA. The
hydraulic lines from the steering cylinder connect into the rear of the HPA.
On the RB-S, an expansion tube/vent is installed in the top of the helm pump
to allow for additional fluid expansion.
3-29
r use brake fluid in the steering system. Use of non-specified fluids may cause
irreparable damage and steering system failure.
Neve