B&G Hydraulic Ram T2 24V Autopilot Drive Unit
B&G Hydraulic Ram T2 24V Autopilot Drive Unit — Product description
The B&G Hydraulic Ram T2 24V (MPN RAM-T2-24V, UPC 738087005433) is B&G's mid-size sealed hydraulic linear actuator for marine autopilot drive applications - the self-contained drive unit that gives B&G autopilot computers (H5000 and NAC3) the physical force to move your boat's mechanical primary steering when the autopilot is engaged. This is the 24-volt version sized for vessels with mechanical primary steering (cable, push-pull, or rod-and-bevel steering systems - NOT for boats that already have hydraulic primary steering, which use a different B&G hydraulic pump drive instead). Self-contained sealed construction is the defining feature: the RAM T2 combines the hydraulic cylinder, the pump, the bi-directional motor, the electromagnetic clutch, and the oil reservoir into one pre-filled sealed unit. No external pump to mount separately, no external reservoir to plumb, no hydraulic lines to run. Just bolt the ram between the boat structure and the tiller arm or quadrant, run the 24V power lead and the clutch control wire to your autopilot computer, and you're done. Maximum intermittent thrust of 675 kg handles realistic steering loads on mid-size sailboats and powerboats (typically 30-45 ft sailboats and 28-40 ft powerboats with manageable rudder loads). Hard-over time is 9 seconds nominal - fast enough for responsive autopilot course correction. Internal relief valves set at 62 bar protect the ram from rudder strikes, groundings, and over-pressure damage from the autopilot commanding hard-over against a mechanical end-stop. When autopilot is OFF, the clutch disengages and the ram piston moves freely with your wheel input - so manual steering retains full feel and responsiveness with only 7 kg of back-drive resistance at a 12-second hard-over cycle. Construction is aluminum body with SP270 protective coating, chrome-plated stainless steel piston rod, and Nitrile + PTFE seals - the materials spec for sustained marine service life. Pre-filled at the factory with mineral-based ISO VG10 hydraulic oil. IP44 protection rating, BS EN 28846:1993 ignition protection certified, 1-meter 2-core flying lead for power connection. Compatible exclusively with B&G H5000 and NAC3 autopilot computers.
The B&G Hydraulic Ram T2 24V Drive Unit is a self-contained sealed hydraulic linear actuator that gives B&G autopilot computers (H5000 and NAC3) the physical mechanical force needed to move your boat's primary steering when the autopilot is engaged. This is the 24-volt T2 size in B&G's autopilot drive lineup, sized for typical mid-size sailboat and powerboat applications.
Self-contained sealed construction - the defining feature. Traditional autopilot hydraulic drive systems require multiple separate components: a hydraulic cylinder mounted at the rudder, a hydraulic pump mounted somewhere accessible, a fluid reservoir, and hydraulic lines connecting everything. Installation is a multi-day job and any leak in the plumbing kills the system. The B&G RAM T2 design combines the cylinder, pump, bi-directional motor, electromagnetic clutch, and oil reservoir into one pre-filled sealed unit. The entire hydraulic system is enclosed within the ram body - no external hydraulic lines, no external reservoir, no external pump. Install is dramatically simpler: bolt the ram to the boat structure (mounting bracket on the hull side) and to the tiller arm or steering quadrant (rod-end on the actuator side), connect 24V power and the autopilot control wires, and the system is operational.
What this drive unit is FOR. The RAM T2 is designed for vessels with mechanical primary steering that can be back-driven - meaning steering systems where the rudder can physically push the wheel (or vice versa) without resistance from a separate hydraulic helm pump. This includes cable steering, push-pull (Morse) steering, rod-and-bevel steering, and direct tiller steering. The RAM T2 attaches in parallel with the existing mechanical steering and acts on the tiller arm or steering quadrant. When autopilot is OFF, the clutch disengages and the ram piston moves freely with whatever the helm is doing. When autopilot is ON, the clutch engages and the motor drives the ram to extend or retract, which moves the tiller and steers the boat.
