MerCruiser · Sterndrive

MerCruiser Bravo Three

The Bravo Three is MerCruiser’s sterndrive with two propellers on concentric shafts that turn in opposite directions, which cancels propeller torque and gives strong grip for sport cruisers and heavy day boats behind big-block petrol V8s and diesels. It came out in 1993 and is still built as Bravo Three, Three X and Three XR; the service and anode kits change with the drive serial number, at 0M179452 (2003) and 2A514803 (2017). There is no water pump in the drive: cooling water comes in through the leg, but the impeller sits in a belt-driven seawater pump on the engine. The single-propeller Bravo One and Bravo Two share the Bravo transom assembly, bellows and gimbal bearing, but not the gear housing, propellers or anode kits.

Manuals & documents
Wear parts & part numbers
Service intervals
Specifications
Good to know
On the marketplace

Manuals & documents

The links go to MerCruiser’s own documents — some as archived copies of pages the maker has since taken down. We host no manuals or drawings.

Operation manual 4.5L/6.2L MPI (2019, 90-8M0163863) Operation manual servicelit.mercurymarine.com · PDF · EN
Operation manual carbureted engines, Alpha/Bravo models (2018, 90-8M0149738) Operation manual servicelit.mercurymarine.com · PDF · EN
Operation manual 8.2L MAG / H.O. / SeaCore with ECT (2018, 90-8M0145507) Operation manual servicelit.mercurymarine.com · PDF · EN
Owner’s manual 496 MAG, Bravo models (2010, 90-8M0053276) Operation manual servicelit.mercurymarine.com · PDF · EN
Owner’s manual carbureted engines, Alpha/Bravo models (2002, 90-860171023) Operation manual servicelit.mercurymarine.com · PDF · EN
Owner’s manual petrol engines, Bravo models (1998, 90-860171985) Operation manual servicelit.mercurymarine.com · PDF · EN
Mercury Marine literature portal: owner’s manuals by serial number or model; also lists the printed service manuals #39 Bravo Sterndrives (90-865612010 / 865612T02) and Bravo Sterndrive (8M0185811) Manual portal mnappsp.mercurymarine.com · EN
Brunswick publications store: printed MerCruiser service manuals Manual portal publications.brunswick.com · EN
MerCruiser sterndrives and inboards brochure (8M0189531) Brochure mercurymarine.widen.net · EN
Mercury product page Bravo Three, Three X and Three XR (archived December 2025) Archived maker page web.archive.org · EN

