SeaStar H-40 Series Heavy Duty Hynautic Helm Assembly
SeaStar H-40 Series Heavy Duty Hynautic Helm Assembly
SeaStar Solutions H-40 Series Heavy Duty Hynautic Helm Assembly
SeaStar H-20 Series Heavy Duty Hynautic Helms are for use with SeaStar's rugged 3-line Hynautic steering systems. These heavy duty helms combine one or two bi-directional axial piston pumps with pilot check and make-up check valving. The result is a unit which prevents rudder feedback, is very efficient (even at low RPM), and is immediately adaptable to multi-station use. A wide choice of helm displacements and cylinder configurations make it easy to spec a system which can handle a variety of large boat performance requirements and accommodate most user preferences.
Features:
- Heavy-duty helm
- Available in different displacements to accommodate most applications
- Available with 1" straight shaft or 3/4" tapered
- Made with marine-grade materials
- Meets or exceeds applicable requirements
- Adaptable to multi-station use
Max steering wheel diameter: 47"
Specifications:
| Part Number | Displacement | Shaft Style Diameter & Type | Keyway | Integral Valving |
| H-41 | 5.50 cu. in. | 1" Straight | 1/4" Square | Yes |
| H-41-2 | 5.50 cu. in. | 3/4" Tapered | #9 Woodruff | Yes |
| H-42 | 4.00 cu. in. | 1" Straight | 1/4" Square | Yes |
| H-42-02 | 4.00 cu. in. | 3/4" Tapered | #9 Woodruff | Yes |
SeaStar H-40 Series Hynautic Helm Application Chart
Note: In the chart below, tubing diameter is based on the distance from cylinder to the farthest helm.
| For Vessel Sizes Up To | Helm Pump Model | Steering Wheel Turns | Requires Cylinder Model | Tubing Diameter - 40 ft. or less | Tubing Diameter 40 ft. or more | Max Suggested HP |
| Planing Hulls | ||||||
| 40' - 50' | H-42 | 4.7 | HC5351 or HC5357 | 1/2" | 5/8" | 750HP |
| 45' - 60' | H-42 | 7.4 | HC5378 or HC5379 | 1/2" | 5/8" | 950 HP |
| 45' - 60' | H-41 | 5.4 | HC5378 or HC5379 | 1/2" | 5/8" | 950 HP |
| 55' - 65' | H-41 | 5.4 | HC5378 or HC5379 | 1/2" | 5/8" | 1200 HP |
| to 70' | H-41 | 10.8 | (2x) HC5378 or HC5379 | 1/2" | 5/8" | 1500 HP |
| to 70' | H-41 | 14.2 | (2x) K-8 | 1/2" | 5/8" | 1500 HP |
| Displacement Hulls - Tug Boats, Net Haulers | ||||||
| 30' - 35' | H-42 | 4.7 | HC5351 or HC5357 | 1/2" | 5/8" | 250 HP |
| 26' - 40' | H-42 | 7.4 | HC5378 or HC5379 | 1/2" | 5/8" | 400 HP |
| 26' - 40' | H-41 | 5.4 | HC5378 or HC5379 | 1/2" | 5/8" | 400 HP |
| 30' - 45' | H-41 | 5.4 | HC5378 or HC 5379 | 1/2" | 5/8" | 450 HP |
| to 50' | H-41 | 10.8 | (2x) HC5378 or HC5379 | 1/2" | 5/8" | 500 HP |
| to 50' | H-41 | 14.2 | (2x) K-8 | 1/2" | 5/8" | 500 HP |
| to 50' | H-41 | 20.0 | (2x) K-9 | 1/2" | 5/8" | 500 HP |
| Displacement Hulls - Work & Pleasure Boats | ||||||
| 40' - 45' | H-42 | 4.7 | HC5351 or HC5357 | 1/2" | 5/8" | 350 HP |
| 40' - 55' | H-42 | 7.4 | HC5378 or HC5379 | 1/2" | 5/8" | 500 HP |
| 40' - 55' | H-41 | 5.4 | HC5378 or HC5379 | 1/2" | 5/8" | 500 HP |
| 45' - 65' | H-41 | 5.4 | HC5378 or HC5379 | 1/2" | 5/8" | 650 HP |
| to 75' | H-41 | 10.8 | (2x) HC5378 or HC5379 | 1/2" | 5/8" | 750 HP |
| to 75' | H-41 | 14.2 | (2x) K-8 | 1/2" | 5/8" | 750 HP |
| Sailboats - Skeg Rudder | ||||||
| 40' - 45' | H-42 | 4.7 | HC5351 or HC5357 | 1/2" | 5/8" | - |
| 40' - 52' | H-42 | 7.4 | HC5378 or HC5379 | 1/2" | 5/8" | - |
| 40' - 52' | H-41 | 5.4 | HC5378 or HC5379 | 1/2" | 5/8" | - |
| 50' - 60' | H-41 | 5.4 | HC5378 or HC5379 | 1/2" | 5/8" | - |
| to 65' | H-41 | 10.8 | (2x) HC5378 or HC5379 | 1/2" | 5/8" | - |
| to 65' | H-41 | 14.2 | (2x) K-8 | 1/2" | 5/8" | - |
| Sailboats - Spade Rudder | ||||||
| 40' - 45' | H-42 | 4.7 | HC5351 or HC5357 | 1/2" | 5/8" | - |
| 35' - 46' | H-42 | 7.4 | HC5378 or HC5379 | 1/2" | 5/8" | - |
| 35' - 46' | H-41 | 5.4 | HC5378 or HC5379 | 1/2" | 5/8" | - |
| 40' - 50' | H-41 | 5.4 | HC5378 or HC5379 | 1/2" | 5/8" | - |
| to 60' | H-41 | 10.8 | (2x) HC5378 or HC5379 | 1/2" | 5/8" | - |
| to 60' | H-41 | 14.2 | (2x) K-8 | 1/2" | 5/8" | - |
Click to Download SeaStar H-40 Series Hynautic Helm Application Chart
California Residents: 
WARNING Cancer and Reproductive Harm - P65Warnings.ca.gov
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Quick Specifications
- Brand
- SeaStar Solutions
- Part Number
- TEL-H-41.1
- Product Type
- Hydraulic Steering
- Availability
- In Stock
- Support
- Fitment help available
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