What this drive unit is NOT for. Boats with hydraulic primary steering (where the wheel turns a helm pump that pushes fluid through hoses to a steering cylinder at the rudder) do NOT use the RAM T2 - they use a B&G hydraulic pump drive instead (different product, plumbs into the existing hydraulic steering circuit). The distinction matters: if you have hydraulic primary steering and install the RAM T2 in parallel, you'll fight the existing hydraulic steering loop and neither system will work correctly. Confirm your steering type before ordering.
Performance specs - what the 675 kg thrust means. Maximum intermittent thrust of 675 kg (1,488 lb) is the peak force the RAM T2 can exert on the tiller or quadrant during hard-over commands. Realistic steering load on a typical 35 ft sailboat or 30 ft powerboat is well under 200 kg in normal conditions, with peak loads up to 300-400 kg in heavy seas with significant rudder load. The 675 kg rating gives substantial safety margin for the typical install. For boats requiring more thrust (heavier displacement sailboats over 45 ft, powerboats over 40 ft with large rudders), the larger RAM T3 (or higher) is the appropriate choice. Underspeccing the ram size leads to autopilot performance problems in heavy weather where the ram can't keep up with rudder load.
9-second hard-over time. The nominal hard-over time (full rudder travel from one extreme to the other) is 9 seconds, which is the sweet spot for autopilot course-keeping. Faster hard-over times would let the autopilot react more aggressively but at the cost of higher peak power draw and more wear on the steering linkage. Slower hard-over times would reduce wear but cause the autopilot to lag behind sea state corrections. 9 seconds is what most major autopilot brands target for this displacement class.
Internal relief valves at 62 bar. Built into the ram's hydraulic circuit are internal relief valves set to open at 62 bar of hydraulic pressure. These valves protect the ram body, seals, and mounting hardware from pressure spikes during three common events: (1) Rudder strikes - hitting an underwater obstruction at speed sends a sudden load spike back through the rudder linkage to the ram. The relief valve bleeds the pressure spike so the ram doesn't blow seals or tear out of its mounts. (2) Groundings - running aground with the rudder turned creates extreme rudder loads. The relief valve protects the ram from damage. (3) Autopilot hard-over commands against end-stops - if the autopilot commands hard-over and the rudder hits its mechanical stop, pressure builds in the cylinder. The relief valve dumps the over-pressure rather than letting it stress the system. The 62 bar setting is calibrated to operate above normal working pressures but below damaging levels.
Back-drive force - only 7 kg at 12-second hard-over. When autopilot is OFF and you're steering by hand, the ram needs to move freely with your wheel input. The RAM T2 spec rates back-drive force at 7 kg measured during a 12-second full hard-over cycle - which means the wheel feels essentially normal during manual steering. This is the key spec that separates good hydraulic ram drives from cheap ones. Cheap rams have high back-drive resistance because of poorly-designed bypass paths in the hydraulic circuit - you can feel the ram dragging on the wheel during manual steering. The 7 kg back-drive on the RAM T2 is essentially undetectable in normal helm feel.
Electromagnetic clutch. The clutch is what disengages the motor from the ram when autopilot is OFF. Energizing the clutch coil (12 watts continuous power) engages the clutch and connects the motor to the hydraulic pump. De-energizing releases the clutch and the ram piston floats freely with the steering input. The clutch operates at 24V to match the motor voltage and is controlled by the autopilot computer's drive output.
Compatible autopilot computers. The RAM T2 24V works with B&G's H5000 and NAC3 autopilot computers. The H5000 is B&G's high-end sailboat autopilot computer (for serious offshore cruising and racing). The NAC3 is the standard autopilot computer used across the B&G lineup. The RAM T2 will NOT directly interface with older B&G computers (older Pilot generations) or with other-brand autopilot computers - the drive output voltage and control protocol are specific to the H5000 and NAC3.
