Hydrovane · Wind-vane self-steering

Hydrovane

The Hydrovane is a wind-vane self-steering gear with its own auxiliary rudder: the vane steers that rudder through the drive unit while the boat’s main rudder stays locked, so it also serves as emergency steering. The current VXA drive unit dates from 1986 and comes as the VXA2, whose course is set from the cockpit by a control line, or the VXA1, set by hand at the unit; each installation is put together from a shaft length (S, M, L, X and longer), two brackets (H, E or A) and a Standard, Stubby or extendable XT vane. Hydrovane builds the units near Nottingham, England, and sells spare parts direct. Its maintenance rule is unusual: never grease anything, just rinse with fresh water and spray with a light oil.

Manuals & documents

The links go straight to Hydrovane. We host no manuals or drawings — the manufacturer’s copy is the current one.

Wear parts & part numbers

PartOEM numberAlso fitsNote
Onboard spares kitEssential Kit1,2—Hydrovane’s recommended on-board kit, ordered by name: vane cover #76, locking pins #61 and #62, drive sleeve #19, axle #47 with set screws #40, M10 × 65 bolt sets, set screws (metric and imperial), knob #32/#33 and Loctite 243 threadlocker.
Shear pin#61 · #60 · #621,3,2—Locking pins, all three the same super duplex pin and interchangeable: #61 locks the Hydrovane rudder when motoring and is the designed weak point that fatigues under engine vibration; #60 holds the vane lever when not in use; #62 holds the rudder on the shaft (with R-clip).
Vane cover#761,3—Ripstop nylon, for the Standard, Stubby and XT vane frames #75. The commonest wear item: tropical sun rots it.
Drive sleeve#191,3,4—Plastic sleeve on the ratio rod #35 between the drive rods #36. Grooves after about 15,000 nm; turning it end for end buys time. Units from 2015 have a thicker sleeve.
Ball socket#201,3—Two per unit: the plastic sockets that hold ball screw #57 at the lower end of the con rod. Worn sockets add slop to the steering.
Axle (pivot pin)#47 · #401,3,5—Axles #47 and their set screws #40, eight of each: the stainless pivots of the vane lever #65 and bottom lever #69. The set screws go in with Loctite 243; 3/8 in on units before 2016, 10 mm after. Axles since 2023 have a flat for the screw.
Adjusting knob#21 · #561,3,2—Ratio knob #21 with ratio bolt and spring set #56, sold as a kit; the knob selects ratio positions 1, 2, 3 and N.
Adjusting knob#32 · #33 · #341,3,6,2—Vane knob #32 and axis knob #33 (locks the vane tilt, 0–30°); metric since January 2016, 3/8 in before. Older units can take the metric upgrade: knob #32, M10 vane bolt set #37 and slot collar #4, with the old thread re-tapped to M10 × 1.5. Course clamp knob #34 is on the VXA1 only.
Spares kitPlus Kit1—For remote passages and non-stop racing, on top of the Essential Kit: case screws #2, ball sockets #20, ratio knob #21 with bolt and spring set #56, ratio rod #35, a spare axle #47, 8 m of remote line, M10 and M12 × 150 mounting bolts.
Service kit#24 · #24M · #25 · #26 · #46 · #27 · #28 · #311,7—Shaft bearing kit for shaft assemblies from 2002: top bearing #24, mid bearing #24M, bottom bearing #25, bottom collar #26 with set screw #46, race collar #27 with pin #28 and ball race #31 with 19 nylon balls. The mid bearing is standard since 2008; older 1 1/4 in shafts take it once the machining ridge is filed off.
Plain bearing (bushing)#251,3,8—Shaft bottom bearing (PTFE); shows wear after about 15,000 nm and can be changed with the boat ashore without removing the drive unit. Give shaft diameter and the unit’s age when ordering: tubes from 2002 have a 46 mm bore; before 2002, 46.8 mm (1 1/8 in shaft) or 44.4 mm (1 1/4 in shaft).
Plain bearing (bushing)#813,2—Worm bearings, two per VXA2: the plastic bearings of course-setting worm #80. If they swell and the worm goes stiff, ream them out slightly.
Upgrade kit#3 · #17 · #50 · #57 · #631,9—Con rod and bobbin upgrade kit: bobbin #3, washer and cotter pin #17, bobbin bolt set with Igus bushings #50, ball screw set #57, con rod #63. Standard since spring 2010; on older units it replaces the con rod top casting #68, which is no longer made.
Control line#911,3,10—Remote course-setting line set for the VXA2: 4 mm low-stretch line, 8 m as standard, with block and bungee; the ends are heat-welded into a continuous loop.
Tiller / remote#23 · #41 · #23E1,3—Emergency tiller #23 with stud and tiller screw #41. Extension #23E lets a small tiller pilot steer the Hydrovane rudder when motoring or in very light air.
Case cover#79 · #79LED · #21,3—Frame case cover of the drive unit, held by plastic case screws #2. Also made with a built-in LED stern light: #79LED (3 nm, 1.5 W).
Rudder blade#773,11—The current PA6 nylon rudder (43 in) only goes on the super duplex shaft from 2009. The PP rudder (37 in) suits boats up to 37 ft and is the one for orca areas: it tends to break off without harming the shaft.
Rudder shaft & tube#30S · #30M · #30L · #30X3,11—By length: S 979 mm, M 1208 mm, L 1462 mm, X 1716 mm; longer X+ shafts to order. Super duplex since early 2009. The matching outer tubes are #29S, #29M, #29L and #29X (757, 986, 1240 and 1494 mm).
Bracket casting & sleeve#100 · #106 · #111 · #104 · #109 · #1153,12,13—Transom flanges: H #100, E #106 (transom clamp pair), A #111 (two per bracket); Hydrovane gives 50% off new flanges when the old ones stay on the previous boat. Grey shaft sleeves: H #104, E #109, A #115, machined per bracket and not interchangeable.
Backing plate#951,13—8 mm marine aluminium plate, 240 × 100 mm, undrilled, with fully threaded 150 mm bolt sets. H kit: one plate and two M12 sets; A kit: two plates and four M12; E kit: one plate and two M10.
Mounting pad#100T · #100P · #100TS · #100PS · #106T · #106P · #106PW · #111T · #111P1,11—In teak (T) or HDPE plastic (P). H bracket: #100T 3/4 in, #100P 20 mm, spacers #100TS 1.1 in and #100PS 30 mm. E bracket: #106T 1.1 in, #106P 25 mm, 5° wedges #106PW (pair). A bracket: #111T 3/4 in, #111P 20 mm (pair). Templates are on Hydrovane’s specifications page.
Extended heading tubeXTHT12 · XTHT2011,14—Extended heading tube with con rod: raises the vane pivot by 12 in or 20 in to clear an arch, bimini or davits; comes with top frame #72 fitted.

