How To Service A Bravo 1 Outdrive

Mercruiser Bravo Sterndrive Service and Maintenance

All of the boats I accept owned since 2003 have had Mercruiser Bravo Three sterndrives. I try to do my best to maintain them, and before creating this page I couldn't ever retrieve all of the private maintenance steps that needed to be done. Occassionally, I ended up making repairs that could accept been prevented by recommended maintenance. So finally I decided to put this data on my website, where I could easily reference information technology from anywhere. I could also share it with anyone else who might find it useful, and invite comments to maybe fine tune the steps or add new steps that I hadn't thought well-nigh. This should give us all a great reference for what needs to exist washed to keep our sterndrives in smashing shape.

I started out by obtaining the Mercruiser Bravo Service Manual, too chosen Service Transmission #28. The copy I used to develop this page was dated June 2003. I don't really look anything covered here has changed, but if anyone can provide a newer service manual, or advise me of whatever changes, I would definitely welcome that. Too, since this manual covers all Bravo sterndrives, everything presented here also pertains to Bravo I and Bravo II sterndrives. This is all just routine maintenance, nothing that would be involved plenty that the internal differences of these drives would come into play.

The sections of Service Manual #28 that I referred to are listed below, and each is linked to a PDF file of that department in case y'all would similar to download it and review it:

Tabular array of Contents / Notice to Users
Section 1B - Maintenance
Section 2A - Removal, Installation and Adjustment
Section 4A - Transom Associates Service Procedures Requiring Minor Disassembly
Section 7A - Corrosion Protection

I'1000 not going to interruption the steps down into winterizing (layup) / de-winterizing (recommissioning) like they exercise in the service transmission, but instead I'thou going to list everything in the order I would practise it, since I generally practise all of this in the spring. It'southward too cold when I put the boat away for the winter to mess with this stuff. This first section deals with stuff that needs to exist done from the inside of the gunkhole. It tin can be washed with the sterndrive on or off of the boat, simply I think information technology's better to take the drive drained of gear oil and removed from the boat offset. If nothing else, at least begin draining the gear oil before starting the steps inside the boat so that it volition hopefully be done draining by the fourth dimension you're ready for the steps exterior of the boat. I know the stuff inside the gunkhole isn't servicing the sterndrive itself, merely it is servicing components that directly collaborate with the sterndrive, and then I'm including them.

In order to keep this page from being incredibly long, I've shrunk each step downward to brandish just the title. Click on it to show the details of that step. With all of the steps contracted, information technology's easy to take a look at the materials and tools needed, so that if you were planning to do all of these steps in one trip to the boat, yous would be able to gather up everything you needed to bring with you.

Almost all of these steps are easier or more fun with someone to help, so attempt to recruit a friend for aid doing this stuff!

From inside the boat:

Lubricate the Shift Cable (Click to aggrandize)

Frequency: Annually
Materials needed: SAE 30W Engine Oil
Tools needed: None

Lubricate the pin points and the guide contact surfaces with SAE 30W Engine Oil. The moving-picture show below shows the 3 pivot points (a) and the 2 guide contact surfaces (b). I pour the oil into the cap from the oil can, and carefully pour a little scrap onto all of the areas shown below, keeping a rag handy to wipe up whatever spillage. Using some kind of dropper or something might exist a less messy method, so permit me know if you have whatsoever suggestions. This is an of import step to keep your boat shifting smoothly and prolonging the life of your shift cables! (Reference: Section 1B, Page 10)

Lubricate the Steering Arrangement (Click to expand)

Frequency: Every 100 hours or Annually
Materials needed: SAE 30W Engine Oil, Special Lubricant 101 (92-802865A1)
Tools needed: Grease Gun

