Changing Your Bravo Gear Lube
These instructions should only be used as a supplemental guide
to the factory Service Manuals.
You will need:
Large Slotted Screwdriver Oil Drain Pan 3 to 4 Quarts of the proper Drive LubeThe Bravo uses Mercruiser High Performance Gear Lube.
A Drive Lube Pump (part 91-802891K2) New Drain Plug Gaskets (part 12-19183--3) Clean RagsThe lube is easier and faster to drain if it's warmed up.
If possible, run the engine on the hose until the drive warms up a little.
Lower the drive into the down position.
Bravo One and Bravo II, remove the propeller. Bravo III has the drain plug up on the nose cone.
Place an oil drain pan under the drive.
Use your large slotted screw driver and remove the lower plug (see image below).
TIP: If the drain plug is stuck, try using an Impact Screwdriver and hammer.
You will notice that oil will drain very slowly.
Use your large slotted screwdriver and remove the side vent plug from the side of the upper driveshaft housing. (see image below).
Once the Vent Screw is removed the oil will drain much faster.
Let the lube drain out for a good 15 to 20 minutes.
While the lube is draining, take note of how it looks and smells.
There should be NO evidence of water in the lube. Water will show up as white streaks in the lube. Any water at all is not acceptable and if you have water immediate action must be taken to save the drive. Water will rust the bearings, races, gears and shafts and it will ruin the drive in just a short time. If you have found water in the lube, or if you suspect the drives seals are leaking, you should pressure test the drive while it is empty. Never pressure test a drive while it's full of oil. If the drive lube has a blackish appearance, it has been much too long since last changed. If the drive lube has a gray muddy look, you have an internal failure and the drive must be serviced before put back into operation.
Just changing the lube will not fix a drive!
The Bravo One holds about 3 quarts of Mercruiser High Performance Gear Lube. More if you have a remote Drive Lube Reservoir.
We like to get 5 quarts of Mercruiser Premium Gear Lube and we use part of the first quart to flush through the drive to clean out some of the older lube.
If you have an internal Remote Gearlube Reservoir, remove it from it's bracket and pour it out. Look in the bottle and if you see muddy goo or an oily slime, remove the reservoir and clean it out in a parts washer making sure it's clean and dry when complete.
When the lube is done draining, take some time and inspect the drain and vent holes for the old gaskets. A pick works well to pick the old gaskets out of the holes. Be aware that older gaskets get rock hard and they are more difficult to remove. Make sure the gaskets aren't stuck on the drain plugs. Locate your new gaskets and place them on the screws and set them aside.
Drives are filled from the bottom up.
This is made easy with the use of a Gear Lube Pump.
The Gear Lube Pump fits into the standard quart-size gear lube bottle.
Thread the end of the pumps tube into the lower gear housing drain hole and pump the lube into the drive. Keep pumping until lube flows out the top vent hole in the upper driveshaft housing.
Before removing the pumps hose, go ahead and install the top plug making sure the new gasket is in place. This will help hold the lube in the drive while you are trying to get the lower plug installed. Remove the pumps fill hose and install the lower plug making sure the new gasket is in place.
Re-tighten both screws with your large slotted screwdriver.
Wipe up the mess and discard the pan of old lube properly.
If you have a Remote Drivelube Reservoir, fill it up to the "FULL" line. Keep a little spare lube in the boat. The first time you run the boat some air might "burp" out of the drive and the reservoir bottles fluid level might drop a little. Some bottles have an alarm float which can sound your dash buzzer alarm should the fluid level drop too much.
Safety
Lubes, greases and oils can be bad for your health. Wear rubber gloves. Always wear safety glasses. Be smart.