Construction materials. Body: aluminum to BS 1490 spec, with SP270 protective coating for marine corrosion resistance. Piston rod: chrome-plated stainless steel for smooth low-friction action and long seal life. Seals: Nitrile + PTFE combination - Nitrile primary for hydraulic seal integrity, PTFE for low-friction operation. Pre-filled at the factory with mineral-based ISO VG10 hydraulic oil sized for the unit's reservoir volume - no oil top-up needed at install (or for years of normal operation).
Temperature and protection ratings. Operating temperature -20 degrees C to +65 degrees C handles essentially any cruising environment from cold-water northern climates to tropical heat. IP44 protection rating - protected against ingress of objects greater than 1mm and against water splashes from any direction. The IP44 rating handles typical boat-bilge conditions (occasional spray, condensation, brief water immersion) but the ram should not be installed in a permanently-wet bilge location. BS EN 28846:1993 ignition protection certified for use in compartments where flammable vapors may be present (essential for installation in engine rooms or fuel-tank compartments).
Electrical connection. 1-meter 2-core flying lead exits the ram body for the 24V power connection. Extend the lead with appropriately-sized marine wire (typically 14 AWG minimum for the 100W motor at 24V, with 10A fuse protection at the battery). The clutch control wire and autopilot computer interface are separate connections per the B&G installation manual.
Installation considerations. The RAM T2 mounts in parallel with the existing steering linkage - one end bolts to a sturdy point on the hull or bulkhead (the fixed end), the other end attaches to the tiller arm or steering quadrant (the moving end). The two attachment points must be precisely positioned so the ram operates within its stroke range across the full rudder travel - too short and the ram bottoms out before full rudder, too long and the rudder hits the end-stop before the ram does. B&G publishes detailed install specifications including the geometric requirements for the mount points relative to the rudder pivot. Most installs are done by professional marine electricians or autopilot installation specialists - it's not a casual DIY project.
Warranty. Standard B&G warranty applies - check the current warranty terms on the B&G website at purchase. B&G has established global service support.
Key Features
- B&G self-contained sealed hydraulic linear actuator for autopilot drive on vessels with mechanical primary steering (cable, push-pull, rod-and-bevel)
- All-in-one design: cylinder, pump, bi-directional motor, electromagnetic clutch, and oil reservoir combined in one pre-filled sealed unit
- Dramatically simpler install than traditional multi-component autopilot drives - no external pump, no external reservoir, no external hydraulic lines
- Maximum intermittent thrust 675 kg (1,488 lb) sized for typical 30-45 ft sailboats and 28-40 ft powerboats
- 9-second nominal hard-over time - sweet spot for responsive autopilot course-keeping without excessive system wear
- Internal relief valves at 62 bar protect against rudder strikes, groundings, and hard-over end-stop events
- Only 7 kg back-drive resistance at 12-sec hard-over - wheel feels essentially normal during manual steering when autopilot is off
- Compatible exclusively with B&G H5000 and NAC3 autopilot computers
- 24V DC motor with 100W power, max current approximately 11A at 25% duty cycle
- Electromagnetic clutch (12W continuous coil power) disengages motor when autopilot is OFF for free wheel movement
- Operating temperature -20°C to +65°C handles cold-water cruising to tropical heat
- IP44 protection rating plus BS EN 28846:1993 ignition protection certified for engine room and fuel compartment installation
- Aluminum body (BS 1490) with SP270 protective coating, chrome-plated stainless steel piston rod, Nitrile + PTFE seals
- Pre-filled at factory with mineral-based ISO VG10 hydraulic oil - no install-time oil top-up needed
- 1-meter 2-core flying lead for 24V power connection (extend with marine wire to battery)
- NOT for vessels with hydraulic primary steering - those use a different B&G hydraulic pump drive
Why Buy from NVN Marine
- Authorized B&G reseller, full manufacturer warranty
- NMEA member and ABYC certified, advice from real boat techs
- Same-day shipping before 3 PM ET on in-stock items
- NY headquarters and Fort Lauderdale flagship retail store
Genuine B&G RAM-T2-24V hydraulic autopilot drive unit. Free shipping from NVN Marine on this $2,599 autopilot drive upgrade. Backed by B&G manufacturer warranty. Professional install strongly recommended.