These three steps are done behind the engine, near the transom. This outset step only applies if your steering cable has a grease fitting. Plough the steering cycle until the steering cable is fully retracted into the cable housing. Apply approximately 3 pumps of Special Lubricant 101 to the grease fitting. The picture show below shows the location of the grease fitting (a). My trouble hither is that I have just ever been able to detect Special Lubricant 101 in a tube, not in a grease gun cartridge. I'one thousand pretty sure I read that 2-4-C with Teflon is the suitable replacement for Special Lubricant 101, and it is available in a cartridge. If anyone can confirm this for me with a reference, that would be neat. In the meantime I use 2-4-C for this despite the manual calling for Special Lubricant 101. (Reference: Department 1B, Page 22)
Turn the steering wheel until the steering cable is fully extended from the cable housing. Lightly lubricate the exposed function of the cablevision with Special Lubricant 101. The picture below shows the extended steering cable (a). I squeeze Special Lubricant 101 on the cable and smear it effectually with my fingers. (Reference: Section 1B, Page 22)
Lubricate the steering arrangement pivot points with SAE 30W Engine Oil The picture below shows the pin points where the steering arm connects to the steering cable (a). (Reference: Section 1B, Page 23)
This final stride just applies to twin engine boats. Lubricate the tie bar pivot points with SAE 30W Engine Oil. I don't take a motion picture of this, merely basically it's but the same matter on the steering arm of the other drive. (Reference: Section 1B, Page 23)

Lubricate the Engine Coupler (Click to expand)

Frequency: Every 100 hours or Annually
Materials needed: Engine Coupler Spline Grease (92-802869A1)
Tools needed: Grease Gun

Lubricate the engine coupler splines through the grease fitting(s) on the coupler by applying approximately 8-10 pumps of Engine Coupler Spline Grease to the grease plumbing fixtures(s). The moving-picture show below shows the grease fittings (a) on steel couplers (left) and aluminum couplers (right). Even though this procedure is recommended every 100 hours, replacing a worn out coupler is enough of a pain that greasing it every 50 hours or and then isn't a bad idea. Note that this process actually makes the near sense when the sterndrive is attached to the boat, so you lot may want to leave this for the very last step. (Reference: Section 1B, Folio 24)

Make clean the Gear Lube Monitor (Click to expand)

Frequency: Every 2 Years
Materials needed: Rag and/or solvent, or parts washer
Tools needed: Pliers

If you've drained the gear oil from the outdrive, now'due south a good time to accept a wait inside the gear lube monitor for any sludge. If you haven't drained the gear oil, well, and so try again next year. If there is some sludge in there, I like to remove the reservoir past unhooking the rubber strap that holds information technology in, disconnecting the two bullet connectors that become to the alarm, and removing the plastic clamp that holds the hose on. The pliers might come up in handy hither, as they will when it's time to reconnect the hose. I so use the parts washer to run some solvent in the reservoir, slosh it effectually, and empty it, until information technology looks pretty make clean. You lot could also use a rag and some spray solvent to become the worst out of there, but be careful not to use a solvent strong enough to damage the plastic. Also rinse it with water afterwards and let to dry completely or dry it off with compressed air. The moving-picture show below shows the gear lube monitor (a). (Reference: Personal experience)

From outside the gunkhole:

Remove the Sterndrive (Click to expand)

Frequency: Every 200 Hours or Annually
Materials needed: None
Tools needed: 5/viii" socket, swivel, extension, and 3/viii" ratchet; 5/eight" combination wrench