Numbers checked against the sources below on 12 October 2026. Always confirm against your serial number and exact type before ordering.

Service intervals

TaskInterval
Fresh-water washWhenever you wash the boat: rinse the whole unit with fresh water and soap2
LubricationEvery few months: wash, let dry, then spray the entire unit including the castings with a light aerosol oil such as WD-40; put a corrosion inhibitor (CorrosionX, T-9, LPS 3) on the castings, above all the brackets near the water. Never grease: every joint should rattle2
First serviceAfter the first sail: check the bracket and transom bolts, which will likely need re-tightening; then check them at intervals13
Season checkAfter installation and before every long passage: the final inspection tests (ratio rod, drive sleeve, rudder alignment, tiller flip, vane clearance) and the shaft friction “flick test” with the rudder off2,15
Full serviceCheck the drive sleeve #19 for grooves and the shaft bottom bearing #25 for play: both show wear after about 15000 nm. Rotate or replace the locking pins from time to time, more often if you motor a lot4,2
Storage / winterisingIn port, at anchor and for weeks of non-use: take the Hydrovane rudder off (less wear on bearings and rudder hole, no fouling) and keep the vane out of the sun; replace vane cover #76 once the sun has damaged it2

From Hydrovane’s Operation & Troubleshooting Manual (2026), the Installation Manual (July 2026) and the refurbishment guides. The maker gives no fixed calendar; wear is counted in sea miles.