Technical specifications
| Title | B&G Hydraulic Ram T2 24V Autopilot Drive Unit |
|---|---|
| Brand | B&G |
| Manufacturer Part Number | RAM-T2-24V |
| UPC | 738087005433 |
| Product Type | Self-contained hydraulic linear actuator for autopilot drive |
| Compatible Autopilots | B&G H5000 and NAC3 autopilot computers |
| Steering Compatibility | Mechanical primary steering (cable, push-pull, rod-and-bevel) - NOT hydraulic primary steering |
| Maximum Thrust | 675 kg (1,488 lb) intermittent |
| Hard-Over Time | 9 seconds nominal |
| Back-Drive Resistance | 7 kg at 12-second hard-over cycle |
| Relief Valve Setting | 62 bar (protects against rudder strikes, groundings, end-stop events) |
| Operating Temperature | -20°C to +65°C |
| Motor Voltage | 24 VDC nominal |
| Motor Power | 100 watt |
| Maximum Current | Approximately 11A at 25% duty cycle |
| Rotation | Reversing (bi-directional) |
| Clutch Coil Power | 12 watt continuous |
| Protection Rating | IP44 |
| Ignition Protection | BS EN 28846:1993 certified for fuel/engine compartment installation |
| Electrical Connection | 1-meter 2-core flying lead |
| Body Material | Aluminum BS 1490 with SP270 protective coating |
| Piston Rod | Chrome-plated stainless steel |
| Seal Material | Nitrile + PTFE |
| Hydraulic Oil | Pre-filled mineral-based ISO VG10 |
| Warranty | Standard B&G manufacturer warranty |
Frequently asked questions
Does it work with my non-B&G autopilot computer?
No. The RAM T2 24V is specifically compatible with B&G H5000 and NAC3 autopilot computers only. The control voltage, clutch drive protocol, and electrical interface are B&G-specific. For other-brand autopilots, use the matching drive unit from that brand. There is no universal autopilot drive that works across brands - each autopilot manufacturer specifies their own drive units with proprietary interfaces.
What's the difference between RAM T1, T2, and T3?
Size and thrust capacity. The T1 is the smallest (lower thrust, lower stroke, for smaller boats). The T2 (this product) is the mid-size unit, sized for typical 30-45 ft sailboats and 28-40 ft powerboats with normal steering loads. The T3 is the largest, for heavier displacement sailboats over 45 ft and powerboats over 40 ft with large rudders. Pick the size that matches your boat's displacement and rudder load - underspeccing creates autopilot performance problems in heavy weather, overspeccing wastes money and consumes more space and power than needed.
What's the difference between 12V and 24V versions?
Voltage. The 24V version (this product, RAM-T2-24V) runs on the boat's 24V house electrical system - typical on larger sailboats and many European-built boats. The 12V version (RAM-T2-12V, separate product) runs on 12V electrical systems - typical on most outboard-powered boats and many smaller sailboats. Match the voltage to your boat's electrical system - using the wrong voltage will either underdrive the motor (running 24V unit on 12V system delivers about half the rated thrust) or destroy it (running 12V unit on 24V system over-volts the motor).
Do I have mechanical or hydraulic steering?