Disconnect the speedometer cable from the sterndrive. You may or may not accept to do this if your speedometer is driven by a pitot or paddle wheel attached to the transom, or if you have 2 drives and the speedometer is connected to the other one. But yous should definitely bank check before ignoring this footstep then that yous don't end upwards having to supplant some broken pieces. Yous will probably have to put the drive up at least part way, the higher the better. So achieve around to the side of the bulldoze closest to the transom, plough the hose plumbing equipment nigh a quarter plough counter-clockwise, and pull the hose out. The picture below shows this process. (Reference: Section 2A, Page half-dozen)
Disconnect the trim cylinders from the sterndrive. To exercise this, put the drive down until the cavitation plate is level with the ground. This should be almost all the way downwards if non all the way. If you lot're using a drive cart, put the cart nether the drive now, but don't tighten it upwards just yet. Remove the terminate caps (a) by turning them counter-clockwise, which y'all should exist able to do with your hand. Next, hold the nut (b) on ane side of the bulldoze with the combination wrench, and unscrew the other nut (b) with the socket and ratchet. When one of the nuts comes off, remove the flat washer (c) and bushing (d) from that side. Then pull the ballast pin (the threaded rod the nut screws on to) out by putting the combination wrench on the remaining nut and spinning information technology both ways while pulling it away from the drive. Shaking the drive up and down a flake should help information technology come out more easily. Remember that when the ballast pin is out, zero will be belongings the bulldoze up anymore, so it volition want to fall against the transom. This is OK, just be sure to hold it and let it down gently instead of slamming against the boat. If you are using a drive cart to hold the drive, it will prevent the drive from dropping. One time the anchor pin is out, yous should tighten up the drive cart.(Reference: Section 2A, Folio 6)
Remove the locknuts that hold the sterndrive to the bell housing. Do this by using the socket, swivel, extension and ratchet to remove all 6 locknuts, (a) in the motion-picture show below. There will be five flat washers, remove those as well. The eye nut on the port side will have a ground plate (b) under information technology instead of a flat washer. The ground plate does not get removed.(Reference: Department 2A, Page vii)
Remove the sterndrive from the boat. If you're using a drive cart, get ahead and tighten information technology upward at present. If non, take a potent friend handy for this part. Make sure the shift lever on your boat is in neutral. Pull the sterndrive abroad from the gunkhole, but don't permit it get more than nearly two inches from the bell housing. Reach between the drive and the bell housing and make sure the shift cable linkage jaws (a) open up up and release the shift cable end (b). At present pull the drive consummate away from the boat. (Reference: Section 2A, Page vii)

Check the Gimbal Begetting and Bellows (Click to expand)

Frequency: Every 200 Hours or Annually
Materials needed: None
Tools needed: None

Using your fingers, reach inside the bong housing and rotate the gimbal bearing (a). It should rotate effortlessly with no rough spots. Also push and pull on it to make sure it does not motion in any direction, other than to rotate. If you feel any movement, or any roughness in the rotation, take the begetting replaced by a professional person. Also note the condition of the bellows (b). The bellows should exist flexible, non rigid, and have no tears or cracks. If the bellows are in bad shape, or there is any water in in that location at all (grease is OK), accept them replaced past a professional. (Reference: Section 4A, Folio 27)

Grease the Gimbal Bearing (Click to aggrandize)

Frequency: Every 200 Hours or Annually
Materials needed: U-Joint and Gimbal Bearing Grease (92-802870A1)
Tools needed: Grease Gun

Lubricate the gimbal bearing through the grease fitting on the transom assembly by applying approximately 8-10 pumps of U-Joint and Gimbal Bearing Grease to the grease fitting (a). (Reference: Section 1B, Page 23)

Cheque Engine Alignment (Click to aggrandize)

Frequency: Every 200 Hours or Annually
Materials needed: None
Tools needed: Engine Alignment Tool (91-805475A1)

Attempt to insert the solid end of the alignment tool (a) through the gimbal begetting (b) and into the engine coupler (c) splines. It should slide in easily with no force required (slides in and out freely with two fingers), and bottom out in the coupler. If the tool does not easily slide all the way in and out, the engine alignment is off. Have a professional suit the engine alignment. (Reference: Department 1B, Page 27; Engine Specific Service Manual)

Torque Steering Basics (Click to expand)

Frequency: Every 100 Hours
Materials needed: None
Tools needed: Torque wrench, 9/16" socket (standard gimbal rings) or 5/8" socket (magnum gimbal rings)