Wear parts & part numbers

Part	OEM number	Also fits	Note
Service kit	`8M0215917`^1,2	—	Bravo Three 2017 and newer, s/n 2A514803 and up: Mercury’s 300-hour kit with the same scope as 8M0147076 (gear oil not included).
Service kit	`8M0147076`^3,4	—	Bravo Three 2003–2016, s/n 0M179452–2A514802: Mercury’s 300-hour kit with drive installation gaskets, aluminium anode kit, gear housing drain seals, transom (bellows) kit, shift cable kit and fill/drain screws. Gear oil is not included.
Service kit	`8M0147075`^5,6	—	Bravo Three 1995–2002 (s/n 0F345868–0M179451) and Bravo Two 1988–2016: the same scope as the later kits.
Transom seal kit (bellows)	`8M0095485`^7,10,9,11replaces 30-803100T1	Sierra `18-8212`^7,8Sierra `18-8219`^7,9	Transom seal (bellows) kit for Bravo One, Two and Three with exhaust bellows, 2016 and older (s/n up to 2A514802), also Blackhawk: U-joint bellows 86840A05, exhaust tube 78458A1, exhaust bellows 18654A1, gimbal bearing 30-862540A3, shift cable bellows 74639A2, water hose 32-43437 and drive gasket kit 16755Q1 (contents as listed by PowerBoatSupply). A kit number for 2017 and newer drives could not be confirmed.
U-joint bellows	`8M0062406`^{12,13,14,15,16}replaces 86840A3replaces 86840A05	—	U-joint (drive shaft) bellows for Bravo and Blackhawk drives from 1991 (also Vazer), clamps included.
Exhaust bellows	`8M0124227`^12,16,17,18replaces 18654A1	—	Exhaust bellows for Bravo and Blackhawk, the same part as on Alpha, MC-I, R, MR and Vazer; stainless clamps included.
Shift cable bellows	`74639A2`^19,20,21	—	Shift cable bellows for all MerCruiser sterndrives with a shift cable in the drive; clamps included.
Gimbal bearing	`30-879194A01`^19,22,20replaces 30-862540A3	—	Gimbal bearing for Bravo transom assemblies from 1996 (also Alpha One Gen II from 1998 and Vazer); the sealed 30-879194A01 replaces 30-862540A3. Included in transom kit 8M0095485.
Hose	`32-43437`^19,20,10	—	Water hose from the gimbal housing to the bell housing; part of transom kit 8M0095485.
Gasket set	`16755Q1`^23,24,25,26	—	Bell housing installation kit for Bravo One, Two and Three: six gaskets and O-rings for fitting the drive to the transom assembly. Replace it every time the drive comes off.
Shift cable	`865437A02`²⁷replaces 815471A6	—	Lower shift cable kit for Bravo One, Two and Three. Hardin’s Bravo Three catalogue shows it replacing 815471A6, the number on Crowley’s 1998 diagram.
Lower unit seal kit	`26-76868A04`^28,29,30replaces 26-76868A2	—	Gear housing seal kit for Bravo One, Two, Three and X; replaces 26-76868A2 from Crowley’s 1998 Bravo Three diagram.
Drive shaft housing seal kit	`26-16709A2`^32,33,31	Sierra `18-2643`³¹	Drive shaft housing (upper) seal kit for Bravo One, Two, Three, X, XR and XZ: seals, O-rings and gaskets for the upper drive.
Propeller shaft seal	`26-861694`^28,34	—	Oil seal in the bearing carrier (propeller shafts) of Bravo Three, Three X and Blackhawk. The second carrier seal, 26-861695, is no longer made (Hardin) or available (Crowley).
Propeller nut	`8M0105210`^28,35,36,37replaces 11-859131	—	Front propeller nut (nylon insert), 136 Nm. Replaces 11-859131, which Crowley marks as no longer available; Wholesale Marine lists 8M0105210 for Bravo Three X from s/n 0W250000.
Propeller nut	`11-862907`^28,35,38,39	—	Rear propeller nut, 81 Nm. On drives from 2003 the propeller shaft anode fits over it.
Propeller thrust hub	`805100` · `805101T`^28,35,40	—	Front 805100 (Hardin shows it replacing 805100T), rear 805101T. Fit them with the taper towards the propeller.
Anode (lower unit)	`888761Q04`^42,28,43replaces 888761Q02	Martyr `CMBRAVO3KITA`⁴¹	Aluminium anode kit for Bravo Three from 2003 (s/n 0M179452 and up), for fresh or salt water; replaces 888761Q02. Mercury-branded version: 888761K02.
Anode (lower unit)	`888760Q04`^44,45,28replaces 888760Q02	—	Magnesium anode kit for Bravo Three from 2003 (s/n 0M179452 and up), fresh water only; replaces 888760Q02. Six pieces: two flat trim tab anodes, drive shaft housing plate, propeller nut anode and two trim cylinder anodes.
