The best way to be sure of matching hydraulic steering to any boat is to calculate rudder torque using a modified Jorssels formula. All that is needed are some simple details about the boat and the rudder. Factory recommendations are available. However the chart below is a useful guide to selecting a suitable system from the systems numbered 1 to 5 detailed at right.
System
Wheel Turns
Helm
Cylinder
1
4
SeaStar 1.7
BA125-7ATM
2
5
SeaStar 1.7
BA135-7ATM
3
6
SeaStar 1.7
BA150-7ATM
4
4
1/4 SeaStar 2.4
BA150-7ATM
5
5
1/2 SeaStar 2.4
BA175-7TM
Sample System Selection Guide.
Planing Hul
Displacement Hull
Sail
Boat Length up To
Single Engine
Twin Engine
Single Engine
Twin Engine
Single Engine
Pleasure
Work
Pleasure
Work
Pleasure
Work
Pleasure
Work
Pleasure
Work
26FT (8m)
1
4
1
4
2
4
2
4
4
4
32FT (10m)
2
4
1
4
3
4
3
4
4
4
38FT (11.5m)
3
5
2
5
5
5
3
5
4
5
44FT (13.5m)
5
-
3
5
-
-
5
-
5
-
50FT (15m)
-
-
5
-
-
-
-
-
-
-
HOSE & PIPES & HYDRAULIC FLUID
Outboard Hydraulic Hose All inboard systems shown here can use SeaStar outboard Hydraulic Hose Kits. Each kit contains two hoses with fittings ready to install. SeaStar reference H051xx (where xx is the hose length in feet).
SeaStar hydraulic steering systems require the use a high quality hydraulic fluid meeting MIL SPEC H-5606C. This is available locally but can be supplied under following part number.
No. 210613 Hydraulic Fluid 1 Litre.
Nylon Tubing
3/8" outside diameter nylon tubing can be used on inboard powered boats fitted with SeaStar's 1.7 helm. Nylon tubing should not be used where the total tubing run exceeds 30m (100 ft) or on any outboard powered boat. SeaStar's own nylon tubing is available in standard lengths as follows :
3/8" outside diameter copper tubing is recommended for inboard & stern drive powered boats using SeaStar's 2.0 or 2.4 helms and for inboard powered boats with SeaStar's 1.7 helm where the total tube run exceeds 30m (100 ft).
The use of Hose Kit HF5507 for SeaStar aluminium cylinders and HF5508 (No. 210650) for SeaStar brass cylinders is required. Copper tubing can also be used on outboard powered boats with SeaStar brass inboard cylinders in conjunction with Hose Kit HF5508. Specification of Copper Tubing Copper tubing should be annealed copper refrigeration tubing, with 3/8" outside diameter and 0.032" wall thickness (approx 0.8mm).
FLYBRIDGE STEERING
TO ADD A SECOND STEERING STATION YOU'LL NEED
* A second identical Helm. * Add a Station kit No. HF5502 (All Inboards & also Sterndrives with 1.7 Helm). No. HF5501 (All Outboards & also Sterndrives with 2.0/2.4 Helms). * Hose or Pipe (use the same hosing or tubing as used in connecting the primary helm). * Extra Hydraulic Fluid
All inboard systems shown here can use SeaStar outboard Hydraulic Hose Kits. Each kit contains two hoses with fittings ready to install. SeaStar reference H051xx (where xx is the hose length in feet).