Torque the 2 nuts (a) at the top of the transom associates to 55 lb-ft. These nuts secure a U-commodities to the steering associates. If this is loose, non only exercise you loose some steering power, but very expensive harm can occur. Trust me, I've been there. (Reference: Section 2A, Page 2)

Lubricate Sterndrive and Replace O-Rings (Click to aggrandize)

Frequency: Every 100 Hours
Materials needed: Bravo Installation Kit (16755Q1), Engine Coupler Spline Grease (92-802869A1), U-Joint and Gimbal Bearing Grease (92-802870A1), 2-4-C Marine Lubricant (92-802859A1), Special Lubricant 101 (92-802865A1)
Tools needed: Rags; Wire brush; Grease gun; Needlenose pliers

Remove old O-rings and clean surfaces. The Bravo install kit comes with vi O-rings. There are iii on the shaft at the tiptop of the drive (2 thick and one thin), a thick round i around the shift cable linkage jaws, a funky shaped one around the h2o passage on the bulldoze, and a small 1 on the bell housing (the part still attached to the boat) around the gear oil check valve. Discover all of these and remove them. Effort to retrieve what went where. As you remove each one, wipe off as much of the old grease in that area as you can, and and so use a wire brush to clean up any corrosion in these areas. (Reference: Personal Experience)
Grease the U-joints with a grease gun loaded with U-Joint and Gimbal Begetting Grease. There are two grease fittings (a), and they are a little catchy to get to. Apply approximately iii-6 pumps of grease, until a small amount of grease begins to button out of the bearings (b). (Note that "heavy duty" U-joints do not have grease fittings, and then y'all cannot exercise this step.) (Reference: Section 1B, Page 26)
Grease the O-ring areas (a). Using U-Joint and Gimbal Bearing Grease, grease the circle groove around the shift linkage jaws and the funky shaped groove around the water passage. Press the new O-rings into these grooves, and smear the grease onto the exposed O-ring surfaces. (Reference: Section 2A, Page thirty)
Grease the shift linkage. Agree the shift linkage associates (a) out as far as it will go with a pair of pliers. Grease the underside of the lower lip (c) with Special Lubricant 101. The jaws need to remain open (b) in order for the shift cablevision to reconnect when you reinstall the drive. (Reference: Section 2A, Page 31)
Grease shaft splines (a) and the grooves (b) for the new O-rings with Engine Coupler Spline Grease. Don't be shy with the grease, you want the new O-rings to be able to slide all the way upward into their groove, and y'all want plenty of grease on the splines for when it engages with the engine coupler. Slide the new O-rings onto the shaft one at a time, until they are all in identify. Two identical O-rings slide all the manner up to the top of the shaft (b), while the third goes correct behind the splines (a). (Reference: Section 1B, Page 26)
Install the gear oil check valve O-band. Press the new O-band into place around the gear oil check valve (a). There is probably a little scrap of gear oil in the groove that will hold the O-ring in place. (Reference: Personal Experience)
Grease bong housing studs. Using the wire brush, make clean off any corrosion around the studs, and make clean whatsoever dirt out of the threads. Rub a low-cal coat of 2-4-C Marine Lubricant on the exposed surface area of the bong housing studs (a). This will aid the nuts keep and off without difficulty, and help prevent corrosion. (Reference: Section 2A, Page 2)

Install The Sterndrive (Click to aggrandize)

Frequency: Every 100 Hours
Materials needed: 2-four-C Marine Lubricant (92-802859A1)
Tools needed: 5/8" socket, swivel, extension, and ratchet; 5/viii" combination wrench; Torque wrench