Anode (lower unit)	`888761Q03`^46,47,48	—	Aluminium anode kit for Bravo Three 1995–2002 (s/n 0F345868–0M179451) and Bravo Two from 1988: trim tab anode, drive shaft housing plate and trim cylinder anodes. Mercury-branded version: 888761K01; the fresh-water magnesium version is 888760Q03.
Propeller anode	`865182A01` · `865182A02`^28,35	—	Propeller shaft anode that bolts on behind the rear propeller nut (standard on Bravo Three from 2003): aluminium 865182A01, magnesium 865182A02. Crowley marks both as no longer available on their own; the nut anode comes with the complete kits 888761Q04 and 888760Q04.
Anode (lower unit)	`76214Q5`^28,35	—	Gear housing anode kit (anodic plate) of the Bravo Three. The diagrams also show a second anodic plate, 762144, which Crowley marks as no longer available; the complete anode kits cover both positions.
Anode (lower unit)	`821630Q1`⁴⁹	—	Drive shaft housing anode, Bravo Three from s/n 0W250000. One source (Hardin’s catalogue); it also comes with the complete anode kits.
Anode (lower unit)	`806190Q1`^50,51,52,53	—	Trim cylinder anode, one per cylinder, so two per drive; Bravo One, Two, Three, X, XR, XZ, Blackhawk and Vazer. Also sold as 806190T1.
Control unit	`42600A09`^54,55,56,57replaces 42600A3	—	MerCathode controller: the electronic (impressed-current) corrosion protection that comes standard with Bravo drives. Hardin’s Bravo Three catalogue shows 42600A09 replacing 42600A3. The reference electrode on the gimbal housing, 98869A17, is no longer available (Crowley).
Trim cylinder	`98703A26` · `98704A26`^58,50,51	—	Port 98703A26, starboard 98704A26, for Bravo drives from s/n 0B664190 (1988–2008 in the Quicksilver chart). SeaCore versions: 866465A02 (port) and 866464A02 (starboard).
Trim cylinder seal kit	`87399A2`^58,50,51	—	Trim cylinder overhaul kit for Bravo and Bravo SeaCore cylinders, one per cylinder.
Trim cylinder seal kit	`25-87400A2`^58,50,59	—	Trim cylinder O-ring kit for R, MR, Alpha One, Gen II and Bravo cylinders, one per cylinder.
U-joint	`864244A2`^49,60	—	Universal joint (U-joint) assembly of the Bravo Three drive. The cross and bearing kit is 865496A02 (replaces 865496A01), two per joint (Hardin).
Drain plug	`22-8M0058389`^28,26,35replaces 22-67892A06	—	Magnetic drain/fill plug kit for the gear housing and drive shaft housing; sealing washer 26-830749.
Gear oil	`92-858064K01`^61,62,63replaces 92-802854A1	—	Mercury High Performance Gear Lubricant for the drive and the gear lube monitor; number as printed in the 2018 and 2019 manuals (2002 manual: 92-802854A1).
U-joint & coupler grease	`8M0071842`^61,62	—	Mercury Extreme Grease for the gimbal bearing grease fitting, the drive shaft splines and U-joint O-rings and the engine coupler; the 2019 manual also lists it for the propeller shafts.
Propeller shaft grease	`92-802859A1`⁶¹	—	2-4-C with PTFE for the propeller shafts; the 2018 manual also allows Special Lubricant 101 (802859Q1) or Anti-Corrosion Grease (8M0071838).
Power tilt fluid	`92-858074K01`^62,63	—	Mercury Power Trim and Steering Fluid for the power trim pump and power steering; SAE 10W-30 engine oil is the approved alternative for the trim.
Flushing attachment	`91-44357Q2`⁶²	—	Flushing attachment (earmuffs) for drives with side water pickups. Drives with dual water pickups also need seal kit 91-881150K1 to block the front inlets, otherwise the engine draws air while flushing.
Raw water pump impeller	`47-59362T1`^64,65	—	Not a drive part: the impeller sits in the belt-driven seawater pump on the engine, so the right number depends on the engine. This one is for Bravo One, Two and Three packages from s/n 0B664190 whose engine has the plastic one- or two-piece pump body (engines without the block drain feature); repair kits 47-59362A4 (two-piece body) and 47-59362T6 (one-piece body). One source for the fit (the Quicksilver application chart); check the pump on your engine before ordering.
Raw water pump impeller	`47-862232A2`⁶⁴	—	Not a drive part either, and it depends on the engine: for engines with the brass seawater pump and the block drain feature (s/n 0M100001 and up). One source (the Quicksilver application chart).