Specifications

TypeAuxiliary-rudder wind vane: through the drive unit the vane turns its own rudder on a separate shaft while the main rudder stays locked. Doubles as emergency steering (tiller on the drive unit, ratio knob at N)16
VersionsVXA2: course set remotely through a 100 mm (4 in) worm gear and a continuous control line; VXA1: course set by hand with the course clamp knob. Every VXA1 from 1986 on can be converted to VXA2 with a kit11,10
Years builtVXA drive unit since 1986, still the current model; Hydrovane self-steering gears have been made in England since 196817
Max boat displacementOne unit up to 27000 kg (60000 lb), with many good reports above 23000 kg (50000 lb); the old recommended limit was 18000 kg (40000 lb). Above about 25 t the maker suggests two units, and steering power runs short from about 10–12 kn. The installation list (about 1700 boats) runs from 20 ft boats such as the Flicka 20 to yachts over 50 ft and cruising catamarans16,18
DimensionsVanes: Standard 137 × 28 cm (54 × 11 in), Stubby 109 × 51 cm (43 × 20 in), XT 106 × 48 cm, extending to 135 cm (53 in); ripstop nylon on an anodised alloy frame. Rudders: PA6 cast nylon, 43 in, about 0.33 m² (3.5 sq ft), sinks, only on the super duplex shaft (2009 on); PP polypropylene, 37 in, for boats up to 37 ft11
Shaft lengthS 979 mm (stern freeboard up to 860 mm); M 1208 mm (1090 mm); L 1462 mm (1340 mm); X 1716 mm (1600 mm); X+5 1843 mm; X+10 1970 mm; X+20 2224 mm, tip to tip. Outer tubes: S 757, M 986, L 1240, X 1494 mm11
MountingTwo brackets per installation, at least one H. H (hinged): shaft 3.8–11 cm from the transom; E (single strut): from 20 cm; A (double strut): from 40 cm. At most 46 cm of exposed shaft between upper bracket and drive unit; lower bracket 5–25 cm above the bottom bearing11
MountingTransom bolts 316/A4 with backing plates (mandatory): M12 for H and A brackets on new units (H flange #100 since July 2025, A flange #111 since 2026), M10 for the E bracket and older H flanges13
Tightening torquesBracket bolts 40.7 N·m (30 lbf·ft); A-bracket shaft clamp M12 bolts at most 47.5 N·m (35 lbf·ft); drive unit shaft bolts #55 27.1 N·m (20 lbf·ft). Everything else just snug: over-tightening cracks the castings13
Power ratioRatio knob #21: 1 (far left) 15° rudder, 3:1, most power, light air; 2: 25°, 2:1, normal to fresh winds; 3: 35°, 1:1, heavy weather; N (far right) up to 50°, vane disengaged, emergency tiller. Vane axis adjustable 0–30°2
WeightInstalled, by the maker’s examples: light 30 kg (66 lb) with S shaft and H/H brackets; average 37 kg (83 lb) with L shaft and E/H; heavy 51 kg (113 lb) with X shaft and A/H. Nylon rudder alone 10.5 kg (23 lb), about half that in water11
MaterialMain shaft: solid 1 1/4 in (31.75 mm) super duplex stainless since early 2009, about three times as strong as the earlier 316 shaft; turned down to 1 in (25.4 mm) at the top; outer tube 2 in. Super duplex is magnetic, 316 is not. Until 2002 a 1 1/8 in shaft was also made for boats up to 15000 lb11
MaterialCastings: hard-anodised LM25 aluminium alloy plus two silicon-bronze castings; axles and fasteners 316 stainless; bearings glass-filled PET, PTFE and acetal; nylon ball race on the rudder shaft; no welds11
LubricationNever grease the unit: after a fresh-water wash, spray everything with a light oil such as WD-40 and let every joint keep a little play. The only grease goes on stainless bolt threads at installation, against galling2,13