Install the sterndrive. Brand sure the shift lever on your boat is in neutral. Lift the trim cylinders so that they stick stright out from the boat. With one hand, hold the shaft and guide it into the gimbal bearing. As y'all slide the sterndrive on, make sure the shift cable (b) engages with the shift linkage jaws (a). Make sure the trim cylinders stay on height of the cavitation plate every bit y'all slide the drive on! If they autumn down you will have to pull the bulldoze back off. Every bit yous become the drive almost all of the manner on, you lot may have to rotate the propeller in order to get the shaft splines to align with the coupler. In one case the sterndrive is in identify, spin the prop to make certain the drive is in neutral. If the prop doesn't spin, the shift cable didn't appoint the shift linkage jaws, so yous need to pull the drive back off and attempt again. In one case the drive is firmly in identify, put the 5 washers and six nuts dorsum on the bell housing studs. Remember that the center stud on the left side has a grounding plate (c) and doesn't get a washer. Starting with the center ii, torque the 6 nuts (d) to 50 lb-ft. (Reference: Section 2A, Page 29-32)
Install trim-in limit insert. In that location is a white nylon piece call the "trim-in limit insert" in the hole that yous removed the ballast pin from. It may take moved effectually, so you lot need to bank check its position before reattaching the trim cylinders. On Bravo Ane and Bravo Two drives, the insert (a) goes frontward, toward the transom. On Bravo Threes, it goes aft, abroad from the boat. (Reference: Section 2A, Page 33)
Grease trim hardware and adhere trim cylinders. Take the 4 black rubber bushings (b) and apply a liberal amount of ii-4-C Marine Lubricant to them, and insert them into the trim cylinder pivot ends (a) with the smaller diameter going within the pivot ends. Apply a liberal amount of 2-4-C Marine Lubricant to the anchor pin, including the threads. Line up the trim cylinders with the hole that contains the trim-in limit insert, and begin inserting the ballast pivot through one of the pivot ends. Apply a blanket of 2-4-C Marine Lubricant to the 2 flat washers with the big holes. Place one washer between the bushing and the trim-in limit insert, and push the ballast pin through the washer and into the hole. Every bit it emerges from the other side, identify the other washer on that side. Eye the anchor pin. Apply a coating of 2-four-C Marine Lubricant to the remaining 2 washers (c) and the two nuts (d). Identify a washer and nut on each side of the anchor pin. Holding one nut with the 5/eight" combination wrench, utilise the ratchet and socket to tighten the other nut. The nuts volition lesser out when they reach the ends of the threads, and so tighten until they finish. In that location should be plenty of thread left exposed to attach the two trim cylinder caps (e). Thread the caps on by mitt. (Reference: Section 2A, Page 34)
Hook up the speedometer. If y'all had to disconnect the speedometer before, now is the fourth dimension to reconnect it. (Note: If your speedometer had non been working previously, the passage in the drive may be clogged up. Y'all can blow some compressed air into the passage (b) before hooking the speedometer back up to make sure it is clear of mud or debris.) Trim the drive fashion up, achieve behind it, and insert the plastic fitting (a) into the pigsty it came out of (b). The fitting merely goes in ane style, so don't force it if information technology doesn't feel right. Once it is seated, rotate the fitting almost a quarter turn clockwise then that information technology points toward the transom (c). This locks it into place. (Reference: Department 2A, Page 35)

Paint The Sterndrive (Click to expand)

Frequency: Annually
Materials needed: Mercury Light Gray Primer (92-802878 52), Mercury Phantom Black Spray Paint (92-802878Q 1), Mercury Corrosion Baby-sit (92-802878-55)
Tools needed: Wire castor

Paint the sterndrive. I won't become into a lot of detail hither, because the procedure could be very different depending on the condition of your drive. Assuming information technology is in good shape, with minimal corrosion, here is the minimum you should do. Take the wire brush and remove any corrosion you observe, until bare metal is exposed. This usually happens get-go near the props and where the trim hoses connect to the trim cylinders. Anywhere that the paint has been scraped away may have some corrosion too. When this is all cleaned up, spray Mercury Light Gray Primer on all blank metal (just not the props). (Note: If you exercise not plan on replacing your anodes, be sure not to go any paint on them.) Then spray Mercury Phantom Black Spray Paint over the primer until the drive looks every bit good as you desire it to. Follow the directions on the cans for temperature requirements and the corporeality of time required between coats. Apply every bit many coats equally needed to become the drive looking expert. Finally, spray Mercury Corrosion Baby-sit on the entire drive to aid prevent corrosion and keep the drive shiny. Again, read the directions on the tin. (Reference: Section 1B, Page 8)