Numbers checked against the sources below on 13 October 2026. Always confirm against your serial number and exact type before ordering.

Service intervals

Task	Interval
Oil level check	Daily before starting, engine cold, at the gear lube monitor (1998 manual: weekly)^62,66
Gear oil change	Every 100 h or yearly, first time after 20 h⁶¹
Anode	Inspect weekly; replace at 50 % erosion⁶¹
Corrosion protection	MerCathode: have the output and the continuity circuit tested by a dealer every 100 h or yearly. Corrosion Guard: in salt, brackish or polluted water spray the engine and drive every 2 months or 50 h (2018 manual; 2019 manual: yearly)^62,61
Propeller	Every 2 months or 50 h (fresh water only: every 4 months) take both propellers off, grease the shafts and re-torque the nuts (2019 MPI manual: yearly or every 100 h); check the nut torque every 20 h^61,62
Bellows & U-joints	Inspect U-joints, splines, bellows and clamps every 200 h or 3 years (2010 and 2018 manuals); every 300 h or 3 years in the 8.2L (2018) and 4.5L/6.2L (2019) manuals^61,67,63,62
Engine alignment	Check engine alignment every 200 h or 3 years (2010 and 2018 manuals); every 300 h or 3 years in the 8.2L (2018) and 4.5L/6.2L (2019) manuals^61,67,63,62
Gimbal bearing	A greaseable bearing gets 8–10 pumps of grease every 200 h or 3 years (2010 and 2018 manuals); the 4.5L/6.2L manual (2019) has it checked for roughness every 300 h or 3 years^67,61,62
Re-torque gimbal ring	Every 100 h or yearly⁶¹
Engine coupler splines	Grease every 200 h or 3 years (2018 manual; 2019 manual: yearly or every 100 h), every 50 h if the boat idles for long periods^61,62
Full service	Every 300 h with Mercury’s 300-hour kit for your drive’s serial range: drive gaskets, anodes, drain seals, transom (bellows) kit, shift cable and fill/drain screws^3,4
Cooling system	Flush after every use in salt, brackish or polluted water⁶¹

From Mercury’s operation manuals for MerCruiser engines with Bravo drives: carbureted Alpha/Bravo models (2018), 4.5L/6.2L MPI (2019), 8.2L MAG (2018) and 496 MAG (2010); hours or time, whichever comes first. Where the manuals differ, each value is given with its manual year, the 1998 Bravo manual in brackets. The 300-hour line follows the name of Mercury’s maintenance kit as dealers sell it, not a manual. The gimbal ring re-torque (every 100 h or yearly) is listed under tightening torques.