Good to know

  • Never grease a Hydrovane. Rinse it with fresh water and every few months spray the whole unit with a light oil such as WD-40. The joints are meant to have a little play, so salt and dirt cannot make them bind.2
  • The nylon rudder sinks: tie it on with a line of at least 10 mm through its handle, and put tethers on the locking pins and the vane as well. Take the rudder off in port; that spares the bearings and the rudder hole, and it needs no antifouling.2
  • Don’t lock the Hydrovane rudder while sailing; let it trail. If engine vibration makes it chatter when motoring, lash it firmly to a cleat with a rubber snubber; otherwise shaft locking pin #61, the designed weak point, fatigues and breaks. Carry spare pins: all three are interchangeable, and a 1/4 in screwdriver or a nail will do for a while.2
  • Buying a used unit? Make sure it is a VXA (1986 or later): Hydrovane makes parts only for that model. A magnet tells you the shaft: super duplex (from 2009) is magnetic, the old 316 shaft is not. A 1 1/8 in shaft (made until 2002) was meant for boats under 15,000 lb and bends on bigger ones. Check too that the shaft length and brackets suit your transom.12,11
  • If vane and rudder stop working together, or the drive unit has side play, check the eight axles. Push any loose one fully home and refit its set screw with Loctite 243 (3/8 in screws before 2016, 10 mm after).5
  • Stainless bolts gall easily. Keep WD-40 off the threads and use a moly or lithium grease on them instead, tighten by hand only and stay within about 30 lbf·ft (40 N·m): over-tightening cracks the aluminium castings. Each bracket also has its own shaft sleeve, and swapping them cracks the casting too.13

Videos & how-tos

Links to YouTube, nothing embedded. The maker’s own channel comes first; the rest are channels we found clear and correct for this model.

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Sources

  1. hydrovane.com/parts/
  2. hydrovane.com/wp-content/uploads/2026/08/Hydrovane-Operation-Troubleshooting-Manual-2026.…
  3. hydrovane.com/wp-content/uploads/2024/06/PARTS-Part-Schematic-and-List-May-2020.pdf
  4. hydrovane.com/wp-content/uploads/2024/07/Replace-Drive-Sleeve-Jan-2019.pdf
  5. hydrovane.com/wp-content/uploads/2024/07/Loose-Axels-July-2018.pdf
  6. hydrovane.com/wp-content/uploads/2024/07/Metric-Vane-Knob-Bolt-Upgrade-Feb-2019.pdf
  7. hydrovane.com/wp-content/uploads/2024/07/Replace-Shaft-Bearings-May-2018.pdf
  8. hydrovane.com/wp-content/uploads/2024/07/Replace-Shaft-Bottom-Bearing-March-2019.pdf
  9. hydrovane.com/wp-content/uploads/2024/07/Bobbin-and-con-rod-upgrade-Version-1.0.pdf
  10. hydrovane.com/wp-content/uploads/2024/07/Conversion-VXA1-or-VXA2-May-2017.pdf
  11. hydrovane.com/specifications/
  12. hydrovane.com/prices/
  13. hydrovane.com/wp-content/uploads/2026/08/Hydrovane-Installation-Manual-July-2026.pdf
  14. hydrovane.com/wp-content/uploads/2024/07/Extended-Heading-Tube-April-2020.pdf
  15. hydrovane.com/instructions/
  16. hydrovane.com/faqs/
  17. hydrovane.com/the-story/
  18. hydrovane.com/wp-content/uploads/2026/05/Installation-Listing-up-to-2026.pdf

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