Critical question - the RAM T2 only works on mechanical steering. Mechanical steering: turning the wheel pulls cables, push-pull rods, or rod-and-bevel linkage that physically moves the rudder. You can usually trace the steering linkage from the wheel to the rudder. Hydraulic steering: turning the wheel turns a helm pump that pushes hydraulic fluid through hoses to a steering cylinder at the rudder. You can usually see the hoses going from the helm pump to the rudder. If you have hydraulic steering, you need a B&G hydraulic pump drive (different product) - the RAM T2 won't work on your boat.
How hard is the install?
Significant. The RAM T2 must be precisely positioned with the correct geometric relationship to the rudder pivot point so that the ram's stroke matches the rudder's travel range. Wrong geometry means either the ram bottoms out before the rudder reaches its end-stops (under-rotation), or the rudder hits its stops before the ram does (over-stress on linkage). B&G publishes detailed install geometry requirements but most owners hire a professional marine electronics installer or autopilot specialist for this work. Realistic install cost: $1,500-3,000 in labor on top of the parts cost. DIY is feasible for owners with serious mechanical experience but not a casual project.
Will it work in my engine room or fuel compartment?
Yes - the RAM T2 carries BS EN 28846:1993 ignition protection certification, which specifically qualifies it for installation in compartments where flammable vapors may be present (engine rooms, fuel tank compartments, propane lockers). The internal electronics are designed to prevent ignition of vapors during normal operation. This is critical for sailboat installs where the autopilot ram often mounts in the engine room or aft lazarette adjacent to fuel tanks.
How much does it draw from my house battery?
100W motor at 24V = approximately 4 amps continuous when the motor is running. Peak current draw during heavy load can briefly hit 10-11 amps. Plus 12W (0.5 amps at 24V) continuous when the clutch is engaged (autopilot ON, even when the ram isn't actively moving). For typical autopilot use averaging 20-30% duty cycle (the motor only runs to make corrections, not continuously), average current draw is about 1-2 amps continuous when autopilot is engaged. Negligible impact on a typical 200+ Ah house bank for multi-day passages.
Does it need maintenance?
Minimal. The unit is pre-filled and sealed at the factory - no oil top-up or filter changes during normal service life. Recommended periodic checks: visually inspect for hydraulic fluid leakage around the seals (annually), check the mounting hardware for any signs of working loose, verify the clutch engages cleanly when autopilot is engaged. Internal seal life is typically 8-15 years in normal service before significant performance degradation. Don't try to open the ram body for internal maintenance - it's sealed and the internal hydraulic circuit isn't user-serviceable.
How fast does it move the rudder?
9-second nominal hard-over time across full rudder travel - this is the speed the autopilot uses for course corrections and is calibrated to balance responsiveness with system wear. The ram can be commanded to move at slower speeds (autopilot can pulse-modulate the motor for slower precise positioning). Maximum manual override is whatever your wheel input commands when the clutch is disengaged - the ram moves freely with the wheel at whatever speed you turn it.
What if the autopilot fails - can I steer manually?
Yes - that's the whole point of the back-driveable design. When the autopilot computer is OFF (or has failed), the clutch coil de-energizes and the ram piston moves freely with whatever input comes from the wheel. You retain full manual steering with only 7 kg of additional resistance from the ram (essentially imperceptible in normal helm feel). The mechanical primary steering linkage handles the actual steering force - the ram just adds free-floating mass when not engaged.
What about lightning protection or surge events?
The RAM T2 itself has standard marine electronics surge tolerance but is not specifically lightning-hardened. Best practice: install the boat's house electrical system with appropriate surge protection on the autopilot circuit, ground the ram body properly per the install instructions, and disconnect the autopilot during lightning storms. Direct lightning strikes typically destroy any marine electronics regardless of brand or design.
What's the warranty?
Standard B&G marine electronics warranty - check B&G website for current terms. B&G has well-established global service support. Warranty typically covers manufacturing defects but not damage from improper installation (incorrect geometry, wrong voltage, inadequate mounting structure), lightning damage, or normal wear after the warranty period. For warranty service, contact B&G or your installing dealer with proof of purchase and serial number.