Grease The Propshaft (Click to expand)

Frequency: Every ii-four months
Materials needed: 2-4-C Marine Lubricant (92-802859A1)
Tools needed: Wire brush

Grease the propshaft. Remove the propeller(s), paying conscientious attention to how the nuts, washers, and spacers were installed. Apply a liberal amount of 2-iv-C Marine Lubricant to the entire propshaft(s). (Note: if yous have a Bravo I, do not reinstall the prop at this time, since information technology needs to be removed in order to change the gear oil in the side by side step.) Reinstall the propeller(southward), replacing the hardware in the same order information technology was removed, and securely tighten the nut. Lots of people skip this procedure and don't perform it unless they have a real demand to remove the prop, but as you lot tin see above, this process is recommended every 2 to 4 months. Keeping upwards with this keeps your propshaft free of corrosion, making the prop(s) easy to remove when you accept to, and also makes sure that the prop(s) are securely attached to the shaft and won't pop off when y'all least await it. Either of these things could be really expensive and are hands preventable. (Reference: Department 1B, Page 24)

Change The Gear Oil (Click to aggrandize)

Frequency: Every 100 Hours or Annually
Materials needed: Mercury High Performance Gear Lube (92-802854A1)
Tools needed: Large flat-head screwdriver, Gear Oil Pump

Drain the gear oil. If you have a Bravo One, make sure the drive is trimmed all the mode down, otherwise trim the drive all the mode up. With the screwdriver, remove oil fill/bleed screw (a). On Bravo Ones, this is on the aft end of the bulldoze, below the prop. On Bravo Two and Iii drives, the screw is most the bottom of the bulldoze at the frontward end. At that place is a washer (b) along with the screw. Sometimes it stays attached to the screw, and other times it stays in the hole. Keep runway of it, you must reinstall information technology along with the spiral or water volition get into your bulldoze. The top of the screw is a magnet. Inspect it for any metal. If at that place is a lot of metal stuck to the magnet, you may have an internal problem that needs to be checked by a professional. As the oil begins to drain, lookout for water or milkiness in the oil. If you see any, have a professional test your drive for leaks and repair it. There is a vent screw and washer at the top of the bulldoze. Remove this so that the oil drains faster. (Reference: Department 1B, Page 21)
Fill the gear oil. Once the gear oil is completely drained, make sure the drive is raised or lowered then that the propeller shaft is level. Claw up the pump to the oil make full drain pigsty, and pump until an air-free stream of oil flows from the oil vent hole at the tiptop of the drive. At that point, install the washer and spiral in the oil vent hole. Keep pumping until gear oil appears in the gear oil reservoir in the boat. Disconnect the pump and replace the washer and spiral in the oil fill/drain hole. Top off the gear oil reservoir. Later, after running the boat in gear, be sure to bank check the reservoir and peak off if necessary. Gear Oil Capacities are every bit follows:
Bravo One: 88 oz - 2.75 quarts
Bravo Two: 104 oz - 3.25 quarts
Bravo Three: 96 oz - 3 quarts
If you pay someone to practice this for you, and they try to charge you for 4 quarts or more, they're ripping you lot off! (Reference: Department 1B, Page 3, 20-21)

Replace The Anodes (Click to expand)

Frequency: When existing anodes are corroded to 50% of their original material.
Tools needed: 5/16" socket, vii/xvi" socket, swivel, extension, and 1/4" ratchet; 3/8" allen wrench