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Discontinued thruster
Lewmar 185TT 5.0 Gen 1 (discontinued): specs, manual and parts
The Lewmar 185TT 5.0 Gen 1 is a tunnel thruster. The motor sits inside the boat and turns a propeller in a tube through the hull. Lewmar has replaced it with its Gen 2 range. Lewmar’s own 2018 thruster controls brochure, which we read on 11 October 2026, calls the units with the black control box the previous generation and the blue box system the next generation. Some dealers still list Gen 1 part numbers.
This page stays up for the owners still running one. It holds the published figures, the part numbers and the manual. You will not find the unit in the thruster finder, the tool here that matches a unit to your boat, or on the compare page. If you need a new thruster, start with either of those.
The published figures
| Type | Tunnel, fixed mount |
|---|---|
| Thrust | 180 lb (82 kgf) |
| As the maker printed it | 82 kgf / 180 lbs (Lewmar manual 500100, electric specification table) |
| Voltage | 12 V or 24 V |
| Motor | 5 kW |
| Tunnel diameter | 185 mm |
| Maker’s boat length | Not published |
| Part number | 59180312V59180424V |
| Last price we read | No price held |
| Manual | Lewmar’s manual for it |
Service parts
These are Lewmar’s own part numbers for the parts an owner replaces, where we could find them: the pin that drives the propeller, the propeller, the anode, the brushes, the switch gear, the fuse and the motor. We read them on 11 October 2026. The last column says how we know each one fits this model. Give the dealer your thruster’s serial number from its label when you order.
| Part | Part number | Lewmar’s name for it | How we know it fits |
|---|---|---|---|
| Drive pin (shear pin) | 559017 | Drive pin | Lewmar’s manual for this model |
| Propeller | 589351 | Propeller | Lewmar’s manual for this model |
| Anode kit | 589350 | Anode Kit | Lewmar’s manual for this model |
| Black box (the controller) | 559003 | Black Box | Lewmar’s manual for this model |
| Solenoid (the motor switch)12 V unit | B11128 | Solenoid | Lewmar’s manual for this model |
| Solenoid (the motor switch)24 V unit | B11129 | Solenoid | Lewmar’s manual for this model |
| Main fuse12 V unit | 589010 | ANL fuse 400 A | Lewmar’s manual for this modelFuse holder 589006 (589013 for the T2 holder). |
| Main fuse24 V unit | See the manual’s fuse table | Fuse table, section 5.1 | Lewmar’s manual for this modelWe could not read this row of the 2007 table with certainty, so we print no rating for it. |
| Tunnel gasket | 553035 | Tunnel gasket | Lewmar’s manual for this model |
| Replacement motor12 V unit | 583028 | Motor Assembly | Lewmar’s manual for this model |
| Replacement motor24 V unit | 583029 | Motor Assembly | Lewmar’s manual for this model |
| Original Gen 1 control panels | 589001, 589002, 589004 | Touch panel, single joystick, double joystick (NOT 2.0 kW) | Lewmar’s manual for this model |
| Gen 2 controls on a Gen 1 unit | 589842 | Black box convertor | Lewmar’s 2018 controls brochureLewmar’s 2018 brochure: it lets a Gen 2 control panel run a black box thruster on the existing boat wiring. |
What the manual and listings say
Lewmar's first-generation 185TT 5.0 tunnel thruster, the one wired through a black control box. It is rated 82 kgf (180 lb) on a 5.0 kW motor in a 185 mm tunnel. Lewmar's 2018 thruster controls brochure calls these the previous generation, replaced by its next-generation blue box system, the Gen 2 range sold today in the same motor sizes.
Lewmar sells a converter so a black box unit can take the newer controls.
Replacement and close alternatives
The replacement: Lewmar 185TT Gen 2, 5.0 kW. Lewmar’s Gen 2 range in the same motor size.
These are Lewmar’s nearest current sizes in the same line, by thrust.
- Nearest below: Lewmar 185TT GEN 2 Tunnel Thruster Package with Joystick, 128 lb, $2,239.
- Nearest above: Lewmar 185TT GEN 2 Tunnel Thruster, 128 to 214 lb, $1,912 to $4,825.
Other makers’ current units of the same style, for the same end, within a quarter of its published thrust:
- Max Power CT80 (12 V), 176 lb, $1,780.
- VETUS Bow 75, 165 to 187 lb, $2,717.
- Quick BTQ 185 DC Bow Thruster + cover, 121 to 187 lb, $4,562 to $6,033.