Specifications

Drive	Sterndrive with two counter-rotating propellers on concentric shafts: the front and rear propeller turn in opposite directions^68,57
Models	Bravo Three, Bravo Three X and Bravo Three XR, in petrol and diesel versions. In Mercury’s own documents they differ only in the ratios offered (see gear ratio). Every further X/XR difference rests on one dealer’s text, which calls the XR the heavy-duty version for high-torque big-block petrol and marine diesel engines, with a billet bearing carrier and 1-1/4 in propeller shafts^69,70
Versions	Kits go by the drive serial number: 1995–2002 s/n 0F345868–0M179451, 2003–2016 s/n 0M179452–2A514802, 2017 on s/n 2A514803 and up; no kit listing covers the first drives of 1993–1994. Serial number, ratio and model number are on the plate on the drive’s port side and stamped on the drive shaft housing behind the back cover; the transom serial is on the transom assembly decal and stamped on the gimbal housing^3,62
Years built	1993 to today; Bravo Three, Three X and Three XR are still in Mercury’s range^71,57
Gear ratio	Bravo Three and Three X: 1.36 / 1.50 / 1.65 / 1.81 / 2.00 / 2.20 / 2.43:1 (petrol and diesel versions). Bravo Three XR: 1.65 / 1.81 / 2.00:1. The ratio is on the plate on the drive’s port side^69,62
Gear oil capacity	About 2972 ml (100.5 US fl oz) including the gear lube monitor in the 496 MAG (2010), carbureted engines (2018) and 4.5L/6.2L (2019) manuals; the 2019 manual gives 2736 ml (92.5 US fl oz) for drives with dual water pickups. The 8.2L manual (2018) gives 3445 ml (dual pickups: 3209 ml), the Alpha/Bravo manual of 2002 2839 ml (96 US fl oz). Fill until the oil comes out of the vent hole without air; the figures only tell you how much oil to buy^{62,61,67,63,72}
Gear oil grade	Mercury/Quicksilver High Performance Gear Lubricant^61,62
Tightening torques	Propeller nuts: front 136 Nm (100 lb-ft), rear 81 Nm (60 lb-ft), check every 20 h. Gimbal ring clamping screws (gimbal ring to steering shaft): 68–74 Nm (50–55 lb-ft, 1998 manual), re-torque every 100 h or yearly^62,66,61
Propeller	Two propellers, front and rear, turning in opposite directions; up to 16 in diameter⁶⁸
Cooling	No water pump in the drive. Water enters through the gear housing pickups (side pickups, or dual pickups with extra inlets at the front) and is drawn by a belt-driven seawater pump on the engine: plastic one- or two-piece body on earlier engines, brass pump on engines with the block drain feature (s/n 0M100001 and up)^64,62

Good to know

Read the serial number on the drive’s port side before ordering anything. The 300-hour and anode kits change at 0M179452 (2003 drives) and the 300-hour kit again at 2A514803 (2017 drives); transom kit 8M0095485 is listed only up to 2A514802, so ask a dealer for newer drives.^62,3,1,7
There is no impeller in a Bravo leg. If the engine runs hot, check the belt-driven seawater pump on the engine and look for blocked or fouled water pickups on the gear housing; plastic-body and brass pumps take different impellers.⁶⁴
Check the gear lube monitor every morning with the engine cold. Water at the bottom or milky oil means a seal is leaking. A new or freshly filled drive can take up to about 470 ml in its first 20 hours while trapped air works out; after that, top-ups of more than about 60 ml point to a leak.⁶²
Two props, two nuts: on later drives take the propshaft anode off first, then the rear nut and rear prop, then the front nut and front prop. On refit grease both shafts, torque the front nut to 136 Nm and the rear to 81 Nm, and check both again after 20 hours.⁶²
With stainless props Mercury asks for extra anodes or a working MerCathode, so have its output tested once a year. Never paint anodes, their mounting faces or the MerCathode electrode, and use no copper- or tin-based antifouling on the drive or transom assembly; on a hull with copper antifouling leave about 40 mm unpainted around the drive, anodes and MerCathode.^63,61
New bellows mean pulling the drive, so change the U-joint, exhaust and shift cable bellows, gimbal bearing, water hose and drive gaskets in one go; on drives up to 2016 transom kit 8M0095485 has them all. Have the engine alignment checked on reassembly, and lay the boat up with the drive fully down so the U-joint bellows does not take a set and split.^10,61

On the marketplace

Browse the category on boatparts.app

Looking for a part for the MerCruiser Bravo Three? Post a wanted ad in the app — it is free, it sits on the live map, and boaters nearby who have the part aboard can answer.

Got spares you no longer need? List them in a minute. No commission, ever.

Get the app

Sources

MerCruiser is a trademark of its owner; boatparts.app is not affiliated with it. Part numbers are quoted for identification only. Spotted an error? Write to mail@boatparts.app.